Following the success of previous years, this session will explore reasons for the under-representation of different groups (gender identities, sexual orientations, racial and cultural backgrounds, abilities, religions, nationality or geography, socioeconomic status, ages, career stages, etc.) by welcoming debate among scientists, decision-makers and policy analysts in the geosciences.

The session will focus on both obstacles that contribute to under-representation and on best practices and innovative ideas to remove those obstacles. Contributions are solicited on the following topics:

- Role models to inspire and further motivate others (life experience and/or their contributions to promote equality)
- Imbalanced representation, preferably supported by data, for awards, medals, grants, high-level positions, invited talks and papers
- Perceived and real barriers to inclusion (personally, institutionally, culturally)
- Recommendations for new and innovative strategies to identify and overcome barriers
- Gender Equality Plans (GEP) in European host institutions: the good, the bad, and the ugly
- Best practices and strategies to move beyond barriers, including:
• successful mentoring programmes;
• networks that work;
• specific funding schemes;
• examples of host institutions initiatives;

Report on situations that you may have experienced in light of recent socio-political changes.

This session is co-organised with the support of the European Research Council (ERC).

Sitting under a tree, you feel the spark of an idea, and suddenly everything falls into place. The following days and tests confirm: you have made a magnificent discovery — so the classical story of scientific genius goes…

But science as a human activity is error-prone, and might be more adequately described as "trial and error", or as a process of successful "tinkering" (Knorr, 1979). Thus we want to turn the story around, and ask you to share 1) those ideas that seemed magnificent but turned out not to be, and 2) the errors, bugs, and mistakes in your work that made the scientific road bumpy. What ideas were torn down or did not work, and what concepts survived in the ashes or were robust despite errors? We explicitly solicit Blunders, Unexpected Glitches, and Surprises (BUGS) from modeling and field or lab experiments and from all disciplines of the Geosciences.

Handling mistakes and setbacks is a key skill of scientists. Yet, we publish only those parts of our research that did work. That is also because a study may have better chances to be accepted for publication in the scientific literature if it confirms an accepted theory or if it reaches a positive result (publication bias). Conversely, the cases that fail in their test of a new method or idea often end up in a drawer (which is why publication bias is also sometimes called the "file drawer effect"). This is potentially a waste of time and resources within our community as other scientists may set about testing the same idea or model setup without being aware of previous failed attempts.

In the spirit of open science, we want to bring the BUGS out of the drawers and into the spotlight. In a friendly atmosphere, we will learn from each others' mistakes, understand the impact of errors and abandoned paths onto our work, and generate new insights for our science or scientific practice.

Here are some ideas for contributions that we would love to see:
- Ideas that sounded good at first, but turned out to not work.
- Results that presented themselves as great in the first place but turned out to be caused by a bug or measurement error.
- Errors and slip-ups that resulted in insights.
- Failed experiments and negative results.
- Obstacles and dead ends you found and would like to warn others about.

--
Knorr, Karin D. “Tinkering toward Success: Prelude to a Theory of Scientific Practice.” Theory and Society 8, no. 3 (1979): 347–76.

Join us for an interdisciplinary session, where we will explore how cutting-edge omics technologies are transforming our understanding of ecosystems and their resilience in response to climatic change across all scales. Over billions of years, spatial and temporal shifts in environmental conditions have driven the evolution of diverse microbial, fungal, plant and animal species, shaping the ecosystems, atmosphere, and climate of Earth. Gaining insights into how these organisms and biomes function, adapt, and interact requires a deep understanding of their components and the complex feedback systems they form.

Technological innovations in measuring and interpreting “meta-omics” datasets are now providing unprecedented mechanistic insights across diverse organisms, scales, and environmental spheres. These advances also drive the development of next-generation models to predict ecosystem function. In this session, we bring together ecologists, geochemists, and evolutionary biologists to examine the available omics toolkits for studying organisms and communities and to discuss ongoing efforts to integrate this knowledge across biological and temporal scales to address pressing Earth system science questions.

By combining eco-evolutionary insights with ecosystem-level concepts like community traits and resilience, we aim to foster future ITS sessions that apply integrated omics approaches alongside geoscience techniques for a deeper, mechanistic understanding of ecosystems.

We welcome contributions studying all Earth’s spheres (Biosphere, Atmosphere, Hydrosphere, Cryosphere, Geosphere), using a wide range of omics datasets (metagenomics, metatranscriptomics, metabolomics, proteomics, lipidomics, spectranomics, ionomics, elementomics, and isotopomics) as well as other large datasets such as trait, phenotype, inventory, pollen, and fossil records. We are particularly interested in studies involving control experiments, long-term ecological surveys, or flux networks, as well as research that provides mechanistic insights and employs big data in Earth system models or machine learning to scale patterns across space and time.

Advances in forest system modelling and monitoring techniques are crucial for deepening our understanding of forest ecosystems and their dynamic responses to environmental stresses and disturbances. These advancements are instrumental in addressing global environmental challenges by improving predictions and adapting management strategies accordingly. This session aims to bring together scientists and researchers focused on the latest advancements in forest systems modelling, observational techniques, and analytical methodologies to enhance our understanding of forest structural dynamics, soil carbon (C) dynamics, and the impacts of natural disturbances such as wildfires, insect’s outbreaks, pathogens/disease, droughts, and windstorms. Specifically, this session covers the following topics:

• Advancements in Forest System Modelling: Presentations on new models or significant improvements in existing models, that help predict and analyse forest growth, structural dynamics, C sequestration in biomass and soils, and ecosystem resilience. This includes models that integrate hydrological, meteorological, and biological processes.

• Innovative Monitoring Techniques: Studies showcasing novel observational technologies or methodologies, including remote sensing, isotopic tracing, or ground-based monitoring systems that provide new insights into forest mortality, growth patterns, and C cycling.

• Impact of Natural Disturbances: Research on how wildfires, insect’s outbreaks, pathogens/disease, droughts, and severe wind events alter forest structure, soil C stocks, and overall ecosystem functions. Contributions may include forward-looking information, post-disturbance recovery processes, disturbance modelling, and strategies for disturbance mitigation and adaptation.

• Cross-Scale Integration: Contributions that demonstrate the integration of innovative integrations of data and models across different spatial and temporal scales to understand forest biomass and soil dynamics comprehensively.

• Implications for future Management Strategies: Insights into how advanced modelling and monitoring approaches can shape policy development, offer a range of adaptation strategies, and inform management practices to enhance forest resilience and C retention.

Disturbances, such as extreme weather events, play a key role in shaping ecosystems. Under climate change, extreme weather hazards undergo changes in frequency, intensity and seasonality. While ecosystem-based adaptation and nature-based solutions are gaining traction, it is crucial to elucidate the diverse interactions between extreme weather risk, ecosystems, and their services.

This session seeks to highlight research on the nexus of extreme weather events and ecosystems. This includes: 1) investigations into the key attributes and patterns of extreme weather events which affect ecosystem composition, structure and functioning. 2) studies on how ecosystems respond to and recover from extreme weather events across past, present, and future climates are of interest. 3) Implications of extreme weather impacts on ecosystems for biodiversity and ecosystem service provision. We welcome a diverse array of contributions, including theoretical analyses, modeling approaches, field studies, experimental designs, and remote sensing analysis.

Key topics include:
- Ecosystem (terrestrial, coastal or marine) responses to extreme weather
- Role of extreme weather in shaping ecosystem composition, biodiversity, structure and functioning
- Vulnerability assessments of ecosystems
- Natural hazard risk to ecosystems in past, present and future climates
- Changes in ecosystems service provisions due to extreme weather events
- Resilience and recovery dynamics
- Impact and efficacy of Nature-Based Solutions (NBS) under extreme conditions, risk of maladaptation or disservices
- Regime shift / tipping points in ecosystems due to extreme weather events
- Extreme weather disturbance regimes affecting ecosystems across time
- Identification of extreme weather risk hotspots
- Interactions of natural hazard and anthropogenic disturbances to ecosystems

This session aims to (re)introduce biodiversity, an essential component of many aspects of life on Earth, as a notion that offers a wide array of multidisciplinary work from numerous fields of research, including but not limited to the geosciences and ecology. While biological diversity is vital for natural ecosystems such as forests and wetlands, and crucial for maintaining healthy freshwater ecosystems, soil systems, and oceans, it is also a factor that affects an ecosystem’s response to disturbances, in turn affecting notions such as (ecosystem) integrity, health and resilience. Biodiversity is also intrinsically linked with the Earth’s processes, geomorphology, formation, and development. The United Nation’s definition of biodiversity, or biological diversity, is: the variety of life on Earth and the natural patterns it forms. A wide range of studies on biological diversity also encompass ecological diversity and ecosystem diversity, since the diversity of ecosystems also affects the diversity of organisms that inhabit them. Earth Science recognizes the role of biotic factors in governing geophysical processes, and feedback mechanisms, across a wide range of spatial and temporal scales. Studies show that the control of biota might be part of a longer-term cycle, in which the dominance of biotic and abiotic processes not only switch, but depend on each other. Biota and abiotic processes may have co-evolved over both longer and shorter timescales. Scientific evidence from the geoscience community is therefore valuable in many political decisions for restoration, or rewilding, including the recent EU Nature Restoration Law. Also, research in these fields may contribute to policy on preparation for and/or prevention from geohazards, including those that may be triggered by anthropogenic interference and/or climate change, acting as stressors which affect diversity within a system.
Thus, in this session we aim to recognize the wide range of geoscience research projects that focus on or highlight aspects of biodiversity, while welcoming those that favor inter- and/or transdisciplinary approaches. Through these presentations, we hope to demonstrate the broad spectrum of biodiversity-related areas in which the geosciences contribute and where geoscience research gaps need to be addressed.

Recent research highlights key challenges and opportunities in citizen and community science for biodiversity research. The "science of citizen science" requires further exploration of core research questions, methodologies, and supporting technologies. Citizen science data are increasingly important for scientific studies, particularly in biodiversity and pollution research and for monitoring Sustainable Development Goals. However, improvements in data stewardship practices are needed to maximise the benefits for science and society. Frontiers for future research include sampling underrepresented taxa and regions, estimating species abundance from presence data, and understanding ecological and species interactions. Outstanding challenges involve observer behaviour, non-structured but opportunistic sampling, statistical models, and communication with the local and underrepresented communities –with potential solutions including collecting additional metadata, combining datasets, refining analytical methods, and reevaluating research goals. The session welcomes anyone involved in connecting citizen or community science with biodiversity research, at any scale—from community-driven local projects to large crowd-sourced data initiatives. We aim to highlight the scope, challenges, and potentials of citizen science contributions to biodiversity research, conservation efforts, and how these incorporate and benefit the communities directly involved.

Global change drivers on ecosystems, such as land/sea use change, direct exploitation, climate change, pollution, and invasive alien species are the major contributors to the accelerating biodiversity crisis. Mounting evidence has demonstrated the link between these drivers and changes in biodiversity, such as the loss of species, declines in functional and genetic diversity, and reduction in geodiversity. However, our understanding of the impacts of these drivers on biodiversity across local to global scales remains limited.

In this session, we warmly invite contributions related but not limited to studies on 1) the current state or patterns of biodiversity and main drivers; 2) changes in biodiversity and ecosystem functioning; 3) trends and future scenarios of biodiversity change; 4) species migrations and links to environmental and anthropogenic influences, and 5) changes in biodiversity resulting from conservation, restoration, management and policy.

We aim to bring together excellent research about past, present, and future biodiversity, using data from field sampling, and airborne or space-based remote sensing observations. We welcome studies ranging from local-scale field experiments to large-scale theoretical modeling, including both individual-ecosystem (i.e. terrestrial, marine and freshwater systems) and cross-ecosystem studies. We explicitly welcome novel conceptual ideas, large-scale observations, field experiments, earth system modeling, or data synthesis related to biodiversity change across spatial and temporal scales, and from various data sources toward a better understanding of global change impacts on biodiversity.

In the face of increasing climate change impacts, environmental stresses, limitations on natural resource, along with socio-economic pressures, safeguarding the resilience of agricultural systems is a critical policy imperative. Resilience can be defined in various ways and typically includes elements of preparedness, absorbing and recovering from shocks, adaptation as well as transformation. This session aims to address key challenges of agricultural resilience, including the need for a unified conceptual monitoring and modelling framework, to facilitate the development of coherent policies across regions, countries and sectors. More specifically, the session will provide an overview of current research (methods and knowledge), identify gaps, and propose applicable strategies for enhancing resilience evaluation. Hereby, we aim to bridge natural and socio-economic sciences by addressing links and synergies with food security and sustainability.

We welcome contributions on defining and quantifying resilience from landscape to national scales with innovative methods (e.g. multicriteria analysis, machine learning, integrated assessment modelling). We invite interdisciplinary resilience studies that integrate observational and model perspectives, and address both biophysical and socio-economic aspects.

Studies ideally assess key resilience drivers and effects ranging from climatic, environmental, economic and social factors that together sketch a comprehensive picture of the resilience of agricultural systems.

We suggest that contributions address the following questions: Which system and shocks/threats are considered and should be prioritized? Where, and on which timescale do we need to increase resilience? Which properties reinforce agricultural resilience? Over which time scale should resilience be assessed?

The global grand challenges such as climate change, air pollution and biodiversity loss are not occurring in isolation in time or space – they are closely interconnected and have potential to amplify each other, create nonlinear feedbacks and result in significant loss of ecosystem services that eventually affect societal well-being and humanity. While immediate impacts sometimes receive considerable attention, little is known about their long-term and systemic effects often resulting from cross-scale interactions. Closing these knowledge gaps requires an improved, transdisciplinary understanding of the multifaceted environmental system - a prerequisite for the development of appropriate mitigation and adaptation measures. It also requires advanced tools and concerted efforts for integration of the data originating from diverse sources.

European-scale research infrastructures and networks, e.g., ESFRI RIs like ACTRIS, AnaEE, Danubius, eLTER, ICOS, and other observation systems like WMO-GAW and ICP-IM, support the delivery of consistent, standardized data based on harmonized methodologies. The more RI networks are integrated through co-location of individual observation sites, the better understanding can be achieved on ecosystem state (e.g., terrestrial carbon storage), biogeochemical constraints (e.g., macronutrient cycles), societal drivers (e.g., land use change) and tradeoffs (e.g. biodiversity). This session will call upon presentations addressing the benefits and challenges of co-located in-situ observations, enabling researchers to address the systemic changes in a holistic manner and to advise the policymakers on cost-efficient tools for mitigation of environmental change.

This session aims to facilitate collaboration and knowledge exchange among projects, networks, and partnerships within the field of underground bioscience research. Serving as an entry point for more specialized sessions on specific aspects such as life in extreme environments, astrobiology, planetary exploration, and beyond-Earth human habitation, the session promotes a cross-disciplinary perspective. By fostering communication between initiatives, it ensures that the outcomes of diverse research efforts are widely disseminated within the EGU community, encouraging a holistic approach to advancing bioscience research in underground laboratories. The session will also explore the infrastructure requirements necessary to support future scientific developments in this unique environment.

This session, organized by the Carbon Removal Forum of Sciences in Israel, will bring together scientists, entrepreneurs, and carbon removal organizations to explore pathways for turning scientific research into real-world, scalable solutions. With a focus on carbon capture technologies from air, land, and sea, the discussion will emphasize the importance of collaboration between academia and the private sector in driving innovative, impactful carbon removal strategies.

Fire is the main terrestrial ecosystem disturbance globally and a critical Earth system process. Fire research is rapidly expanding across disciplines, highlighting the need to advance our understanding of how fire interacts with land, atmosphere and society. This need is growing as fire activity increases in many world regions. This session invites contributions that investigate the role of fire within the Earth system across any spatiotemporal scale, using statistical (including AI) and process-based models, field and laboratory observations, proxy records, remote sensing, and data-model fusion techniques. We strongly encourage abstracts on fire's interactions with: (1) weather, climate, atmospheric chemistry, and circulation, (2) land physical properties, (3) vegetation composition and structure and biogeochemical cycle, (4) cryosphere elements and processes (such as permafrost, sea ice), and (5) human health, land management, conservation, and livelihoods. Moreover, we welcome submissions that address: (6) spatiotemporal changes in fire in the past, present, and future, 7) fire products and models, and their validation, error/bias assessment and correction, as well as (8) analytical tools designed to enhance situational awareness for fire practitioners and to improve fire early warning systems.

The Paris Agreement on Climate sets the international objective of reducing greenhouse gas (GHG) emissions to keep climate warming well below two degrees. However, quantifying past and present GHG emissions and sinks and predicting their future remains a substantial challenge. This challenge is primarily due to the high level of uncertainties in observing and modeling these GHG fluxes at regional to global scales. Thus, achieving climate and emission reduction targets requires a substantial improvement in our scientific ability to estimate the budgets and trends of these key major greenhouse gases (CO2, CH4 and N2O).

This session aims to bring together studies that seek to quantify past, present, and future global and regional budgets, trends and variability of major GHGs, as well as studies that contribute to understanding the key drivers and processes controlling their variations. We welcome contributions using a variety of approaches, such as emissions inventories, field and remotely sensed observations, terrestrial and ocean biogeochemical modeling, earth system modeling, and atmospheric inverse modeling. We encourage contributions integrating different datasets and approaches at multiple spatial (regional to global) and temporal scales (from past over the present and to the future) that provide new insights on processes influencing GHG budgets and trends in the past and future.

Anthropogenic disturbance of the global nitrogen (N) cycle has more than doubled the amount of reactive N circulating in the terrestrial biosphere alone. Exchange of reactive/non-reactive nitrogen gases between land and atmosphere are strongly affecting Earth’s atmospheric composition, air quality, global warming, climate change and human health. This session seeks to improve our understanding of a) how intensification of reactive N use, land management and climate change affects the pools and fluxes of nitrogen in terrestrial and aquatic ecosystems, b) and how reactive N enrichment of land and water will affect the future carbon sink of natural ecosystems as well as atmospheric exchanges of reactive (NO, N2O, NH3, HONO, NO2 and non-reactive N (N2) gases with implications for global warming, climate change and air quality. We welcome contributions covering a wide range of experimental and modelling studies, which covers microbes-mediated and physico-chemical transformations and transport of nitrogen across the land-water-air continuum in natural ecosystems from local to regional and global scales. Furthermore, the interactions of nitrogen with other elemental cycles (e.g. phosphorus, carbon) and the impacts of these interactive feedbacks for soil health, biodiversity and water and air quality will be explored in this session. Latest developments in methodological innovations and observational and experimental approaches for unravelling the complexities of nitrogen transformations and transport will also be of interest. This session will be celebrating its 10th anniversary for nitrogen science and cycling at the EGU2025.

In recent decades, extreme fire events have become increasingly common, exemplified by the recent fire seasons in Greece, Canada, Hawaii, California, Australia, Amazonia, the Arctic and the Pantanal. While these extremes and megafires have an exponential impact on society and all aspects of the Earth system, there is much to learn about their characteristics, drivers, links to climate change, and how to quantify their impacts, as well as mitigation and prevention strategies and tools.

One area of attention is how extreme fires are currently represented by different fire models. Due to their stochastic nature, uncertainty in observations, and the challenge of representing local processes within global models, extreme fires and their impacts still present a challenge to coupled modelling. The big data science models and machine learning approaches show promise in representing extremes but are weak in coupling feedbacks to vegetation, soils and the wider Earth System.

We also welcome case studies of regional extreme wildfire events, their impacts, and prevention and mitigation strategy experiences worldwide. We encourage contributions from a wide range of disciplines, including global, regional, and landscape modelling, statistical and process-based modelling, observations and field studies, science and social science studies on all temporal scales. In this session, we aim to share knowledge across multiple disciplines, from science to decision-makers and practitioners, to help overcome the challenges that wildfires pose to our models and our society.

We aim to explore the significance and interactions of extreme wildfires and their impacts on society and the earth system and identify the current gaps in our understanding to help us prepare for and mitigate future extreme wildfire events.

Fire has shaped the evolution of our species from the start. From presenting a danger to a valuable source of light and heat, fire and natural fire regimes presented a focal environmental factor for early hominins and homo sapiens. Reconstructing human interactions with and around fire is built on the investigation of heated materials or characteristic fire use features occurring in archaeological sites. In a first step this investigation requires the clear identification and differentiation of natural fires and post-depositional burning. Off-site fire use, including landscape burning and its impact on the environment by humans, is even more difficult to identify as this not associated
with archaeological remains, however, it can be investigated through other environmental archives such as sediment cores. The study of human fire use in the past, pyroarchaeology, employs both archaeological and geoscience methods to identify and characterize the material evidence of past fire events and relies on experimental and actualistic fire frameworks for behavioral inferences. This session aims to join researchers investigating paleo wildfires, past climate-human-fire-dynamics and related human interactions around fire and invites researchers that work in present fires and their effects on environment. From pyroarcheology to soil science, learning from past fires to understand better the current ones effects and vice versa.
Presentations involving the following topics are welcome:
• Prescribed and/or experimental fires;
• Human impact on fire regimes from sedimentary cores
• Fire history studies of archaeological periods
• Landscape burning practices
• Human fire use
• Methodological advances in fire research

Dissolved and particulate organic carbon (DOM, POM) are key components of the global carbon cycle and are important as potential sources of CO2 and CH4, and for the long-term preservation of carbon stabilized in subsoils and sediments. DOM and POM are important sources of energy for microbial metabolism within terrestrial ecosystems, the aquatic continuum, and, ultimately, the ocean. Despite recent evidence showing this lateral transport of carbon is linked to anthropogenic perturbations, efforts to integrate DOM and POM fluxes across the terrestrial-aquatic continuum are just emerging. A comprehensive understanding of the dynamics of DOM and POM, and their interactions, in terrestrial and aquatic ecosystems remains challenging due to complex interactions of biogeochemical and hydrological processes at different scales, i.e. from the molecular to the landscape scale.
This session aims to improve our understanding of organic matter processing at the interface of terrestrial and aquatic ecosystems. We solicit contributions dealing with amounts, composition, reactivity, and fate of DOM and POM and the stoichiometry of its constituents (i.e., C, N, P, S) in soils, lakes, rivers, and the ocean as well as the impact of land use change and climatic change on these processes. For example, when assessing carbon dynamics across the terrestrial-aquatic continuum, it is important to recognize the key role of peatlands and peat restoration efforts as sources of organic matter for streams and rivers, as well as the contribution of mineral soil horizons to C fluxes at the catchment scale. Contributions addressing lateral fluxes of sediment and carbon induced by soil erosion or permafrost thaw are also welcome. We aim to bring together scientists from various backgrounds, but all devoted to the study of dissolved and/or particulate organic matter using a broad spectrum of methodological approaches (e.g. molecular, spectroscopic, isotopic, 14C, other tracers, and modeling).

Phosphorus (P) is an essential element for life on Earth and is tightly cycled within the biosphere. Throughout geological history, P availability has regulated biological productivity with impacts on the global carbon cycle. Today, human activities are significantly changing the natural cycling of P. Phosphate mining threatens P reserves, while increased inputs of P to terrestrial ecosystems have enhanced fluxes of P to lakes and the oceans.

Direct anthropogenic perturbations of the P cycle, coupled with other human-induced stresses, have impacted numerous environments. Forest ecosystems may be losing their ability to recycle P efficiently, due to excessive N input, extensive biomass removal, and climatic stress. Soils, which serve as the biogeochemical fulcrum of the terrestrial P cycle, have been greatly altered by fertilizer use in recent decades. Changes in the P cycle on land impact the magnitude and timing of P fluxes into aquatic ecosystems, influencing their trophic state. Burial in sediments returns P to the geological reservoir, eventually forming economically viable P deposits. Throughout the P cycle, redox conditions play a key role in transformations and mobility of P. Climate change and its mitigation affect and will further disrupt global P cycles. For example, the removal of CO2 from the atmosphere through an increase in global soil organic carbon stocks implies P sequestration.

This interdisciplinary session invites contributions to the study of P from all disciplines, and aims to foster collaborations links between researchers working on different aspects of the P cycle. We target a balanced session giving equal weight across the continuum of environments in the P cycle, from agriculture, forests, soils and groundwater, through lakes, rivers and estuaries, to oceans, marine sediments and geological P deposits. We welcome both empirical and modeling studies.

Mercury (Hg) pollution, stemming from both intentional use and unintentional emissions, poses a global threat to human health and wildlife. The urgency of this issue has led 149 countries to join the Minamata Convention on Mercury, which has been in effect since 2017 and is currently undergoing its first effectiveness evaluation. Research into Hg biogeochemical cycling has revealed its ubiquity and complex transformations across various environmental compartments, including the atmosphere, oceans, cryosphere, soils, vegetation, biota, and the anthroposphere. Understanding the future trajectory of Hg pollution and its environmental impacts requires an in-depth knowledge of the processes occurring within and between these compartments. This session invites studies that investigate Hg cycling within individual compartments, as well as studies that explore inter-compartmental interactions and their influence on the Hg cycle. Topics of interest include, but are not limited to, air-surface exchanges of Hg compounds, Hg (de)-methylation and bioaccumulation, sea ice processing, and climate/global change impacts on Hg cycling. We welcome presentations utilizing diverse methodologies, including laboratory experiments, field studies, mechanistic or statistical modelling, paleoenvironmental records, genomics, Hg stable isotopes, and emissions projections. Additionally, this session encourages contributions that aim to inform policy, including those associated with the Multi-Compartment Hg Modeling and Analysis Project (MCHgMAP).

Animals are an integral part of the biosphere within the Earth system and a growing body of evidence suggests that, despite their small biomass compared to plants and microbes, the animals in terrestrial and aquatic biomes are important geoengineers of both the physical and chemical environment. Animals are involved in physical and chemical processes relevant for ecosystems at local and regional level and even at the planetary level. The role of animals are understudied as is reflected in Earth System Models, in which the biosphere and its interaction with the surrounding environment is largely represented by plants and microbes.
However, reintroducing large animals to restore ecosystem functioning and climate regulation and resilience, known as trophic rewilding, has become a global agenda, but knowledge on the direct and indirect effects of animals on the geophysical and chemical environment is scarce.
To address this, we invite contributions that study how animals shape Earth system processes. We welcome contributions across disciplines (ecology, geoscience), ecosystem types (terrestrial, aquatic), scales (field, ecosystem, planetary) and methodological approaches (field-based/lab-based, observational/experimental, modeling) that shed light on the role of animals in the Earth system from as many angles as possible. This could, for example, include how animals impact the physical environment through landscape (zoogeomorphology, e.g. beaver pond formation) and soil formation (e.g. bioturbation) or transformation and mediation of biogeochemical cycles (zoogeochemistry, e.g. carbon and nutrient cycling) through herbivore-plant-soil interactions.
With this session we want to spark interest in the broader geoscientific community of the intrinsic interaction of animals and earth system functioning and to shape the development of the emerging discipline of zoogeoscience.

Phenological changes induced by ongoing climate change are affecting species, ecosystems, and even the global climate by altering species performance, species interactions (potential mismatches and new opportunities in the food web), and water and carbon cycles. Observations of plant and animal phenology as well as remote sensing and modeling studies document complex interactions and raise many open questions about the future sustainability of species and ecosystems. In this session we invite all contributions that address seasonality changes based on plant and animal phenological observations, pollen monitoring, historical documentary sources, or seasonality measurements using climate data, remote sensing, flux measurements, modeling studies or experiments. We also welcome contributions addressing cross-disciplinary perspectives and international collaborations and program-building initiatives including citizen science networks and data analyses from these networks.
This session is organized by a consortium representing the International Society of Biometeorology (Phenology Commission), the Pan-European Phenology Network - PEP725, the Swiss Academy of Science SCNAT, the TEMPO French Phenology Network and the USA National Phenology Network.

The interactions between aerosols, climate, weather, and society are among the large uncertainties of current atmospheric research. Mineral dust is an important natural source of aerosol with significant implications on radiation, cloud microphysics, atmospheric chemistry, and the carbon cycle via the fertilization of marine and terrestrial ecosystems. Together with other light-absorbing particles, dust impacts snow and ice albedo and can accelerate glacier melt. In addition, properties of dust deposited in sediments and ice cores are important (paleo-)climate indicators.

This interdivisional session -- building bridges between the EGU divisions AS, CL, CR, SSP, BG and GM -- had its first edition in 2004 and it is open to contributions dealing with:

(1) measurements of all aspects of the dust cycle (emission, transport, deposition, size distribution, particle characteristics) with in situ and remote sensing techniques,
(2) numerical simulations of dust on global, regional, and local scales,
(3) meteorological conditions for dust storms, dust transport and deposition,
(4) interactions of dust with clouds and radiation,
(5) influence of dust on atmospheric chemistry,
(6) fertilization of ecosystems through dust deposition,
(7) interactions with the cryosphere, including also aerosols other than dust,
(8) any study using dust as a (paleo-)climate indicator, including sediment archives in loess, ice cores, lake sediments, ocean sediments and dunes,
(9) impacts of dust on climate and climate change, and associated feedbacks and uncertainties,
(10) implications of dust for health, transport, energy systems, agriculture, infrastructure, etc.

We especially encourage the submission of papers that integrate different disciplines and/or address the modelling of past, present, and future climates.

The Critical Zone (CZ), encompassing the Earth's outer layer from the top of the vegetation canopy to the bottom of the circulating groundwater, is essential for sustaining life and maintaining environmental health. Understanding this complex zone requires a collaborative, multidisciplinary approach that transcends disciplinary and national boundaries, bridging gaps between short-term and long-term environmental processes. This session will highlight CZ science, CZ methodologies, and the collaborative efforts of CZ networks from around the world. Topics of interest include, but are not limited to: Innovative techniques in CZ research and monitoring, including contributions involving observations, modeling, or integration of the two; Advances in understanding soils, hydrology, and biogeochemical cycling within the CZ; Characterization of CZ structure as it varies with depth and environmental factors; Impacts of stressors and environmental change on the CZ; Policy or management implications of CZ research; Development of CZ science networks; and Case studies of successful international CZ collaborations.

This session is open to all contributions in biogeochemistry and ecology where stable isotope techniques are used as analytical tools, with foci both on stable isotopes of light elements (C, H, O, N, S, …) and new systems (clumped and metal isotopes). We welcome studies from both terrestrial and aquatic (including marine) environments as well as methodological, experimental and theoretical studies that introduce new approaches or techniques (including natural abundance work, labelling studies, modeling).
Results from the successful EGU sessions on the ‘Application of Stable Isotopes in Biogeosciences’ that took place earlier have been published in several special issues of Organic Geochemistry and Isotopes in Environmental & Health Studies.

We welcome contributions involving the use of stable isotopes of light elements (C, H, O, N, S) or novel tracers (such as COS) in field and laboratory experiments, the latest instrument developments, as well as theoretical and modelling activities, which advance our understanding of biogeochemical and atmospheric processes. We are particularly interested in the latest findings and insights from research involving:

- Isotopologues of carbon dioxide (CO2), water (H2O), methane (CH4), carbon monoxide (CO), oxygen (O2), carbonyl sulfide (COS), and nitrous oxide (N2O)

- Novel tracers and biological analogues

- Polyisotopocules including "clumped isotopes"

- Non-mass-dependent isotopic fractionation and related isotope anomalies

- Intramolecular stable isotope distributions ("isotopomer abundances")

- Quantification of isotope effects

- Analytical, methodological, and modelling developments

- Flux measurements

This session aims to unite scientists employing stable isotope analyses of light elements (e.g., carbon, oxygen, hydrogen, nitrogen) to address ecophysiological questions concerning climate change and other abiotic and biotic stressors.

We invite researchers studying a variety of compounds (e.g., lipids, cellulose, lignin, non-structural carbohydrates, water) from both aquatic (e.g., fish, micro and macroalgae) and terrestrial (e.g., mosses, grasses, crops, trees) ecosystems. Contributions that span all spatiotemporal scales and archival materials (e.g., herbarium samples, peat, sediments, loess, tree rings) are welcome.

Researchers utilising a range of analytical isotopic techniques, including but not limited to IRMS, NMR, Orbitrap and spectroscopy-based methods, are encouraged to present their methodological advancements. By showcasing cutting-edge research and methodological innovations, we aim to highlight the crucial role of stable isotope analyses in ecophysiological studies and foster interdisciplinary collaboration.

We look forward to your contributions to this exciting and recurring session.

Lipid biomarkers are valuable tools for reconstructing a variety of environmental processes in modern and (geological) past settings. Application of lipid biomarkers includes analyzing the distribution and stable isotopic composition of core lipids (e.g., n-alkanes, fatty acids, alkenones, sterols, hopanoids, HBIs, HGs, and GDGTs) and intact polar lipids in the environment. Given complex relationships between biogenic organic compounds and environmental conditions, it is crucial to understand the mechanisms that influence their molecular distribution and isotopic composition in diverse depositional environments. This includes identifying biogenic sources, physiological effects, evidence of transport, post-depositional processes, and diagenesis.
We seek studies that develop new lipid biomarkers and methods for applying biomarkers to modern settings and the geologic past in order to reconstruct environmental parameters such as temperature, precipitation, biogeochemical cycles, anthropogenic activities, and vegetation. These can be studies on the biosynthesis and phylogeny of source organisms, transport and diagenesis, calibrations to environmental parameters, proxy interpretation and applications to reconstruct past environmental conditions.

Recent advancements in AI and the availability of big data through technologies like physical sensor networks and remote sensing are revolutionizing how we collect, process, and predict system dynamics. These emerging technologies have the potential to enable more accurate GHG (N2O, CH4, CO2) emission estimates and a better understanding of soil carbon dynamics across diverse ecosystems, which are crucial for achieving NetZero and tackling climate change. This session solicits papers that will explore various AI and machine learning approaches in conjunction with various data-driven inductive approaches such as causality analysis, time series modelling, and Bayesian statistics across space (point, landscape to region) and time (diurnal, weeks, seasons, inter-annual, and decadal).

We specifically encourage submissions that will provide a holistic view of AI-powered solutions for predicting ecosystem dynamics and guide policy decisions for effective climate mitigation and adaptation strategies (e.g., nature-based climate solutions).

The interplay between natural organic matter (NOM) and decomposer communities at the nexus of solids, solutes and volatiles regulates a C reservoir larger than all living biomass on Earth, making it a keystone in the global carbon cycle. Despite its ubiquitousness, NOM remains a black box due to its astonishing molecular complexity. Advances in ultrahigh resolution mass spectrometry (FT-ICR-MS, Orbitrap, TOF-MS) have enabled researchers to analyze NOM in all forms - solid, soluble and volatile - on the molecular-level. Ultimately, this allows to resolve the molecular complexity of NOM, and to elucidate its mediating role in various processes essential for life on Earth, such as energy flow, nutrient retention and resupply, or climate stability.

The challenge ahead of us is to synthesize the gained knowledge from various research communities (biogeochemistry, soil sciences, atmospheric sciences, aquatic sciences, analytical chemistry, geomicrobiology), ultimately providing useful data and process understanding to integrate in C cycle models that represent its molecular complexity in a more realistic way. To achieve this, it is also required to develop computational methods to align FT-ICR-MS data with complementary spectroscopic and mass spectrometric techniques (NMR, FT-IR, XPS, py-GC-MS, EEMs-PARAFAC, PTR-MS, etc.) and allow for a community-driven effort to share, curate and compare global molecular-level datasets.

In this session we therefore welcome proceedings in the following domains:
- Experimental, e.g. focusing on single or combined processes of NOM biogeochemistry or its links with other drivers such as microbial communities,
- Field-scale, e.g. studying the behavior of NOM across environmental gradients or interfaces,
- Modeling and simulation, e.g. integrating molecular-level data to improve the prediction of environmental processes or simulate ecosystem functioning,
- Computational, e.g. bioinformatic approaches to facilitate the analysis of molecular-level NOM data, or allowing its integration with complementary data streams,
- Analytical, e.g. improving or expanding the measurement of NOM on the molecular level, or providing novel tools to reveal its properties, responses or effects

We are looking forward to bringing together researchers from a wide range of disciplines to share their perspectives on studying NOM at EGU25!

Evapotranspiration (ET) is the key water flux at the interface of soil, vegetation and atmosphere. Methods to derive this flux or its individual components from in-situ measurements have been developed in various research disciplines, covering different scales from e.g. point scale sap flow or soil heat pulse measurements, via pedon-scale of lysimeters, ecosystem scale of eddy covariance footprints to the landscape scale via drones or scintillometers. In-situ-measurements are necessary for calibration, validation and comparisons with larger scale estimates from remote sensing and modelling, but scaling procedures and uncertainty estimations are required for meaningful comparisons. Additionally, the support of these processes by AI methods holds much promise, but usually depends on large well-described data sets.

This session will mainly focus on the variety of in-situ ET estimates such as from sap flow or soil heat pulse sensors, lysimeters, eddy covariance stations, scintillometers and other (possibly new) methods. We would also like to address the challenges in comparing the different in-situ estimates while dealing with scale-dependency, uncertainty and representativity. We welcome contributions that (1) assess and compare established and new in-situ measurements, (2) address error sources and uncertainty considerations of the respective methods, (3) bridge scales between different in-situ measurements and modelled and remotely sensed ET, (4) evaluate challenges and opportunities of using AI for in-situ scaling and comparisons.

Stable and radiogenic isotopic records have been successfully used for investigating various terrestrial and marine sequences, fossils, evaporative rocks, palaeosols, lacustrine, loess, caves, peatlands. In this session we are looking for contributions using isotopes along with sedimentological, biological, paleontological, mineralogical, chemical records in order to unravel past and present climate and environmental changes or as tracers for determining the source of phases involved. Novel directions using triple isotopes, clumped isotopes, biomarkers are welcomed.
The session invites contributions presenting an applied as well as a theoretical approach. We welcome papers related to reconstructions (at various time and space scales), fractionation factors, measurement methods, proxy calibration, and verification.

While the need for global cooperation in the face of global trends is obvious, funding mechanisms for environmental research and monitoring are still largely organised on a national and regional basis. Despite declared intentions to improve cooperation and thematic coordination in the formulation of related research and infrastructure programmes, concrete cooperation is hampered by a lack of resources and time for consultation, even in the case of thematically appropriate calls. This affects not only collaborative projects but also the improvement of interoperability and, ultimately, the concerted development and sustainable operation of services. Initiatives such as the G8 Group of Senior Officials (GSO) with its Recommendations for Global Research Infrastructures (GRI) have not led to a structural improvement of the situation. Still, Environmental Research Infrastructures (ENVRIs), have become a key instrument in environmental science and science-driven environmental politics.
Contributions to this session should present successful examples, experienced constraints and derived recommendations for action. They might address the value chain from open standardised observations and experiments data via scientific analysis towards societal impact through actionable knowledge, but also refer to,basic ENVRI activities like access to long-term operated in-situ facilities. An Impact Lecture will introduce the Global Ecosystem Research Infrastructures Initiative, in which SAEON/South Africa, TERN/Australia, CERN/China, NEON/USA, ICOS/Europe and eLTER/Europe will present their work on harmonised data systems, training and development, and collaboration in the use case 'ecological drought'.

Agrogeophysics harnesses geophysical methods such as ground-penetrating radar, electrical imaging, seismic,... from hand-held over drone to satellite-borne, to characterize patterns or processes in the soil-plant continuum of interest for agronomic management. These methods help develop sustainable agricultural practices by providing minimally-invasive, spatially consistent, multi-scale, and temporally-resolved information of processes in agro- ecosystems that is inaccessible by traditional monitoring techniques. The aim of this session is to feature applications of geophysical methods in agricultural research and/or show methodologies to overcome their inherent limitations and challenges. We welcome contributions monitoring soil or plant properties and states revealing information relevant for agricultural management; studies developing and using proximal or remote sensing techniques for mapping or monitoring soil-water-plant interactions; work focused on bridging the scale gap between these multiple techniques; or work investigating pedophysical relationships to better understand laboratory-scale links between sensed properties and soil variables of interest. Submissions profiting on data fusion, utilizing innovative modeling tools for interpretation, and demonstrating novel acquisition or processing techniques are encouraged.

The cycling of carbon (C) and key nutrients, such as nitrogen (N) and phosphorus (P), in soils is crucial for maintaining ecosystem health, agricultural productivity, and climate regulation. As global challenges, such as climate change, soil degradation, and nutrient imbalances intensify, there is a rising demand for advanced analytical methods that can unravel the complexities of these biogeochemical cycles.
The session aims to bring together experts from a broad range of disciplines, including soil science, biogeochemistry, analytical chemistry, and related fields, to discuss innovative analytical techniques that improve our understanding of C, N, and P cycling. We welcome discussions on the application of cutting-edge methods such as high-resolution spectroscopy, stable isotope techniques, molecular-level analyses, and other emerging approaches to address long-standing questions on the dynamics, interactions, and transformations of C, N, and P in diverse soil environments—from agricultural lands to natural ecosystems.
We invite contributions from researchers who are at the forefront of employing or developing these novel tools to decipher C, N, and P cycling in soil. This session will provide a platform for discussing the challenges, opportunities, and future directions in soil element cycling, fostering collaborations across disciplines.

The terrestrial vegetation carbon balance is controlled not just by photosynthesis, but by respiration, carbon allocation, turnover (comprising litterfall, background mortality and disturbances) and wider vegetation dynamics. Recently observed changes in vegetation structure and functioning are the result of these processes and their interactions with atmospheric carbon dioxide concentration, nutrient availability, climate, and human activities. The quantification and assessment of such changes has proven extremely challenging because of a lack of observations at spatio-temporal scales appropriate for evaluating trends and projecting them into the future.

This limited observation base gives rise to high uncertainty regarding the future terrestrial carbon sink. Many questions need answer to determine if it will be sustained under future environmental changes, or whether increases in autotrophic respiration or carbon turnover might counteract this negative feedback to climate change. For instance, will accelerated background tree mortality or more frequent and more severe disturbance events (e.g. drought, fire, insect outbreaks) turn vegetation into carbon sources? How will shifts in dynamics of plant mortality, establishment, and growth influence forest composition?

Uncertainties and/or data gaps in large-scale empirical products of vegetation dynamics, carbon fluxes and stocks may be overcome by extensive collections of field data and new satellite retrievals of forest biomass and other vegetation properties. Such novel datasets may be used to evaluate, develop and parametrize global vegetation models and hence to constrain present and future simulations of vegetation dynamics. Where no observations exist, exploratory modelling can investigate realistic responses and identify necessary measurements. We welcome contributions that make use of observational approaches, vegetation models, or model-data integration techniques to advance understanding of the effects of environmental change on vegetation dynamics, tree mortality as well as carbon stocks and fluxes at local, regional or global scales and/or over long periods.

Human activities on land (LULCC) shape climate by altering land-atmosphere fluxes of carbon, water, energy, and momentum. An increasing focus on land-based climate mitigation and adaptation strategies to meet more stringent targets has expanded the range of land management practices considered specifically for their potential to alter terrestrial carbon cycling or mediate favorable environmental conditions. This focus has also called attention to potential tradeoffs between climate-centric aspects of LULCC and its influences on biodiversity, hydrology and other environmental factors. Advancements in modeling and measurement techniques are opening new possibilities to better describe LULCC and its effects on the Earth system at multiple temporal and spatial scales.

This session welcomes all contributions aimed at furthering our understanding of LULCC in the Earth system, including those addressing LULCC effects on carbon, climate, hydrology, and/or biodiversity, and aims to present studies that can inform adoption of appropriate land-based strategies for climate mitigation, adaptation, and ecosystem restoration.

Plant traits extend the range of earth observations to the level of individual organisms, providing a link to ecosystem function and modelling in the context of rapid global changes. However, overcoming the differences in temporal and spatial scales between plant trait data and biogeochemical cycles remains challenging.

This session will address the role of plant traits, biodiversity, acclimation, and adaptation in the biogeochemical cycles of water, carbon, nitrogen, and phosphorus. We welcome conceptual, observational, experimental and modelling approaches and studies from the local to the global scale, including in-situ or remote sensing observations.

Although climate change is a natural process, it is significantly stimulated by anthropogenic activities. The acceleration of climate change is directly connected with ecological stability, soil degradation, and hydrological extremes, which are considered as the main consequences of climate change. As climate change intensifies, extreme and unexpected weather events are becoming more frequent.
The aim of this session is to highlight a broad range of research methods and results related to climate change. This interdisciplinary session should reflect, discuss, and share scientific knowledge on a local and regional scale with the aim to increase innovative knowledge on climate change and its impacts, ecosystem response and new techniques to prevent and reduce the negative consequences.

This session encourages contributions from several fields related to:
- climate change impacts (biodiversity loss, rising temperatures, hydrological extremes, soil degradation, ecosystem response to climate change);
- droughts and floods; precipitation deficiency or extreme precipitation with solutions aimed at reducing the negative impacts;
- ecological stability and climate change; changes of ecological stability, deforestation, human interactions with the environment and evaluation of restoration success;
- green cities to increase the ecological stability of the urban landscape;
- techniques and methods to prevent and reduce the negative impacts of climate change (such as soil degradation, carbon sequestration, changes in natural, agricultural, and forest ecosystems, reduction of overall ecological stability and character of the landscape);
In addition, attention will be given to the sustainability of management practices, the importance of appropriate land use management as the main tool for preventing the degradation processes, the distribution and vitality of ecosystems, and improving the condition of forest ecosystems in order to increase the overall character of the landscape.

Human activities are altering a range of environmental conditions, including atmospheric CO2 concentration, climate, and nutrient inputs. Understanding and predicting their combined impacts on biogeochemical cycles, ecosystem structure and functioning is a major challenge. Divergent future projections of terrestrial ecosystem models reveal uncertainties about fundamental processes and missing observational constraints. Models are routinely tested and calibrated against data from ecosystem flux measurements, remote sensing, atmospheric inversions and ecosystem inventories. However, it remains challenging to use available observations to constrain process representations and parameterizations in models simulating the response of ecophysiological, biogeochemical, and hydrological processes to environmental changes.

This session focuses on the influence of CO2, temperature, water stress, and nutrients on ecosystem functioning and structure. A focus is set on learning from manipulative experiments and novel uses of continuous ecosystem monitoring and Earth observation data for informing theory and ecosystem models. Contributions may cover a range of scales and scopes, including plant ecophysiology, soil organic matter dynamics, soil microbial activity, nutrient cycling, plant-soil interactions, or ecosystem dynamics.

The need to predict ecosystem responses to anthropogenic change, including but not limited to changes in climate and increased atmospheric CO2 concentrations, is more pressing than ever. Global change is inherently multi-factorial and as the terrestrial biosphere moves into states without a present climate analogue, mechanistic understanding of ecosystem processes and their linkages with vegetation diversity and ecosystem function is vital to enable predictive capacity in future forecast tools.

This session is about process understanding of scalable ecophysiology and ecosystem function relevant to carbon and water cycles, above- and below-ground. We facilitate dialogue across scales and techniques, from mesocosm experiments to field experiments, remote sensing and modelling.

A robust representation of terrestrial carbon, energy, and water cycles requires a fundamental understanding of biosphere-atmosphere interactions, particularly in the context of a rapidly changing climate. However, a significant challenge arises from the mismatch that occurs when carbon, water, or energy fluxes are measured or modelled at different spatio-temporal scales. Multiple processes determine how mass and energy exchanges scale from the leaf, to the whole plant, to the ecosystem, and eventually to the globe. Despite the evolution of Earth system models to incorporate increasingly complex processes across these scales, uncertainties persist due to these mismatches. The unprecedented rate of climate change, along with the increasing frequency and intensity of extreme events, further complicates our ability to robustly formulate mechanistic underpinnings of biogeochemical processes across scales.
The increasing volume of data at multiple scales—from leaf-level measurements (e.g., gas exchange), tree-level measurements (e.g., sap flow and dendroecology), ecosystem-level measurements (e.g., eddy covariance towers, UAVs, aircraft), to Earth observation from space—presents new opportunities to address these challenges. This session invites studies that improve our overall understanding of biosphere-atmosphere interactions by addressing the mismatches across different temporal and spatial scales and integrating these insights into modeling strategies. We particularly encourage contributions that explore the effects of climate extremes (e.g., drought, heatwaves, excess rainfall, winter warming) on carbon, energy, and water fluxes. In addition to empirical multi-scale observations, we welcome research that delves into data-driven diagnostics and constraints for model evaluation, data-driven parameterisations in mechanistic models, and the development of data-driven/hybrid modelling strategies (i.e., seamless fusion of data-driven approaches and mechanistic models) for an integrated understanding of carbon, energy, and water fluxes across scales.

This session aims to bring together scientists actively engaged in ecosystem modelling to discuss recent advancements in developing ecological processes and constraining climate responses within models. As climate changes continue to impact ecosystems worldwide, improving the presentation of processes, responses and their interactions is crucial for accurately predicting future responses and gaining insights into terrestrial feedback mechanism atmospheric feedback.

We invite abstracts that address, but are not limited to, the following themes:
(1) Advances in representing responses of terrestrial ecosystem processes to climate variability and extremes;
(2) Advances in accounting for species dynamics, changes in ecosystem composition and interactions;
(3) Methods for improving the representation of ecological processes and interactions in different terrestrial ecosystems;
(4) site, regional and global studies taking advantage of in-situ measurements, Earth observing systems (EOS) or laboratory experiments, improving ecosystem model processes

The microclimate within terrestrial ecosystems is highly heterogeneous as it responds to a multitude of local and landscape-scale factors such as foliage density, micro-topography, distance to a forest edge or a water body. This diversity of microclimates, and the potential buffering of climate extremes in the landscape, are key to understand terrestrial biodiversity and ecosystem functioning (notably carbon, water and nutrient cycling), but also ecosystem resilience and feedback onto regional climate. Despite our good understanding of the biophysical processes driving microclimate, it is still very challenging to describe and predict how microclimate varies across the landscape, and anticipate the impact of changes in climate, land use or ecosystem management.
In this session, we welcome observational, experimental and modelling studies on terrestrial microclimate, its role on biodiversity, biogeochemical cycles, ecosystem resilience and its response to climate and land use change.

Extremes in temperature, vapor pressure deficit, and soil moisture severely endanger critical functions and services provided by terrestrial ecosystems. Both increasingly extreme long-term trends in environmental conditions and extreme events such as heatwaves, droughts, floods, and unseasonal freezes directly impact key physiological processes such as carbon uptake, transpiration, growth, and mortality. An abundance or scarcity of water, atmospheric dryness, heat, and cold can operate separately or in tandem to cause reductions in terrestrial gross and net primary productivity and elevated risks of plant mortality. However, due to the complexity of these interactions and the scarcity of continuous time series, it is difficult to quantify the magnitude and timing of temperature and water stress-related impacts on ecosystem function. As climate change accelerates the occurrence and severity of climatic extremes with consequences for terrestrial ecosystems, we must harmonize our efforts to characterize plant and ecosystem functions and develop frameworks for monitoring and prediction.

In this session, we broadly explore the roles of temperature extremes, evaporative demand, and soil moisture in carbon, water, and energy relations, along with plant mortality across various spatial and temporal scales. We encourage submissions dealing with novel approaches for measuring and modeling plant and soil water status, responses to extreme conditions, and their impacts on ecosystem function. We invite contributions on these topics at scales ranging from individual plant tissues to entire ecosystems, applying experimental, observational, or modeling approaches and dealing with diverse disciplines such as plant physiology, community ecology, ecosystem ecology, land management, and biogeochemistry.

Tropical ecosystems are biomes of global significance due to their large biodiversity, carbon storage capacity, and their role in the hydrological cycle. Historical and recent human activities have, however, resulted in an intensive transformation of the tropical ecosystems in the Amazon, Central America, Central Africa and South East Asia, impacting the cycling of nutrients, carbon, water, and energy. Understanding their current functioning at process up to biome level in its pristine and transformed state is elemental for predicting their response to changing climate and land use and the impact this will have on local up to global scale.
The purpose of this session is to unite scientists investigating the dynamics of tropical ecosystems, employing a range of remote and on-site observational, experimental, modelling, and theoretical approaches. We are particularly interested in studies evidencing/documenting how tropical biomes, at the local or regional scale, respond to human-induced disturbances and climate change. In particular, spatial gradients and temporal scales that mirror global changes. Moreover, we encourage the presentation of innovative interdisciplinary methodologies and techniques that have the potential to reshape existing paradigms, thereby paving the way for exciting new avenues of exploration.

Forest disturbance regimes (i.e. size, frequency and severity) are expected to change as global warming intensifies, thus affecting the productivity, growth and vitality of vegetation. For instance, hotter droughts are leading to widespread canopy dieback episodes rising tree mortality rates. Understanding and quantifying forest vulnerability to such disturbances and the underlying driving mechanisms is crucial to assess climate impacts and develop effective adaptation strategies.
This session will cover aspects ranging from observed and projected climate change to consequences for forest ecosystems and their assessment, spanning a range of scales, biomes and conditions. In particular, we welcome submissions on the following subjects:

• Evaluation of the effects of natural and anthropogenic disturbances on forest productivity, health and growth.
• Multidisciplinary approaches for monitoring tree vulnerability at the local, regional and global scales.
• Mapping and forecasting forest mortality and dieback phenomena under different climate and land-use scenarios.
• Modelling climate and environmental influences on forest and tree vigor and growth at different scales and considering different methods or processes (e.g., wood formation, leaf phenology, shoot growth, canopy greenness).
• Vulnerability of old-growth and mountain forests and also old trees to climate change.
• Assessing forest resilience to drought and other extreme climate events (e.g., frosts).
• Using adaptive management to buffer forest vulnerability.
• Methods and tools for decision support and adaptation support in the forestry sector considering multiple stakeholders and multifunctional perspectives.

Mycorrhizal fungi are central to the functioning of forest ecosystems, playing a critical role in ecological processes such as nutrient cycling and carbon storage. Mycorrhizal fungi enhance nutrient uptake by trees, forest productivity, influence decomposition, and they contribute to organic matter accumulation. This session aims to bring together research investigating the diverse roles and functions of mycorrhizal fungi in forest ecosystems, with a focus on ectomycorrhizal, arbuscular, and ericoid mycorrhizal associations. We will explore how mycorrhizal fungi drive ecosystem functioning in its broadest sense, and how these processes respond to environmental changes, from climate change to forest management. We welcome contributions from research conducted across various forest biomes and scales, ranging from the global to petri dish scale, encompassing observational, experimental, and modeling approaches. By fostering discussion and sharing cutting-edge research, this session aims to deepen our understanding of mycorrhizal fungi in forest ecosystems, clarify their ecological importance, and highlight the need for continued exploration in this rapidly evolving field.

Deadwood is a multifunctional and dynamic feature of forest ecosystems, both terrestrial and aquatic, as it is a hotspot of biodiversity, carbon and forest soil functioning. In particular deadwood has a positive effect on soil health by improving basic properties that are important for the structure and diversity of soil microorganisms. Forest resilience thus can be improved when deadwood supports tree growth through increased water retention, nutrient availability and soil organic carbon stocks especially when stressed by e.g. drought. Yet resilience can be reduced when deadwood heightens the risk and intensity of forest fires, pathogens, and pests. To evaluate deadwood’s contribution to climate resilience via biodiversity, soil functions, (soil) water dynamics, carbon fluxes and fire, we need a better understanding of deadwood quantities and characteristics in forests, underlying faunal and microbial biogeochemical dynamics, and wood decomposition from the canopy to subsoil. Particular interest is placed on the deadwood-soil interface under different environmental conditions and management regimes.

The aim of this session is to illuminate the complex role of deadwood in forest ecosystems by addressing its full range of functions, discussing methods for interdisciplinary deadwood research and deriving implications for sustainable and climate mitigating forest management. We are looking for contributions on classification and quantification of deadwood stocks at different scales, deadwood fauna, fungi, and microbial community dynamics; decomposition processes, the deadwood-soil interface, the potential of deadwood for carbon sequestration (under different environmental conditions), the hydrological effects of deadwood and forest fire risk. Exploratory studies as well as experimental or modelling approaches are welcome.

Forest ecosystems in tropical, subtropical, and semi-arid regions face heightened risks of tree mortality due to various natural and human-induced disturbances such as prolonged droughts, extreme weather events, pest outbreaks, and diseases. These ecosystems, often underrepresented in global research, play critical roles in biodiversity, carbon sequestration, and the livelihoods of millions. Their degradation can lead to significant losses in ecosystem services, which makes understanding the causes and mechanisms of forest dieback in these regions especially urgent.

This session invites contributions exploring forest vulnerability to disturbances in tropical, subtropical, and semi-arid regions, focusing on observed impacts and predictive models. We aim to cover a broad range of topics, from local to global scales, to foster a deeper understanding of the pressures on these crucial ecosystems and how to manage their resilience.

Topics of Interest:
- Mapping and predicting tree mortality and dieback phenomena in underrepresented regions under global climate change.
- The effects of natural and anthropogenic disturbances on forest health, growth, and mortality, particularly in tropical and semi-arid regions.
- Attribution of excess tree mortality to climate change or climate extremes.
- Quantification of excess tree mortality (as opposed to background / average mortality).
- Vulnerability of old-growth forests and other critical habitats to environmental stressors.
- Multidisciplinary approaches for studying tree mortality and forest vulnerability across scales with a focus on data-scarce regions
- Evaluating forest resistance and resilience in drought-prone areas of the tropics and subtropics.
- Interdisciplinary research integrating ecological, economic, and social factors in forest management.
- Assessing the effectiveness of adaptive management strategies in improving forest health and reducing vulnerability.
- Tools and methods for decision support and adaptive management in forestry, particularly in regions facing extreme climatic conditions.

This session aims to bridge gaps in research on forest mortality in underrepresented regions, providing a platform for sharing new insights and strategies for enhancing forest resilience under the pressures of climate change. We welcome research that leverages data and techniques from satellite/aerial/proximal remote sensing and field ecology.

Droughts are expected to increase in extremity, duration and frequency with climate change. This expected intensification of drought events is likely to have profound, but largely unknown, impacts on terrestrial ecosystems in many regions of the world. Extreme droughts by definition naturally occur infrequently and those that are both prolonged and extreme are even rarer in their occurrence. As such, a growing number of experiments have been conducted to understand the impacts of intensified droughts. The goal of this session is to provide an overview of experiments addressing how intensification of drought affects terrestrial ecosystem structure and functioning and the potential mechanisms underlying variation in ecosystem response to intensified drought.

Biogeochemistry, ecology, and hydrology play crucial roles in shaping biotic processes, influencing both the cycles of water and essential elements (C, N, P), as well as the distribution, structure, and functioning of ecosystems. This session focuses on arid and semi-arid environments, particularly in the Global South, where substantial knowledge gaps still exist.

The session seeks to consolidate recent research on biogeochemical processes, with the following objectives:

To provide a comprehensive synthesis of current research approaches in these fields.
To highlight the role of soil-vegetation-atmosphere interactions, nutrient cycling, and biogeochemical and ecohydrological controls on nutrient availability in arid and semi-arid ecosystems.
We invite contributions that address:

Soil-vegetation-atmosphere interactions in arid and semi-arid regions.
The circularity of nutrients in these ecosystems.
Controls of biogeochemical and ecohydrological processes on soil and plant nutrient availability.
This session will offer an opportunity for researchers to share findings, discuss emerging methodologies, and contribute to a broader understanding of how these critical processes function in water- and nutrient-limited environments.

Permafrost soils are one of the largest and most vulnerable terrestrial carbon and nitrogen pools. Right now, we observe that global warming is leading to drastic landscape changes and widespread permafrost thaw. Coastal erosion is aggravating, the boreal tree line is shifting northwards, tundra fires are becoming more frequent and the degradation of peatlands with permafrost is increasing. The ongoing increase of temperature will enhance microbial decomposition of long-term stored soil organic matter and might eventually turn permafrost soils into a significant source of greenhouse gases. In addition, the degradation of permafrost increases the export of dissolved organic carbon, nutrients and pollutants into waterbodies impacting primary production and human health. We encourage submissions focusing on organic and inorganic carbon as well as on other elements such as nitrogen, phosphorus, silica, iron, mercury and others, from all parts of the global permafrost area including mountain, inland, coastal and subsea permafrost, on all spatial scales, in the contemporary system but also in the past and future, based on field, laboratory and modelling work.

The cold season dominates most of the year in Arctic and high latitude regions but is understudied due to difficult access and challenging working conditions. Nonetheless, plant and microbial activity and biogeochemical turnover continues during the non-growing season under snow cover and sub-zero temperatures. Such activity is likely to play an important role in year-round biological activity and ecosystem functioning, greenhouse gas fluxes, and nutrient cycling.
High latitude climate change is particularly pronounced during winter - where changing weather including extreme winter warming events, rain-on-snow events, and variable snow melt dates may substantially alter the physical, chemical and biological characteristics of terrestrial ecosystems and ecosystem interactions. However, there is a lack of data and understanding of the disruptions to soil-microbe-plant-snow-atmosphere interactions and ecosystem functioning resulting from changing winter conditions. Addressing the cold-season knowledge gap will bring us closer to a more comprehensive understanding of high latitude ecosystems and responses to seasonal and climatic changes.
In this interdisciplinary session, we aim to attract researchers working on the themes of Arctic and high latitude cold season biogeochemistry, microbiology and plant-soil processes. We want to bring multiple varied perspectives from different ecosystem constituents together, forming an integrated ecosystem approach that considers drivers, transformations, feedbacks, and interdependencies. We welcome studies focusing on experimental and modelling approaches to understand Arctic winter plant and microbial functioning, biogeochemical cycling, and associated impacts on the growing season, responses to changing Arctic seasonality, and winter climate regimes.

Arctic and alpine tundra ecosystems are changing fast in response to ongoing climate change and increased human pressures linked to land use changes. One observed phenomenon in response to these changes is the northward and upward shift in the distribution of temperate or boreal species from southerly latitudes or lower elevations, a process known as borealization. Examples of tundra borealization include the encroachment of woody species, the spread of non-native species, and changes in the composition of plant, animal and microbial communities. Borealization also alters the trophic and functional structure of ecosystems, changes landscape structure and impacts ecosystem processes such as the strength of carbon sink and sources.

This session aims to address the drivers, processes, and consequences of the borealization of tundra ecosystems, as well as its quantification from the perspectives of different disciplines, such as biogeography, remote sensing, (historical) ecology, and forest sciences. Multi-, inter- and transdisciplinary approaches are particularly welcome.

Northern peatlands contain large reservoirs of carbon and are targets for both protection and restoration, serving as critical buffers against climate change. We seek to understand responses of northern peatlands to natural and anthropogenic stressors and disturbances, and how these stressors could potentially shift these systems between functioning as sinks and sources of greenhouse gasses. Changes in the overall ecosystem structure and function are also of interest. We welcome submissions involving experimental manipulations, anthropogenic modifications, gradient studies, and other short- and long-term climate or environmental changes in both natural and restored peatland ecosystems. We welcome modelling studies that use theoretical approaches and observational data to understand current functions and predict future peatland carbon trajectories. Studies are solicited which investigate any combination of overall carbon, chemical, and hydrological balance, by observing total ecosystem and soil fluxes, net ecosystem exchange and respiration, moss and vegetation turnover and succession, microbial community composition and function, and porewater and nutrient chemistry.

Permafrost peatlands are found across the permafrost region. While the dominant landforms of permafrost peatlands vary, these fragile ecosystems have acted as natural sinks for atmospheric carbon for millennia and store a globally significant portion of the terrestrial soil organic carbon pool. Intact permafrost peatlands are vital components of the northern hydrological system, regulating local water levels through interactions with both groundwater and surface water networks, storing water and dampening hydrologic responses, and acting as sources of organic matter and potential contaminants for aquatic ecosystems. They provide key habitats for birds, mammals, and highly biodiverse vegetation. As a result, permafrost peatlands provide key ecosystem services, including the provision of traditional medicines, food, and drinking water for indigenous and local communities. Warming temperatures have recently driven widespread permafrost thaw and thermokarst formation, transforming these peatlands and causing drastic shifts in their biogeochemistry, hydrology, ecology, and morphology. Model projections indicate that within decades permafrost peatlands across the northern circumpolar permafrost region are likely to undergo rapid changes resulting from thaw, with complete permafrost losses likely to occur in the southernmost regions of this bioclimatic envelope. Establishing the response trajectories of these ecosystems to climate warming is critical for accurately projecting future environmental change.
The goal of this session is to facilitate interdisciplinary discussion on the dynamics of permafrost peatlands under a rapidly changing climate, and to explore the mechanisms driving change in these ecosystems. To achieve this, we encourage submissions across disciplines related to permafrost peatlands, using a wide range of methods such as field observation, palaeoecology, laboratory experiments, modelling and simulations, remote sensing, and data synthesis and analysis. We particularly encourage studies on 1) carbon and nutrient biogeochemical cycling (including stocks, fluxes, and upscaling efforts), 2) export of carbon, nutrients, and contaminants and their impact on aquatic ecosystems, 3) records illustrating thaw-related changes to hydrology and vegetation, 4) remote sensing methods for detecting changes, 5) the impact of disturbances (both natural and anthropogenic), and 6) the impact of a changing permafrost peatland landscape on northern communities.

Peatland restoration for conservation purposes has been implemented for decades now, but recently the focus has been shifting towards a reconciliation of the production of biomass with ecological goals, especially the reduction of greenhouse gas (GHG) emissions. Whilst peatland management in conservation-focussed projects increasingly has to be adapted to climate change. Management measures include, but are not limited to, productive use of wet peatlands (paludiculture), improved water management in conventional agriculture and innovative approaches in conservation-focused rewetting projects and dual-management for renewable energy production and peatland protection. We invite studies addressing all types of peatland management and their impacts on GHG exchange, ecosystem services and biodiversity. Work at all spatial scales from laboratory to global level addressing biogeochemical and biological aspects as well as experimental and modelling studies are welcome. Furthermore, we invite contributions addressing policy coherence and identifying policy instruments for initiating and implementing new management practices on organic soils. Implementation and efficiency of management practices depends not only on hydrogeology and climate but also on other regional factors. Therefore, we hope to host contributions from different geographical regions where peatlands are important including boreal, temperate and tropical peatlands.

Tropical peatlands are potentially the most carbon-dense ecosystems on earth but estimates of their total extent and carbon storage remain highly uncertain. In a natural condition, tropical peatlands are long-term C stores and support livelihoods, but anthropogenic disturbances (logging, drainage, degradation, agricultural conversion, fire, resource exploration) are increasing. These transformations result in high C loss, reduced C storage, increased greenhouse gas (GHG) emissions, loss of hydrological integrity, peat subsidence and increased risk of fire. For agricultural peatlands, changes in nutrient storage and cycling necessitate fertilizer use, with enhanced emissions of N2O. Under a warming climate, these impacts are likely to intensify and reduce the benefits to rural communities. This session welcomes contributions on all aspects of tropical peatland science, including peatland mapping and monitoring; the impact of climate on past, present and future tropical peatland formation, accumulation and C dynamics; GHG and nutrient flux dynamics; management strategies for GHG emissions mitigation and the maintenance or restoration of C sequestration and storage; and valuing ancestral knowledge of peatlands. Field based, experimental, modelling and palaeoecological studies of intact and modified systems from all tropical regions are welcomed.

For centuries peatlands have been recording humanity's toxic legacy. Pollutants, such as toxic metals and metalloids (e.g., lead, mercury, arsenic), hydrocarbons (e.g., heating oil, petroleum), or emerging contaminants (e.g., microplastics, forever chemicals), often accumulate in peatlands, resulting in elevated pollutant levels relative to mineral soil ecosystems. While at lower concentrations, such pollutants are tolerated in peatlands, higher levels can degrade the peatland processes that underpin critical peatland functions, such as carbon cycling, ecohydrology, or vegetation/microbial communities. These changes can not only impact the peatland itself, but also the wider landscape the peatlands are situated within. Additionally, disturbances like wildfire or drought can remobilise these stored pollutants to downstream ecosystems, potentially leading to environmental and human health issues decades (or even centuries) after the pollution was released.

We invite topics on the wide range of peatland pollutants and their impacts on peatland and landscape processes, with a focus on understanding the underlying biogeochemical, ecohydrological or biological mechanisms that support peatland function. Given the widespread nature of polluted peatlands, we are keen to represent a range of spatial scales (soil pore to global) using a variety of laboratory experiments, physicochemical measurements/monitoring, and/or numerical modelling techniques from a range of disciplines (e.g., biogeochemistry, ecology, microbiology, ecohydrology).

Peatlands serve as crucial carbon reservoirs and archives of past environmental changes. Being sensitive to climatic and anthropogenic influence, they store information on past vegetation, land-use, and human impact. Observed shifts in precipitation patterns and warming trends have exacerbated anthropogenic impacts, affecting peatlands' hydrology and carbon balance. Therefore, peatland palaeoecological studies are crucial to provide a long-term view of peatland evolution and resilience which can be used to predict future peatland conditions and development, and to support informed peatland restoration and conservation management. For the session, we invite contributions that utilize various biotic and abiotic proxies to explore questions centered around climate, disturbance, and human impacts on peatlands across different geographical regions and timescales. We strongly encourage abstracts that deepen the knowledge of all aspects of peatland ecology, evolution, and functioning, including (1) peat initiation and peat accumulation dynamics, (2) vegetation and hydrological changes through time, (3) identification of tipping points or resilience in peatland development, (4) evidence of direct anthropogenic pressure such as peat extraction, melioration or pollution, (5) new proxy development and calibration studies, as well as other related topics. We invite presentations that elucidate these complex relationships and contribute to understanding how peatlands respond to global change or may develop after restoration. We look forward to insightful contributions and engaging discussions in palaeoecology that will enrich our knowledge of peatlands in the modern era and about their future development.

Oxidation of peat organic carbon is a critical determinant of greenhouse gas emissions from peatland ecosystems. This session aims to bridge the gap between biogeochemical processes at the pore scale and their environmental impacts at the ecosystem scale.

At the heart of peat carbon oxidation are microorganisms that act on molecular carbon substrates, driving biogeochemical reactions at a microscale. These microbial processes are fundamental, yet they operate on a scale that poses challenges for direct observation and measurement. Our current methodologies allow us to measure processes at intermediate scales, providing valuable data on carbon turnover and peatland dynamics. However, there remains a significant challenge in inferring processes at the microscale and extrapolating or linking these drivers to the ecosystem scale, on which the implications of carbon emissions and climate change are most profound.

This scientific session will focus aims to integrate across the multiple scales of peat carbon oxidation. We will explore:

1. Microscale Processes: Understanding the role of biogeochemistry and microorganisms in peat decomposition and the processes that determine peat carbon oxidation potentials and rates
2. Intermediate-Scale Measurements: Applying techniques and methodologies to measure carbon turnover and emissions, the insights they provide in underlying processes, and techniques for up-scaling
3. Challenges in Up-scaling: Addressing the links between small-scale processes and ecosystem-scale emissions. This includes modeling approaches and integrative methods to connect scales.

Our goal is to foster a dialogue that integrates these different scales of study, ultimately enhancing our ability to predict and manage the effects of peat carbon oxidation on the global carbon cycle. By integration across scales, we aim to advance our understanding of peatland functioning and to develop more accurate models reflecting the true complexity of peatland ecosystems.

Join us in this session to contribute to a comprehensive understanding of peat carbon oxidation and its far-reaching implications.

Soils sustain complex patterns of life and act as biogeochemical reactors producing and consuming a large amount of gas molecules. They play a fundamental role in the temporal evolution of concentrations of many gas species in the atmosphere (greenhouse gases, biogenic volatile organic compounds, nitrous acid, isotopic composition…). On the other hand, the specific gas concentration in the soil may differ substantially from the typical atmospheric concentrations and can also affect many soil functions, such as root and plant growth, microbial activity, and stabilization of soil organic carbon. Thus, the production, consumption and transport of gases in the different soil types have important ecological implications for the earth system.
The factors affecting the soil gas processes range from physical soil structure (porosity, soil texture and structure,…), type and amount of living material (microbiota, root systems), soil chemical properties (carbon and nitrogen contents, pH,…) and soil meteorological conditions (temperature, water content,…). Different scientific backgrounds are therefore required to improve the knowledge about their influence which is made even more difficult due to the very large spatial heterogeneity of these factors and the complexity of their interactions.
This session will be the place to present and exchange about the measurement techniques, data analyses and modelling approaches that can help to figure out the temporal and spatial variability of the production/consumption and transport of gases in soils. In addition to mechanisms related to carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), including the geochemical cycles, also abstracts about volatile carbon compounds produced by plant and microbes, or phenomena including noble gases such as Helium and Radon are highly welcome A special attention will be given to the research including critical situations such as drought or waterlogged soils, and special gas transport phenomena in soils including plant mediated gas transport.

Soil carbon pools are much larger than the atmospheric C pools. Therefore, investigation into how microbial and plant processes in soils impact overall stabilization versus release of carbon into our environment is essential in driving our understanding of global carbon fluxes that drive climate change. Soil respiration is a major component of global carbon fluxes and can act as a net carbon dioxide (CO2) sink or net source depending on how ecosystems evolve. On the other hand, below ground and above ground volatile organic compounds act as a source of signals that mediate biogeochemical processes and are emitted in response to environmental changes, acting as an indicator of ecosystem health. Moreover, these microbial and plant gas phase emissions affect both soil and atmospheric processes.
This session is focused on the intersection between biogeochemical and atmospheric processes by showcasing experiments that combine soil and gas phase measurements including characterization of respiration, gas production/utilization and production and evolution of volatiles. We invite both field and laboratory studies representing soil carbon efflux measurements, microbial/plant volatiles as well as other gas phase soil and atmospheric emission that advances our understanding of biogeochemical processes.

Biogeochemical models inadequately capture microscale soil carbon effects, leading to conflicting portrayals of soils as carbon sinks or sources under climate change. New models, though promising, face challenges due to scarce data and variable microscale ecosystem processes, with variations reflecting microbiome diversity, and encompassing the physiological, hydrological, as well as mineralogical characteristics of soil microhabitats shaped by past selection.

This session will present interdisciplinary insights into soil carbon dynamics, examining how microscale interactions and microbial diversity affect carbon and nutrient cycles. Topics will include empirical data integration, data synthesis, harmonization of datasets, exploration of unifying principles governing nutrient cycling and energy flows, and their responses to environmental perturbations. We will also explore model parameterization challenges, trade-offs in model complexity, optimality based models in trait selection, and hierarchical multi-model approaches for improved climate model scaling. We welcome contributions from global change experiments using time-series metagenomic data and diversity-explicit microbial models, and encourage dialogue between marine and terrestrial research communities.

Pyrogenic organic matter (PyOM) can derive from natural (e.g., wildfire charcoal), as well as anthropogenic sources (e.g., biochar). Due to pyrolysis, PyOM is a highly condensed, aromatic material which is recognized as an important carbon sink in terrestrial and aquatic systems. With the potential to make wildfires a net sink of carbon or enhance carbon storage when applied in soils as biochar. Depending on its properties, PyOM can influence physical-, chemical-, and microbial soil functions. This can include, for example, releasing aromatic compounds, sorbing native organic matter, changing redox- and pH conditions, disintegrating into micro- and nanoparticles, and forming aggregates by mineral surface interactions. Thereby, PyOM can impact nutrient cycling and plant productivity, pollutant mobility, the soil microbiome, and edaphic fauna. These processes are of high importance for soil biochemistry, functioning, and carbon cycling but remain still largely unknown on the process- to field-scale. This is further related to the challenge of quantifying and measuring PyOM in complex soil matrices. To better understand the effects of PyOM on soils and affected ecosystems, a better knowledge of the abovementioned interlinked processes and novel methods are urgently needed.
This session aims to bring together monodisciplinary as well interdisciplinary research on PyOM-soil biogeochemistry. Early career researchers and underrepresented groups in the field are strongly encouraged to apply, including submissions from micro- to landscape scale experiments as well as modeling, or meta-analytical approaches and analytical developments.

Organic soils occur in a wide variety of wetlands (incl. peatlands) and play a crucial role in the global carbon cycle. Their extent and condition, however, is still uncertain due to their variety of abiotic and biotic features in a wide range of geomorphological settings globally, the invisibility of the peat layer itself with airborne mapping methods, manifold land uses applied, remote locations, lack of training data and diverse definitions (e.g. in relation to peatlands). These uncertainties extend if peaty soils (6-12% SOC) or shallow peat > 10cm come into focus (GPA 2022). Globally, peatlands in (sub-)tropical flooded savannas, mountains and along coasts are the most challenging to be mapped - where, at the small scale, organic and mineral soils are intertwining. The detection of organic soils under long term agricultural use and the translation of national and regional maps into local land use planning, bring along many challenges - particularly in the southern hemisphere.

In recent decades, the application of Digital Soil Mapping, Remote Sensing and GIS has come to the fore - to monitor, report and verify the spatial extent and condition of organic soils. Additionally, historic and legacy maps, as well as local knowledge, are increasingly acknowledged as ancillary sources, as well as the importance of dedicated field work highlighted. In this session we invite contributions from various scientific directions using established and innovative techniques to map organic soils at all scales to help resolving the uncertainties of their extent and status.

Grasslands cover about 40% of the Earth’s ice-free land surface, and their soils play a key role in climate regulation by storing about 20% of global carbon (C) stocks. These ecosystems are also characterised by their potential to sequester C as well as by emitting greenhouse gases (GHGs) such as CO2, N2O, and CH4. In recent decades, intensified grassland management has led to grassland deterioration, soil C loss, and increased GHG emissions. Reversing this trend presents significant opportunities for climate change mitigation, with the potential to sequester up to 150 Tg of soil C per year (CO2 eq) through effective management practices, such as improved grazing management or the introduction of silvopastoral systems (SPS). Additionally, promoting legumes or organic fertilisers can reduce reliance on synthetic N fertilisers, thereby mitigating the negative impacts of fertilisation. Realising this C sequestration and GHG mitigation potential requires collaborative efforts and a comprehensive understanding of the mechanisms driving these processes across diverse environmental conditions and grassland systems.
Despite the testing of various restoration strategies and improved management practices, there remains a significant gap in evidence regarding the mechanisms driving C sequestration potential and GHG mitigation globally.

This session will focus on studies that evaluate the impacts of different grassland restoration and management practices on soil nutrient C and N cycling, with an emphasis on soil C sequestration and GHG emission and mitigation. We encourage contributions from all regions, as diverse perspectives and experiences are crucial for a holistic understanding of these issues. Field and modelling studies are welcome, as well as mesocosm studies exploring hypotheses related to C and N cycling in grassland soils.

We invite participants from around the world to share their insights and contribute to a global dialogue on advancing grassland management practices.

Management practices such as reduced or no tillage, cover crops, and incorporating organic amendments, are increasingly implemented to sequester additional carbon in agricultural soils. However, the persistence and vulnerability of the freshly incorporated carbon remains unclear. Additionally, management practices that increase SOC may induce additional greenhouse gas (GHG) emissions, particularly nitrous oxide (N2O).
This session will assess the trade-offs between management practices aimed at increasing SOC sequestration in agricultural soils and GHG emissions, with the goal of achieving true climate-smart soil management. We invite contributions exploring trade-offs under different management practices, soil types, and climatic conditions, and assessing the mechanisms responsible for them. We are seeking contributions from all pedo-climatic zones, using both measurement and modeling approaches which quantify GHG fluxes and SOC stocks and their trade-offs.

Automated chamber systems are advancing our fundamental understanding of the biogenic greenhouse gas (GHG) fluxes, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), in terrestrial and aquatic ecosystems. Chamber based flux data is often used to derive emission factors for GHG accounting, for example for agricultural systems, which are central for climate mitigation actions.
New technologies are developing fast and produce large, high-frequency datasets consisting of thousands of flux measurements, enabling new insights into key biogeochemical cycles and their temporal and spatial regulation. However, the increased amount of data also creates a need for new methodologies for raw data processing, data curation, and data analysis to harness the complexity in these data sets. Examples of analytical challenges include: how to objectively quality control flux data? how to develop robust methods for selecting the appropriate time window for flux calculations during a chamber closure period? how to interpret large datasets? We seek abstracts on field and laboratory studies utilising automated systems for measuring surface-atmosphere GHG exchange, novel processing and analytical approaches for automated chamber data, and modelling studies based on automated chamber data.

Managed agricultural ecosystems (grassland and cropland) are an important source and/or sink for greenhouse gases (GHG) as well as for reactive trace gases. Representative measurements and modelling under typical conditions as well as for potential mitigation options are necessary as a basis for recommendations to policy makers and farmers.
Due to the simultaneous influence of various environmental drivers and management activities (e.g. fertilizer application, harvest, grazing) the flux patterns are often complex and difficult to attribute to individual drivers. Moreover, management related mitigation options may often result in trade-offs between different GHG or between emission of GHG and reactive gases like NH3, NOx, or VOCs. To investigate these interactions, the session addresses experimentalists and modelers working on carbon and nitrogen cycling processes and related fluxes on plot, field, landscape, and regional scale. It is open to a wide range of studies including the development and application of new devices, methods, and model approaches as well as field observations and process studies. Particularly welcome are studies on multiple gases and on the full carbon, nitrogen or GHG budgets. We also encourage contributions about the applicability and overall potential of mitigation options.

Methane (CH4) and nitrous oxide (N2O) are among the most important greenhouse gases (GHG) after carbon dioxide (CO2) in accelerating global warming and deserve special attention as their concentrations increase. Forest ecosystems play an important role in the exchange of GHGs with the atmosphere. It has been shown that not only soils but also trees play a significant role in the net exchange of CH4 and N2O in forests. Trees can contribute to ecosystem exchange by uptake and transport of soil-produced CH4 and N2O to the atmosphere, by in situ production and consumption of both gases in plant tissues, and by modifying carbon and nitrogen turnover in adjacent soils. However, the contribution of these individual processes to the net ecosystem GHG exchange is still unclear and appears to depend on many aspects such as tree species (tree traits), forest ecosystem type, environmental parameters and seasonal dynamics. Soil-tree-atmosphere interactions play a crucial role in controlling the global budget of these gases.

This session aims to bring together scientists working on CH4 and N2O cycles in forest ecosystems across different climatic and hydrological ranges and scales, which is crucial for improving our understanding of CH4 and N2O exchange in forest ecosystems. We welcome contributions on production and consumption processes and mechanisms in soils and plant tissues, as well as on gas transport processes in the soil-tree-atmosphere continuum. Gas flux measurements from forest soils, cryptogams, tree stems, leaves or canopies with chamber systems or integrated ecosystem approaches (flux tower with eddy covariance, satellite or modelling) would be highly appreciated. Methodological studies closely related to the investigation of CH4 and N2O exchange in forest ecosystems are also welcome.

Solicited author:
Prof. Daniel Epron (University of Kyoto, Japan)

The study of nitrogen (N) processes in soils has a long and distinguished history. Recent research efforts have targeted the direct quantification of N turnover in the soil plant atmosphere system across scales. Nevertheless, methodological constraints, the high spatial and temporal variability of soil N transformation, and the multitude of interacting factors determining N availability and loss from soils presents significant challenges that make accurate quantification difficult, thereby limiting our quantitative understanding of the N turnover.
Although the factors controlling N turnover in soils are relatively well established under laboratory conditions, transposing these relationships to the field and landscape scales remains a significant challenge. The absence of data-sets collected in-situ impedes the validation of N processes, such as mineralization and denitrification simulated via process-based models, thereby rendering their results at field and regional scales highly uncertain. However, current ecosystem management challenges require accurate predictions of N fate to enable sustainable management that minimizes environmental losses.

We invite contributions from the following fields:
• Methodological advances in measuring and modelling of soil N processes, spanning from the micro- to the landscape scale;
• Measurements of N fluxes including specific loss pathways under field or field-like conditions with a focus on identifying controlling factors;
• Comparative studies demonstrating/evaluating novel approaches to constrain N turnover such as incubation under He/O2 atmosphere, 15N-tracer technique, N2O isotopologue approaches or other innovative methods;
• Process-based modelling of soil N processes at various scales;
• Linking nitrogen transformation rates to the function and structure of the soil microbial community.

Soils and sediments are heterogeneous over space and time and across multiple scales. As a result, biogeochemical processes in soils are also heterogeneous over space and time. However, the degree to which small scale biogeochemical “anomalies” alter the fate of soil carbon, nutrients, and contaminants remains unknown. This session explores how heterogeneous soil processes and/or properties influence larger scale carbon, nutrient, and/or contaminant mobility. Topics may include (but are not limited to) how aggregate, moisture, rhizosphere, and redox dynamics ultimately influence 1) nutrient and contaminant behavior 2) greenhouse gas emissions 3) soil carbon storage and 4) mineral transformations. We welcome lab, field, or theoretical modelling-based studies spanning the nano-, micro-, meso-, and macro- scales as well as novel methodological insights that advance understanding of heterogeneous soil processes and their importance in biogeochemical cycles.

Climate change affects the dynamic feedbacks among plants, soil, and microbial communities, and thus strongly influences terrestrial biogeochemical cycling. In this session we address the question: What is the impact of changing environmental conditions on the plant-microbe-soil system, and what are the resulting effects on soil biogeochemistry? Given the positive and negative feedbacks with the climate system, dynamics of soil organic matter across terrestrial ecosystems are a key focus of this session.

We invite contributions from manipulative field experiments, observations in natural-climate gradients, and modeling studies that explore the climate change impacts on plant-soil interactions, biogeochemical cycling of C, N, P, microbial diversity and decomposition processes, and deep-soil biogeochemistry. Submissions that adopt novel approaches, e.g. molecular, isotopic, or synthesize outputs from large-scale, field experiments focusing on plant-soil-microbe feedbacks to warming, wetting, drying and thawing are very welcome.

This is the continuation of our 2023 and 2024 successful session on the same topic and focus. We would like to continue bringing people together with this session in order to learn from each other’s studies on soils and climate change from a global range of pedogenic and environmental settings.

Soil microbial communities are central regulators of carbon and nutrient cycling and thus strongly shape terrestrial ecosystems responses to climate change. It is therefore essential to study how microbial communities respond to diverse aspects of climate change, including gradual increases in temperature or atmospheric CO2 levels, as well as extreme weather events such as drying-rewetting cycles, heatwaves, or floods.
In this session, we invite empirical and theoretical studies that investigate the resistance, resilience, and adaptation of soil microbial community structure, activity, and function, in response to climatic disturbances. Studies on the response of multiple global change factors are particularly welcome. We also welcome research on the interactions between soil microorganisms, plants and fauna across temporal and spatial scales. We seek to establish a discussion platform to review the current state of the-art, identify knowledge gaps, exchange ideas, and address the emerging challenges of predicting the role of soil microbial communities in a changing world.

Minerals constitute the very building blocks of soils and control important soil functions such as water infiltration, contaminant immobilisation, nutrient provision, and carbon storage. They create habitats for soil organisms, modify soil pore spaces for gas and liquid transport through soil, and take part in numerous chemical reactions involving both organic and inorganic substances. In order to establish soils as part of the solutions for the abundant anthropogenic challenges, a thorough understanding of soil mineralogy, its dynamics in space and time, and of interactions between soil minerals with other soil components is critical. This session celebrates the fundamental contributions of soil mineralogy to our understanding of soil systems at multiple scales. We invite contributions that feature soil minerals as controls of matter and energy fluxes, their interaction with organic and inorganic soil nutrients and contaminants, and as controls of physical soil properties. Contributions addressing soil mineral transformations in dynamic environments are equally welcome. Our session offers a broad forum to discuss the most recent advances in exploring the diverse functions of soil minerals at any temporal or spatial scale and to address their responses to changing environmental conditions. This will help identify future directions for soil mineralogical research and strengthen the perspective of soil minerals as fundamental mediators of soil physical and (bio)chemical processes.

Stable isotopes are powerful tools for tracing water fluxes and associated nutrients in the soil-plant-atmosphere continuum. Given the complex interactions between subsurface water fluxes, plant water uptake and atmospheric drivers, new field- and laboratory-based methods should enable observations of ecohydrological processes at a high temporal and spatial resolution and with high precision and accuracy. At the same time, ecohydrological models shed new light on water and nutrient fluxes in the soil-plant-atmosphere continuum. We welcome experimental and modelling studies that present methodological developments and applications of isotope tracers to improve our process knowledge of water and nutrient fluxes between the subsurface, plants and the atmosphere, across different scales (from plant and forest stand up to the catchment scale). In our session, we aim to discuss i) innovative process-based interpretations from stable isotope data, ii) novel methods of model applications and data analysis, as well as iii) current methodological developments. We aim to foster interdisciplinary exchange between the various fields assessing ecohydrological processes using natural tracers, including research in groundwater and vadose zone hydrology, plant physiology, and ecology.

Peatlands develop in specific hydrological settings and are highly sensitive to changes in hydrological conditions and climate. For example, both peat hydrological properties and peatland greenhouse gas balance can change drastically after disturbances such as drainage, permafrost thaw, or mechanical compaction. Hydrological conditions are also a key control for a number of the ecosystem services offered or regulated by peatlands, including biodiversity, carbon storage, and nutrient retention. In addition, the role of pristine and disturbed peatlands in flood retention, support of low flows and regional climate remains debated. As hydrological and biotic processes in peatlands are strongly coupled, predicting the eco-hydrological effects of climate change, degradation, and restoration on peatland ecosystem responses—including greenhouse gas emissions—is a demanding task for the peatland community.

This session addresses peatland hydrology and its interaction with ecosystem processes in all latitudes. We especially encourage papers on permafrost and tropical peatlands for which field studies are scarce and inclusion into Earth system models is largely pending. We invite submissions on: (1) hydrological processes operating in all types of peatlands (pristine, disturbed, degraded, drained, managed, rehabilitated or re-wetted) in boreal, temperate, and tropical latitudes; and (2) the first-order control of peatland hydrology on all kinds of peatland functions.

We aim to advance the transfer of knowledge and methods and welcome laboratory, field, remote sensing, and modeling studies on hydrological, hydrochemical, biogeochemical, ecohydrological or geophysical topics, as well as ecosystem service assessments.

Tree rings are one of nature’s most versatile archives, providing insight into past environmental conditions at annual and intra-annual resolution and from local to global scales. Besides being valued proxies for historical climate, tree rings are also important indicators of plant physiological responses to changing environments and of long-term ecological processes. In this broad context we welcome contributions using one or more of the following approaches to either study the impact of environmental change on the growth and physiology of trees and forest ecosystems, or to assess and reconstruct past environmental change: (i) dendrochronological methods including studies based on tree-ring width, MXD or Blue Intensity, (ii) stable isotopes in tree rings and related plant compounds, (iii) dendrochemistry, (iv) quantitative wood anatomy, (v) ecophysiological data analyses, and (vi) mechanistic modeling, all across temporal and spatial scales.

The interaction between the soil-plant-atmosphere compartments and human activities is of paramount importance for the sustainable management and preservation of ecosystem functions and services. The functionality and services of terrestrial ecosystems are threatened by global climate change and human activities. The complexity and comprehensiveness of the impacts have so far proven challenging to assess due to the limitations of simplified experimental approaches and long-term observations, which often focus on a limited number of response variables.
Experimental systems such as lysimeters or ecotrons provide continuous, high-resolution and high-quality observations of detailed time series, which are crucial for a more accurate determination of the Earth's ecosystem services and functions and for promoting interdisciplinary ecosystem research.
This session will mainly focus on the diversity of ecosystem research using research platforms of lysimeters and ecotrons. We would also like to address the challenges of modelling ecosystem processes, comparison of metrics with other in situ instruments, upscaling approaches from such platforms to larger scales, validation studies (e.g. remote sensing), but also new developments in the field of lysimetry and further development of processing algorithms for interpretation of high temporal resolution lysimeter/ecotron weight data. We welcome contributions that (1) present novelties in the field of lysimeters, (2) assess and compare the functioning and services of terrestrial ecosystems, particularly in relation to climate change, (3) focus on water and nutrient transport processes (4) and greenhouse gases within the soil-plant-atmosphere continuum, (5) develop new techniques for the analysis of lysimeter and ecotron observations, (6) include ecosystem or hydrological modelling approaches using in situ observations from lysimeters or ecotrons.

Global glacial retreat is increasingly producing new ice-free areas in various geomorphological settings, from high-mountain valleys to coastal lowlands. The associated losses include decreased provision of meltwater in summer, decreased reflection and cooling, and in some cases increased natural hazards. However, there may be advantages, such as carbon storage in the vegetation, soil development and enlargement of pasture lands in now-exposed glacial sediments. An integrated, multi-disciplinary projection of the future properties and value of deglaciated and deglacierized valleys remains elusive but is necessary as we prepare for an uncertain future under climate change. Most existing research of these systems focuses on quantifying rates of individual processes in deglaciated valleys, mostly as a function of time since deglaciation in a space-for-time approach. Multidisciplinary studies are starting to explore interactions between pedological, ecological, chemical and geomorphic processes, and impacts of drivers other than time are being related to proglacial dynamics as well. Experimental work is starting to directly measure the impact of human interventions to increase functionality and productivity.
We warmly invite contributions of all these types of studies, particularly when they improve methodology, are multidisciplinary or from previously understudied mountain regions – including in the global south.

The session invites experimentalists and modelers working on air-land interactions from local to regional scales, in vegetated and/or urban systems. The program is open to a wide range of innovative studies in micrometeorology and related atmospheric and remote sensing disciplines. The topics may include the development of new observational devices, measurement techniques, experimental designs, data analysis methods, as well as novel findings on surface layer theory and parametrization, including local and non-local processes. Theory-based contributions may encompass soil-vegetation-atmosphere transport, internal boundary-layer theories, and flux footprint analyses. Of particular interest are synergistic studies employing experimental data, parametrizations, and models addressing energy and trace gas fluxes (of inert and reactive species) as well as water, carbon dioxide and other GHG fluxes. We focus on addressing outstanding problems in land surface boundary layer descriptions such as complex terrain, effects of horizontal heterogeneity on sub-meso-scale transport processes, energy balance closure, coupling/decoupling, stable stratification and night time fluxes, dynamic interactions with atmosphere, and plants (in canopy and above canopy) and soils.

The forest floor is the most reactive part of forest soils with much faster biogeochemical turnover than the mineral soil. Owing to its high reactivity and to its position as interface between the aboveground and belowground parts of the ecosystem, it is more responsive to climatic or management changes of forest ecosystems than the mineral soil. Currently, temperate European forests undergo significant changes, mainly induced by climate change, eutrophication, species composition and management. Negative consequences for forest floor functioning are documented, potentially impacting forest soils as a whole. Yet, forest floors are often not considered adequately and therefore, we are neither in a position to assess the current state of functioning or predict future developments, nor can we estimate consequences for mineral soils and forest ecosystem health.
With this session we encourage interdisciplinary exchange addressing the causal links between controls, properties, and functioning of forest floors. We aim to elucidate forest floor vulnerability to climate change and to identify biological, chemical, morphological and physical forest floor properties, serving as indicators for forest soil health. We encourage contributions that integrate multiple scientific disciplines and approaches to draw a holistic picture of forest floor functioning at different levels from micro, to soil profile to the landscape scale.

Coastal vegetated environments are among the most carbon-dense ecosystems on Earth and are often collectively referred to as Blue Carbon habitats. These habitats include salt marshes, mangrove forests, and seagrass meadows. They play a variety of important roles such as biodiversity support and coastal protection, while also providing nature-based solutions contributing to the mitigation of anthropogenic carbon dioxide emissions.

Coastal vegetated ecosystems are under increasing pressure globally due to climate and sea-level change, as well as local anthropogenic activities, which can disrupt their resilience and their carbon balance. There is a pressing need to understand and address these global change impacts and pressures upon carbon cycling in these ecosystems, as well as the disruption to their overall ecosystem dynamics. A better understanding of the feedback loops between sediment carbon and vegetation, the intricate exchanges of different forms of carbon between the atmosphere, sediment, and water, and the interplay between human activities, carbon and ecosystem dynamics are all priority areas for further research effort.

The purpose of this session is to foster a convergence of scientists from multiple disciplines, including biogeochemists, ecologists, geographers, geoscientists, social scientists, as well as environmental managers and those interested in blue carbon policy development.

The session welcomes studies that (i) advance our understanding of all processes related to plant biomass and soil carbon in blue carbon ecosystems under past, current, or future environmental conditions; and (ii) underscore examples of successful management, conservation, and restoration practices, particularly in the context of enhancing carbon sequestration, burial and long-term storage, and the delivery of ecosystem services.

This session will contribute to the United Nations Decade for Ocean Sciences, with co-convenorship by the UN Ocean Decade Programme for Blue Carbon in the Global Ocean (GO-BC).

BG4.4 | Session description

The coastal ocean has been increasingly recognized as a dynamic component of the global carbon budget. This session aims at fostering our understanding of the roles of coastal environments and of exchange processes, both natural or perturbed, along the terrestrial / coastal sea / open ocean continuum in global biogeochemical cycles. During the session recent advancements in the field of coastal and shelf biogeochemistry will be discussed. Contributions focusing on carbon and nutrient and all other element's cycles in coastal, shelf and shelf break environments, both pelagic and sedimentary, are invited.

This session is multidisciplinary and is open to observational, experimental, modelling and theoretical studies in order to promote the dialogue. The session will comprise subsections on coastal carbon storage, on benthic biogeochemical processes and on biological and ecological experimental approaches in marine biogeosciences.

Our ability to understand biogeochemical cycles of carbon, nitrogen and phosphorus and other elements in aquatic ecosystems has evolved enormously thanks to advancements in in situ sensor measurements, laboratory techniques and predictive models. The aim of this session is to demonstrate how this methodological advancement improves our understanding of coupled hydrological, biogeochemical and ecological processes in freshwater aquatic environments. In particular, our session focuses on improving the identification and quantification of the sources, delivery pathways, transformations and environmental fate of carbon and organic matter, nutrients, sediments and emerging contaminants in aquatic environments. We welcome presentations on applications of novel techniques to improve our understanding of aquatic environments and robust data-driven and modelling approaches for advanced processing of aquatic biogeochemical data. As hydrological, biogeochemical, and ecological processes undergo accelerated change, this session welcomes also studies presenting approaches and tools to monitor, model, and predict water quality and sensitivity of aquatic ecosystems to global change and human disturbance.

Redox sensitive elements (RSE) are typically found in higher concentrations in sediments from oxygen-depleted environments compared to their detrital levels. While modern ocean waters are generally well-oxygenated, oxygen-deprived settings are found in isolated basins and high-productivity zones. Historically, oxygen-depleted environments were more prevalent on early Earth. The degree of RSE enrichment in ancient sediments indicates the oxygen-poor conditions of the sedimentary environment. However, there is a need for more precise tools to describe ancient environments, necessitating extensive interdisciplinary research on the mechanisms of RSE accumulation in anoxic sediments. A comprehensive understanding of RSE behavior in anoxic settings requires detailed knowledge of the chemistry involved, not just in anoxic environments. This session presents new research on RSE using various techniques (mass spectrometry, isotopic analysis, elemental speciation, solid phase characterization, radiochemical methods) across different environments (lakes, rivers, ocean) with varying oxygen concentrations and penetration depths in the water column and sediments. We encourage contributions that employ interdisciplinary and multi-analytical approaches to describe RSE sedimentary phases, RSE speciation in aqueous phases, RSE cycling at the oxia/anoxia boundary, and overall research that advances understanding of the (bio)geochemistry of RSE.

To understand marine realms of the Earth and answer questions about biotic evolution and ecosystem functioning in the past, present and future, laboratory- or natural-based experimental approaches can contribute substantially. This includes experiments controlling environmental variables, using stable or radioactive isotopic biomarkers, breeding experiments, genetic analyses, biomineralization experiments of calcareous or siliceous organisms, experiments for proxy development, theoretical experiments up to modelling, machine learning and data analysis approaches or even natural laboratories (e.g., areas of biological invasion, vent and seep activities, tsunami landslides and turbidites, and many other natural situations strongly influencing the environment). Altogether, they decode faunal and ecosystem functional responses to changing connectivity patterns, habitat change or global change threats. These experimental approaches and their effective evaluation using various data analysis tools contribute greatly to a better understanding of how biotic evolution takes place in nature, how ecosystems also act as functional labs, and how Earth systems have moved and can move dynamically. They enable us to make more robust projections into the future or decipher past ecosystem trajectories with potential analogues to future change.

Our capacity to estimate regional and global budgets of greenhouse gases (GHG, including CO2, CH4 and N2O) from aquatic ecosystems has been significantly improved during the past decade, thanks to the substantial increase in field measurements. However, global estimates of these fluxes remain highly uncertain. Moreover, compared with terrestrial ecosystems, the field of aquatic GHG research is still young and the mechanisms behind the spatiotemporal patterns and variability of GHG concentrations and fluxes in aquatic ecosystems are not sufficiently understood, constraining model development. Therefore, to improve our estimations and understanding of regional and global GHG budgets from aquatic ecosystems, this session welcomes contributions on e.g.:
1) Field observations of GHG dynamics and fluxes in aquatic ecosystems, both freshwater and marine systems.
2) Experiments revealing physicochemical or biological processes or factors of relevance for GHG production, consumption, transport, emission, or uptake.
3) Model development or simulation efforts to estimate GHG dynamics and fluxes across different spatial and temporal scales along the aquatic continuum.
Contributions providing additional perspectives of relevance for aquatic GHG cycling and fluxes are also of interest.

Estuaries are transition zones between inland and coastal waters and thus form unique environments that are affected and modified by natural processes and often through human interventions. Tidally influenced estuaries experience great temporal variabilities in water level, salinity, and suspended particulate matter (SPM) dynamics. Changes in the amount and quality of the organic matter (OM) within the SPM also play a key role in estuarine hydro- and oxygen dynamics, e.g., through microbial degradation processes.
Human activities (e.g., shipping, fisheries, and land reclamation) highly affect estuaries, with interventions like dredging or the reduction of flood plains strongly influencing SPM dynamics and morphology. Also, estuaries are often polluted by nutrients and anthropogenic particles such as microplastics, which alter the biochemistry and have far-reaching ecological impacts. Biochemical processes, such as biofouling, can in turn modify the dynamical properties of particles and thereby influence the transport processes of fine sediments and anthropogenic particles.
This session focuses on the interplay between physical and biogeochemical processes in estuaries and welcomes contributions on the topics of SPM and fluid mud dynamics, particle dynamics (e.g., microplastics), oxygen dynamics, and biogeochemical and microbial processes, using different methodological approaches including, but not limited to, in situ or laboratory measurements, remote sensing or modeling. Interdisciplinary contributions that explore the connections between these different processes are particularly encouraged.

Wetland ecosystems provide essential services for the subsistence of life on Earth; however, these ecosystems face constant external threats that affect and change their natural processes and dynamics.

Significant knowledge gaps exist on multiple aspects, components, and interactions of wetlands worldwide. Multitemporal Earth observations offer an excellent opportunity to address these knowledge gaps and are sometimes the only source of information in remote and non-instrumented areas.

This session focuses on studies using Earth observation data (from passive and active sensors) to explore and understand wetland dynamics, processes, and services, as well as their broader connections with other elements of the landscape. It encompasses investigations into various components and processes of wetland ecosystems, such as (but not limited to) water dynamics, vegetation changes, disturbances, soil moisture, biodiversity, across a range of wetland types (e.g., marshes, swamps, fens, bogs, peatlands, lakes, ponds, coastal wetlands).

The session also encourages studies utilizing multi-sensor approaches, as well as machine learning, deep learning, and artificial intelligence technologies, to develop innovative solutions for wetland monitoring, conservation, and restoration.

The river-sea continuum concept offers a powerful framework for understanding the dynamic and interconnected nature of aquatic ecosystems, from headwaters to the ocean. Central to this concept is the role of organic matter and the microbial communities that drive its transformation and turnover across different stages of the continuum. This session seeks to explore the complex relationships between organic matter, microbial ecology, and their ecological roles throughout the river-sea continuum.
Organic matter, in its various forms, is a key driver of ecosystem processes, influencing nutrient cycling, energy flow, and the overall health and stability of aquatic environments. As main players in organic matter decomposition and transformation, microbial communities play a pivotal role in these processes. However, the specific mechanisms by which microbial communities interact with organic matter, and how these interactions vary along the river-sea continuum, remain topics of ongoing research and debate.
This session invites contributions that address the following themes:
• The sources, composition, and fate of organic matter along the river-sea continuum.
• The structure and function of microbial communities in relation to organic matter dynamics.
• The impact of environmental factors such as climate, hydrology, and human activity on the interactions between organic matter and microbial communities.
• The implications of these interactions for ecosystem functioning, resilience, and response to environmental change.

Natural organic matter (NOM) is the largest reservoir of reduced organic carbon on Earth, affecting C-N-P storage, metals availability, microbial activity, and the retention of organic contaminants, thereby modulating global biogeochemical cycles and processes. In seawater, NOM primarily exists in dissolved form as dissolved organic carbon (DOC), accounting approximately 662 Pg C, a value approximately equal to the atmospheric CO2 (750 Pg C). In terrestrial and atmospheric ecosystems, NOM accounts for around 1500 Pg C and 16 Tg C, respectively. Compositionally, NOM is a complex and heterogeneous mixture of thousands of organic substances with varying molecular sizes, physical and chemical properties, as well as a range of functional groups, including aromatic, aliphatic, phenolic and quinone structures. Currently <10% of NOM has been chemically characterized at the molecular level (as the sum lipids; amino acids and sugars) while, a plethora of molecular formulas in NOM isolated from various environmental compartments have been revealed from mass spectrometric techniques.
This session invites researchers with diverse expertise in spectroscopy (NMR, fluorescence, XPS) and mass spectrometry (Py-GC–MS; IR-MS, FTICR-MS; LC-MS-MS, FTMS; HR-MS) to present new findings and approaches on the composition and transformation of NOM including contaminants using the aforementioned techniques in the terrestrial, aquatic and atmospheric environment. We particularly welcome contributions that:
i) Introduce new methodologies and applications for HR-MS, FT-IRMS, and especially NMR—the latter, despite its potential, remains underexplored in environmental studies.
ii) Present innovative technologies for field study of NOM or monitoring of organic contaminants in the environment.
iii) Develop new practices for exploring, processing and storing biogeochemical data generated from spectroscopic and mass spectrometric techniques

Continental shelf sea sediments play a crucial role in the global carbon cycle due to their vast spatial extent, yet their relative importance in storing organic carbon remains a subject of much debate. Organic carbon storage in these sediments is highly spatially variable, driven by a complex interplay of physical, chemical, and biological processes. Despite advancements in the field of sedimentary Blue Carbon, knowledge gaps remain regarding spatial variability in organic carbon accumulation rates, long-term accumulation and burial, and the role of organic carbon source or reactivity in creating stocks in continental shelf sediments.

The proposed session aims to convene a diverse group of researchers to explore and discuss the factors influencing sedimentary Blue Carbon accumulation and storage across continental shelf seas, laying the foundation for discussions focused on marine management and conservation strategies. This session invites researchers working on:

(i) Processes that influence organic carbon accumulation, such as sedimentation rate and post-depositional degradation. We particularly welcome talks that address knowledge gaps regarding organic carbon burial and the link to biological processing and biodiversity.
(ii) The composition of stored organic carbon, including the differentiation between labile and refractory fractions, as well as the sources of organic carbon in continental shelf sediments.
(iii) The availability and spatial coverage of data supporting organic carbon stock assessments and estimates of transfer efficiency.
(iv) The mechanisms of organic carbon deposition are an important consideration, and we welcome discussion on how hydrodynamic conditions, such as tidal currents and wave action, as well as biological feeding and activity, affect the deposition of fine, organic carbon-rich, material on the seabed.
(v) The use of advanced techniques for mapping sedimentary Blue Carbon stocks, with an emphasis on the importance of remote sensing, modelling, and machine learning.

These discussions would complement a session focusing on the vulnerability of continental shelf organic carbon stocks to human disturbances. By integrating diverse perspectives, the session aims to enhance understanding of sedimentary Blue Carbon dynamics and inform policy and management strategies for carbon sequestration and climate change mitigation.

The ocean has stored vast amounts of carbon and heat due to anthropogenic CO2 emissions and climate change. We need to understand the processes driving this storage, that is uptake from the atmosphere, transfer to the ocean interior, redistribution within the ocean, and return to the ocean surface and the atmosphere. Also, ocean storage of carbon and heat are not independent: oceanic CO2 storage affects atmospheric CO2 levels, thereby atmospheric and oceanic warming. Ocean warming importantly, besides others changes ocean circulation and mixing which influences further uptake of both anthropogenic heat and carbon, and also perturbs the preindustrial ocean-atmosphere exchange of both, heat and carbon.

This session invites observational, numerical modeling and analytical studies that enhance the process understanding of ocean storage of carbon and/or heat under various climate scenarios: the contemporary situation of net-positive CO2 emissions and global warming, as well as future scenarios involving the gradual phasing out of CO2 emissions or a warming overshoot followed by net-negative emissions and global cooling. We also seek studies that explore the similarities and differences between ocean storage of carbon and heat, and how ocean uptake —and potential future release— affect climate.

Solicited author: Roland Séférian

Impacts of climate change are converging in Greenland fjords. The Greenland Ice Sheet (GrIS) is the second-largest mass of fresh ice on Earth and has been accelerating in mass loss since the late 1990s. This ice loss is causing an increase in freshwater discharge to the ocean, and glacier retreat is inflicting morphological changes to fjords which alter circulation patterns. Fjords, glacially carved channels, are a gateway between the the fresh GrIS meltwater run-off and the oceanic waters of the Greenland shelf. Fjord bathymetric and hydrographic conditions are greatly variable and set unique dynamics and ecosystem functioning for each fjord system. In addition, other environmental changes such as sea ice loss, and freshening and warming of coastal waters have the potential to alter the physical, biogeochemical and biological processes in fjords and coastal seas. However, the remote location of fjords and harsh weather conditions make research around Greenland difficult resulting in many unknowns about the environment and dynamics in these locations. The objective of this session is to assess the state of art of the oceanographic conditions and processes occurring in fjords and seas of Greenland from a physical, biogeochemical, and biological perspective. We invite observational and model studies with the following topics to apply: glacier-ocean interface; freshwater runoff; marine-biogeochemistry; marine biology; heat/freshwater content and fluxes; and ocean water mass dynamics.

Covering 70% of the Earth's surface, the sea surface microlayer (SML) is recognized as a critical boundary between the ocean and atmosphere. Its unique position places the SML at the center of various global processes in biogeochemistry and climate science. This session welcomes recent advancements in understanding the SML's distinctive chemical, biological, and physical characteristics, with a focus on understanding the underlying mechanisms of processes. Particular emphasis is given to the SML's function in modulating air-sea exchanges of heat, freshwater, gases, particles, and biota, but also exchange processes between the SML and the underlying bulk water, which are crucial for a more comprehensive understanding.. The concept of the SML as a biogeochemical reactor is also a central theme in the session to highlight the roles of environmental interfaces in marine biogeochemistry. Of further interest is the accumulation of pollutants such as hydrocarbons, microplastics, soot and pharmaceuticals, but also pathogenic microorganisms and viruses. In this context, the formation of (bio)aerosols as well as deposition processes play a role. To advance future studies, new observational, experimental and genomic approaches to the study of SML are particularly welcome. This multidisciplinary session welcomes participants from all research fields interested in the SML and its impact on surrounding environments. The session aims to bring together insights and findings from field observations, laboratory experiments, and models. By exploring the interplay between physical, chemical, and microbiological processes at the ocean-atmosphere interface, we seek to further develop a holistic perspective and foster new collaborations across research disciplines.

At the catchment scale, ecohydrology – an interdisciplinary field merging principles from ecology, hydrology, biology, and geomorphology – is crucial for understanding the interactions among energy, water, and carbon cycles that sustain and define the functioning of catchments. Key ecohydrological fluxes include plant (evapo)transpiration, primary productivity, and autotrophic and heterotrophic respiration. The “green” and “blue” components of a catchment, representing its terrestrial and riverine environments, respectively, play significant roles in shaping these fluxes. In terrestrial environments, above-ground vegetation and below-ground biomass are the primary contributors. In riverine environments, flowing water (blue water) is not only essential for nutrient transport but also for nutrient processing.
This session aims to highlight interdisciplinary ecohydrological research, focusing on (but not limited to): theoretical, numerical modeling and remote sensing that improve our understanding of water and carbon fluxes in catchments and their interactions. Contributions may span different climatic contexts, from small to large catchments, to highlight the relevance of both green and blue water in changing environments.

The ever-increasing demand for accurate and reliable oceanographic data has made advancements in ocean instrumentation systems crucial for understanding the complexities of marine environments. Ocean instrumentation systems are at the core of modern oceanographic research, enabling scientists to monitor, explore, and diagnose physical, chemical, and biological processes in oceans. However, these systems face significant challenges in deployment, maintenance, data accuracy, and long-term sustainability in harsh oceanic conditions.
Contributions from researchers, engineers, and industry leaders working on sensor design, real-time monitoring systems, and autonomous platforms such as AUVs (Autonomous Underwater Vehicles) and ROVs (Remotely Operated Vehicles) are encouraged. Additionally, the session will cover diagnostic techniques for ensuring the reliability and functionality of ocean instrumentation, addressing issues like sensor drift, biofouling, power limitations, and the impact of extreme environmental conditions.

Ocean-atmosphere chemical flux exchanges have significant impacts on global biogeochemistry and climate. This session focuses on new research in the following areas: air-sea fluxes of greenhouse gases (e.g., CO2, CH4, N2O), atmospheric deposition of nutrients (e.g., nitrogen, phosphorus, iron) and its impact on ocean biological systems, the influence of ocean emissions of reactive gases and aerosols on atmospheric chemistry and climate (e.g., dimethyl-sulfide (DMS), marine organic compounds, halogenated species), and on the important biogeochemistry-climate feedback loops in the ocean-atmosphere system as well as future changes in these fluxes in response to anthropogenic and climate stressors. The session has long-standing links to the Surface Ocean Lower Atmosphere Study (SOLAS; https://www.solas-int.org/) and GESAMP Working Group 38 on atmospheric input of chemicals to the ocean (http://www.gesamp.org/work/groups/38). We welcome submissions from all remit areas of these programs, and from a range of analysis approaches: field measurements, remote sensing, laboratory studies, and atmospheric and oceanic numerical models.

This year we particularly welcome contributions on the following specialist themes:
(a) greenhouse gas emissions and cycling from coastal zones, with particular focus on the impacts of nutrient and pollutant transport across the land-ocean continuum (e.g. via riverine input, glacier meltwater runoff, submarine groundwater discharge), as well as benthic-pelagic coupling for greenhouse gas budgets in regional and global scales; and
(b) the role of the Sea-Surface Microlayer (SML) as a biofilm environment and direct air-sea- interface, and its influence on deposition and emission fluxes of gases, aerosols, and particulates between the ocean and atmosphere.

Global temperature reconstructions of the Holocene indicate a warm period typically between 10-5 ka BP, the Holocene Thermal Maximum (HTM). During the HTM, temperatures across the Arctic region are estimated to have been 1-3 Celsius degrees warmer than present, sea-ice cover was reduced, and the Greenland Ice Sheet retreated beyond its present-day margin. Although not globally synchronous, the HTM is a particularly interesting period to investigate the impacts of a warming climate and a dwindling cryosphere on Arctic ecosystems. This session is organized by the PAGES working group ACME (Arctic Cryosphere Change and Coastal Marine Ecosystems). We welcome observational (proxy-based) and/or modeling studies offering new insights into the timing, magnitude and impacts of the Holocene Thermal Maximum on the Arctic region. Studies from marine as well as terrestrial settings are welcome, and we encourage multi-proxy studies as well as studies combining classical and emerging approaches (e.g. microfossils, stable isotopes, biomarkers, eDNA, proxy-model comparison).

Fossil skeletal remains (tests, shells, bones, teeth…) are crucial archives for reconstructing past climates, studying biogeochemical cycles and ecosystems using a variety of proxies based on geochemistry, mineralogy or morphometry. The use of mineralised tissues as environmental palaeoarchives is not straightforward. Both the metabolism and the ecology of the organism that produced them must be taken into account. Indeed, the growth of these tissues results from specific biomineralisation pathways, and is dynamic, responding to biological and environmental factors, which can complicate interpretations of information from these archives. Nevertheless, biomineralised tissues provide opportunities for high-resolution reconstruction of environmental or ecological parameters in the deep past. The dynamic growth of hard tissues can be used to reconstruct temporal variations in the environment or ecology of the organism throughout its life-time, down to the hourly scale. Furthermore, the cross-examination of associated organisms with different ecological strategies can provide insight on the variability of environmental parameters in their respective habitats or on their ecological relationships.
This session aims to bring together palaeontologists, biologists, geochemists and other users and developers of proxies from different fields. We welcome contributions aiming to develop or use skeletal hard parts as archives for environmental and ecological parameters. We want to highlight the variety of proxies that can be applied on mineralised tissues to answer palaeoenvironmental and palaeoecological questions throughout the Phanerozoic, including proxy studies of the fossil record and proposals for new proxies. We also aim to stimulate discussion of the strengths and weaknesses of the proxies, and the biases associated with biogenic mineralisation, which are key to provide informed interpretation of proxy data. We thus welcome studies of modern organisms, in their natural or artificial habitats, aiming to understand biomineralisation pathways and how various environmental and ecological parameters are recorded in mineralised tissues or highlight how specific biases could be addressed. Finally, we hope that this session will encourage novel scientific collaborations for multidisciplinary and multiproxy studies of hard tissues.

This session aims to bring together a diverse group of scientists who are interested in how life and planetary processes have co-evolved over geological time. This includes studies of how paleoenvironments have contributed to biological evolution and vice versa, linking fossil records to paleo-Earth processes and the influence of tectonic and magmatic processes on the evolution of life. As an inherently multi-disciplinary subject, we aspire to better understand the complex coupling of biogeochemical cycles and life, the links between mass extinctions and their causal geological events, how fossil records shed light on ecosystem drivers over deep time, and how tectono-geomorphic processes impact biodiversity patterns at global or local scales. We aim to understand our planet and its biosphere through both observation- and modelling-based studies. We also invite contributions on general exoplanet-life co-evolution.

This session is co-organized by COST Action CA23150 - pan-EUROpean BIoGeodynamics network (EUROBIG)

As the Earth's climate continues to change with anthropogenic forcing, rising temperatures and extreme hydrological events are impacting vegetation and soil, directly altering wildfire dynamics. Recent decades have witnessed large-scale human modifications of natural land cover, amplified rates of ecosystem changes, and an increase in the intensity, extent, and frequency of wildfires. Our understanding of the dynamics of vegetation and fire and their links with atmospheric and surface conditions is mainly derived from in-situ observations and remote sensing products which are limited to the past few decades. While historical records extend our knowledge, these only add a few centuries at most. Paleo-environmental proxy records provide insights into a wide range of interactions between land cover, wildfire and climate predating human land management and anthropogenic climate change. Documenting these interactions and inferring their drivers is of utmost importance for understanding ongoing and future changes in climate and continental ecosystems. Recent years have seen an increasing number of high-resolution and multi-proxy reconstructions of vegetation dynamics, land cover, and wildfire regimes as well as novel paleo-environmental proxies and improved analysis methods. Coupled with significant improvements in simulating ecosystem dynamics and land-atmosphere interactions, these advances allow fresh insights into spatio-temporal dynamics of ecosystems in response to climatic perturbations.

We invite contributions aimed at understanding land cover, vegetation, soil, sub-surface, and wildfire dynamics from present-day, through the Quaternary into deep time, and their interactions with climate on seasonal to orbital timescales. These include: (a) regional and global-scale reconstructions of vegetation cover and composition from paleo-environmental data, (b) the development and application of innovative proxies and archives, (c) Earth system model simulations, (d) studies combining data and models, and (e) proxy system modeling and novel statistical methods to constrain vegetation and wildfire dynamics and their drivers. We also welcome contributions related to technical and analytical advancements in organic and inorganic chemical analyses, and in-situ calibration studies. Special attention is given to studies focusing on understudied regions and time intervals, and research that has the potential to inform future land management policies.

Speleothems are key terrestrial archives of regional to global paleoclimatic and paleoenvironmental changes on sub-seasonal to orbital scales. They provide high temporally resolved records which can be accurately and precisely dated using a variety of proxies such as stable O and C isotopes and trace elements. Recent efforts have seen the rise in more non-traditional proxies such as fluid inclusion water isotopes, organic biomarkers, pollen, dead carbon fraction etc.. This advancement towards quantitative reconstructions of past precipitation, temperature, or other environmental variables and climate patterns, are key variables for data-model comparisons and evaluation. Beyond this, caves and karst areas additionally host an enormous suite of other valuable archives such as cave ice, cryogenic carbonates, clastic sediments, tufa, or travertine sequences which complement the terrestrial palaeorecord, and are often associated with important fossils or archaeological findings.
This session aims to integrate recent developments in the field, and invites submissions from a broad range of cave- and karst-related studies from orbital to sub-seasonal timescales.
In particular we welcome contributions from:
(1) (quantitative) reconstructions of past climatic and environmental variables to reconstruct precipitation, vegetation, fire frequency, temperature etc. across different climate zones,
(2) field- and lab-based developments of process-based methods to improve our application of proxy variables,
(3) process and proxy-system model studies as well as integrated research developing and using databases such as SISAL (Speleothem Isotope Synthesis and AnaLysis).
We further welcome advancements in related and/or interdisciplinary areas, which pave the way towards robust (quantitative) interpretations of proxy time series, improve the understanding of proxy-relevant processes, or enable regional-to-global and seasonal-to-orbital scale analyses of the relationships between proxies and environmental parameters. In addition, research contributing to current international co-ordinated activities, such as the PAGES working group on Speleothem Isotopes Synthesis and AnaLysis (SISAL) and others are welcome.

Sedimentary archives can be found across diverse environments worldwide, allowing investigation and disentanglement of past environmental processes over different setting. However, one key limitation in the investigation of such records is deciphering the complexity of how the different forcings acting in a natural system are manifested in the environment and consequently propagated into the studied archives. Interpretations derived from any sedimentary archive thus depend on a our understanding of the surrounding natural system itself and its web of feedbacks, the investigated sedimentary record, and the utilized proxies. Such interpretations often call for the integration of different disciplines, the development of new tools for sampling, novel laboratory methodologies and modelling.

For this session we welcome any contribution that integrates sedimentological, geochemical, biological, and geochronological methods, as well as modelling approaches, novel laboratory experiments and monitoring, for the interpretation of sedimentary systems, with a special focus on mechanism-oriented interpretation. Contributions that either focus on the development and calibration of novel proxies, analytical approaches (either destructive or non-destructive) and data analysis (statistics, machine learning, AI), or present interesting case studies, are welcome as well.

Minerals are formed in great diversity under Earth surface conditions, as skeletons, microbialites, speleothems, or authigenic cements, and they preserve a wealth of geochemical, biological, mineralogical, and isotopic information, providing valuable archives of past environmental conditions. Interpretion of these archives requires fundamental understanding of fluid-rock interaction processes, but also insights from the geological record.

In this session we welcome oral and poster presentations from a wide range of research of topics, including process-oriented studies in modern systems, the ancient rock record, experiments, computer simulations, and high-resolution microscopy and spectroscopy techniques. We intend to reach a wide community of researchers sharing the common goal of improving our understanding of the fundamental processes underlying mineral formation, which is essential to read our Earth’s geological archive.

Micropaleontological data, such as assemblage composition, morphology, and evolutionary patterns, provide unique insights into the dynamics and tipping points of past environments and climate through changes in the fossil record. Micropaleontology lies at the heart of biostratigraphy and provides a fundamental tool for reconstructing and stratigraphically constraining past changes in the Earth system. Our session aims to gather a broad spectrum of micropaleontologists to showcase recent advances in applying micropaleontological data in paleoenvironmental, paleoclimatological, and stratigraphic research in both marine and terrestrial settings.
We invite contributions from the field of micropaleontology that focus on the development and application of microfossils (including, but not limited to, coccolithophores, diatoms, dinoflagellates, foraminifera, ostracods, radiolarians, pollen) as proxies for paleoenvironmental and paleoclimatological reconstructions and tools for stratigraphic correlation. We particularly encourage the submission of multi-proxy approaches, merging micropaleontological information with geochemical and paleobiological information. The application of microfossils as stratigraphic markers and advancing multivariate statistical techniques with a focus on microfossil assemblages is encouraged.

The Quaternary Period (last 2.6 million years) is characterized by frequent and abrupt climate swings and rapid environmental change. Studying these changes requires accurate and precise dating methods that can be effectively applied to environmental archives. Different methods or a combination of various dating techniques can be used depending on the archive, time range, and research question. Varve counting and dendrochronology allow for the construction of high-resolution chronologies. In contrast, radiometric methods (radiocarbon, cosmogenic in-situ, U-Th) and luminescence dating provide independent anchors for chronologies that span longer timescales. We particularly welcome contributions that aim to (1) reduce, quantify, and express dating uncertainties in any dating method, including high-resolution radiocarbon approaches; (2) use established geochronological methods to answer new questions; (3) use new methods to address longstanding issues, or; (4) combine different chronometric techniques for improved results, including the analysis of chronological datasets with novel methods, e.g., Bayesian age-depth modeling. Applications may aim to understand long-term landscape evolution, quantify rates of geomorphological processes, or provide chronologies for records of climate change and anthropogenic effects on Earth's system.

The geological record provides insight into how climate processes operate and evolve in response to different than modern boundary conditions and forcings. Understanding deep-time climate evolution is paramount to progressing on understanding fundamental questions of Earth System feedbacks and sensitivity to perturbations, such as the behaviour of the climate system and carbon cycle under elevated atmospheric CO2 levels—relative to the Quaternary—, or the existence of climatic tipping points and thresholds. In recent years, geochemical techniques and Earth System Models complexity have been greatly improved and several international projects on deep-time climates (DeepMIP, MioMIP, PlioMIP) have been initiated, helping to bridge the gap between palaeoclimate modelling and data communities. This session invites work on deep-time climate, Earth System model simulations and proxy-based reconstructions from the Cambrian to the Pliocene. We especially encourage submissions featuring palaeoenvironmental reconstructions, palaeoclimate and carbon cycle modelling, and the integration of CO2 and (hydro)climate proxies and models of any complexity.

Environmental DNA (eDNA) metabarcoding is a noninvasive method to detect biodiversity in a variety of environments that has many exciting applications for geosciences. In this short course, we introduce eDNA metabarcoding to a geoscience audience and present potential research applications.

This session aims to explore innovative methodologies for assessing soil fauna and ecosystem functionality, integrating both molecular and classical approaches. Next-Generation sequencing has allowed integration of techniques such as DNA metabarcoding and environmental DNA (eDNA) has revolutionised our understanding of soil ecosystems, allowing for unprecedented insights into microbial and faunal communities. The synergy between Sanger Sequencing, Next Generation Sequencing (NGS) and traditional classification methods can offer a comprehensive and more reliable view of soil biodiversity, enhancing our understanding of soil fauna, their roles and interactions. This session invites researchers to present and discuss novel methodologies, the associated challenges, and the integration of these techniques into broader biogeoscientific research. Through case studies and theoretical frameworks, this session will foster discussions on the pivotal role of molecular methods in advancing our understanding of soil biodiversity while emphasising the continued importance of traditional approaches.

Methane production and consumption have long been attributed to a narrow range of environmental conditions and a handful of microbial groups. Studies in recent years have however broadened our view, and have shown many novel microbes and redox processes to be involved in methanotrophy and methanogenesis. Advanced molecular methods have revealed new metabolic pathways and new archaeal and bacterial groups involved in methane production or methane oxidation. Isotope labelling studies and visualisation techniques have helped to identify syntrophic relationships and coupled redox pathways in complex communities.

In this session we invite studies addressing methane biogeochemistry and microbiology, including redox chemistry and molecular ecology. This includes for example studies regarding electron transfer mechanisms, thermodynamics, or the coupled cycling of methane and other compounds such as nitrogen, sulfur, iron or organic compounds. But also microbiome focussed studies are welcomed, such as studies on novel microbes related to methane cycling, syntrophic relationships, and novel metabolic pathways discovered in methanotrophic or methanogenic organisms. We welcome studies from all kinds of geographical locations and environments, including lake, marine, wetland, soil and permafrost environments.

Archaea, belonging to the domain of prokaryotes, are a crucial component of the tree of life. They are ubiquitous in contemporary surface and near-surface environments, playing a vital role in maintaining Earth's ecological functions and mediating biogeochemical cycles. They are also considered one of the earliest forms of life and recognized as a significant force driving the development of the early Earth's biosphere. However, like bacteria, archaea have left few fossil records in ancient strata, limiting research on their evolution during Earth's early history and their role in geochemical cycles. This session aims to explore the feasibility of studying the co-evolution of archaea and the earth system by leveraging large-scale, high-completeness archaeal genome data, in conjunction with known major geological events (such as the Great Oxidation Event, Snowball Earth, and the formation and breakup of supercontinents) and biogeochemical modeling. Researchers from both earth and life sciences are welcome to contribute to this session.

Microcosmic understandings of prevalence, interaction, toxicity, and transmission of Endocrine Disrupting Chemicals (EDCs) and microbes are crucial for advancing environmental health research. This session seeks contributions that delve into innovative methodologies, advanced sensing technologies, and integrated approaches to study the dynamics of EDCs and microbial contaminants at micro-scale levels. Topics include:
• Utilization of cutting-edge sensor technologies (e.g., microfluidics, biosensors) for real-time detection and quantification.
• Integration of molecular techniques, spectroscopic analysis, and modeling to assess toxicity and interactions in environmental matrices.
• Case studies highlighting successful applications of microcosmic research in understanding contamination pathways and informing mitigation strategies.
• Challenges such as sensitivity limits, analytical methods validation, and data interpretation in micro-scale environmental studies.
This session aims to foster collaborative discussions among researchers, practitioners, and policymakers across disciplines like environmental chemistry, microbiology, and toxicology to address emerging challenges and explore future directions in understanding and managing microcosmic contaminant dynamics.

This session is dedicated to discovering environmental DNA (eDNA), organic matter (OM), and community structures of, for example, diatoms or other microbes as innovative tools to trace water and sediment transport within and across landscapes and ecosystems. These new techniques bring cutting-edge approaches in biology to hydrological process research. We explore the methodologies, applications, and implications of their integration.

Presentations within this session will center on understanding and characterizing the movement of biological tracers within hydrological systems, considering factors such as their distribution, degradation characteristics, transport mechanisms, and interactions with environmental parameters. Moreover, this session will showcase advancements in laboratory techniques and modeling approaches tailored to simulate the transport dynamics of biological tracers in hydrological systems. Presentations will highlight accuracy, resolution, and complexity improvements, fostering discussions to enhance our predictive capabilities and understanding of tracer behavior. Influential variables such as water flow, sediment dynamics, temperature, and nutrient availability will be explored. Key processes to be addressed include tracer deposition, uptake, and transformation, shedding light on their role in shaping hydrological processes and ecosystem functioning.

While we’ll primarily focus on DNA analysis, carbon tracing techniques, and diatom characterization, we also welcome contributions employing additional approaches such as modeling and theoretical concepts. We look forward to your contributions that explore the intersection of biology and hydrology, which we hope will pave the way for interdisciplinary collaborations and breakthroughs in environmental science.

Soil microorganisms are the principal actors in key soil functions, including nutrient cycling, carbon transformation, and clean water provision. Their growth and anabolism rely on C and energy as well as various nutrients (e.g., N and P) in appropriate stoichiometric relationships. Various sources of organic matter fulfill these needs, which are transformed into new cellular growth, microbial storage compounds, microbial products or greenhouse gases such as CO2. Microbial death processes close the loop to return biomass to non-living soil organic matter as necromass, with altered properties. Theoretical and experimental approaches are providing new insights into this coupled, dynamic system and the diverse communities that drive it. This session integrates experimental and modelling insights to elucidate the energy and matter flows driven by soil microbial metabolism, their dependency on environmental conditions, and the implications for soil functioning.

We welcome submissions seeking to understand how, when and where soil microorganisms transform organic matter through their metabolism, growth and death. Topics of interest include characterization of microbial activity and turnover using advanced methods (e.g., isotope tracing, calorimetry, metagenomics), microbial ecophysiology and stoichiometry, carbon and energy-use efficiency, alongside approaches to understand microbial functional responses (e.g. dynamic modelling, artificial intelligence). We aim to stimulate interdisciplinary discussions to advance our understanding of soil biology at scales from the mechanistic understanding of biogeochemical processes to global change.

We are excited to have Stefano Manzoni (Stockholm University) as an invited speaker for the session.

Soil food webs are incredibly diverse, from viruses to rodents, arthropods and plant roots, but are too rarely approached in their entirety and many studies focus instead on a single group of interest. Soil food webs also largely determine soil biogeochemistry, yet numerous studies treat them as a "black box" when considering the effects of e.g. warming or increased snow depth. Therefore soil food webs and their biogeochemical impacts remain poorly understood, particularly so in remote areas such as the Arctic. Moreover, Arctic soils and the fate of their enormous carbon and nitrogen stocks are a major uncertainty in our understanding of biogeochemical cycles in a warmer world. Drivers such as glaciations and complex biogeographical history have deeply affected soil food webs across the Arctic, and continue to have profound impacts on soil functioning and biogeochemistry.

We aim to gather studies linking descriptive approaches of the soil food web with their biogeochemical impacts, not only in the Arctic but also in other cold environments characterized by glaciation history and strong biogeographical limitations, i.e. the Antarctic and glacier forefronts in alpine regions. We expect that putting together cross-taxa and interdisciplinary approaches to the soil food web and its biogeochemical impacts across analogue ecosystems will lead to stimulating discussions and perhaps to the discovery of common patterns in the establishment and functionality of soil food webs in post-glacial environments.

Across our planet, microorganisms - including bacteria, archaea, viruses, microalgae, and fungi - play vital roles in nutrient cycling and ecological balance. Airborne microbial cells that were emitted from marine and terrestrial surfaces are transported and redistributed in the atmosphere on various temporal and spatial scales.
While extensive research has been dedicated to understand microbial communities in the cryo-, litho-, hydro-, and phyllo-spheres, studies on atmospheric microorganisms have been limited to describing their abundance, diversity, and potential climatic and sanitary implications. However, the atmosphere hosts living cells that take part in and are affected by biological, chemical, and physical processes while airborne, contributing to the intricate web of life on our planet.
The continuous exchange of microorganisms between surface habitats and the air makes the atmosphere an important, highly dynamic component of the microbial life cycle that effects biogeochemical cycles and chemical composition.
Thus, to gain a more complete understanding of the planet’s microbiome, it is important to identify atmospheric chemical, physical and biological factors that shape and modulate airborne microbial populations, diversity, and functioning. Such factors include, e.g., emission/deposition and transport processes, exposure to stress factors (e.g., oxidative or osmotic stress) and other intrinsic biological traits of airborne microorganisms which may contribute to their survival and activity.
This session will provide an interdisciplinary platform for atmospheric scientists, biogeoscientists, microbial ecologists and other researchers which are concerned with (i) the transport processes of living microorganisms, (ii) microbial processes in the atmosphere and their feedbacks on the Earth surface (water, soil, vegetation, ice), and (iii) atmospheric factors, processes and conditions that affect atmospheric microbial diversity, concentrations, survival, and functioning. We particularly encourage contributions that lead to a more comprehensive characterization of the microbiome and its interactions with the atmosphere and Earth’ surfaces.

Methane is of utmost importance as a trace gas in the atmosphere and we know that most of the environmental methane is produced - and also consumed in sediments and the water column of marine and lacustrine systems.
But…, understanding methane dynamics in the aquatic realm is still a major scientific challenge because it is governed by a vast diversity of geological, oceanographic/limnological, biological factors and anthropogenic causes.
In this session we will discuss controls on methane dynamics in marine and freshwater systems at present, in the geological past, and in future scenarios. Within this overarching theme we welcome contributions related to the following topics:

- methane formation: from water-rock interactions to petroleum systems and microbial methanogenesis
- methane transport: from subsurface fluid flow to bubble and diffusive transport mechanisms and fluxes.
- methane seepage and mud volcanoes
- anthropogenic factors: from hydrocarbon exploitation to energy infrastructure and hydraulic structures
- methane sinks: from microbes, biogeochemical pathways and kinetics to physicochemical processes and gas hydrate formation
- timescales: variations on diel, seasonal, and geological time scales
- methane-derived carbonates, microbe-mineral interactions, and molecular/micro/macro fossils
- methane releases in the geological past, consequences and climate change

The Earth’s magnetic field is produced by dynamo action in the liquid iron core, which has profound influence on our habitable planet. One of the most striking manifestations of the geodynamo are complete reversals of the dipole. Numerical simulations indicate that the lower mantle has a manifold impact on the dynamo whereby the absolute value and pattern of the heat flux through the core-mantle boundary affects the field strength, field geometry and reversal rate. However, neither the structure and the long-term evolution of the lower mantle and the core, nor the coupling between the two, are well understood. Moreover, field strength and reversal rate likely influence the survival and evolution of magnetoreceptive organisms, especially magnetotatic bacteria. We invite contributions that aim at understanding the long-term evolution of the geomagnetic field and Earth's core dynamics, deep mantle dynamics and its influence on the geodynamo. This interdisciplinary session aims to bring together paleomagnetists, seismologists, dynamo modellers, mantle dynamicists, mineral physicists, and biologists.

Shallow upwelling of the upper mantle is a key process in plate tectonics, allowing seafloor spreading, and enabling the formation of the ocean crust by decompression melting. Normally, the upper mantle is inaccessible beneath the crustal layer, so we rely on exposure along major faults, where dredge and submersible samples, and IODP drilling enables study of this important layer in the Earth.
IODP Expedition 399, in 2023, set a new record for drilling to depth of more than 1.2 km into upper mantle lithologies at the Atlantis Massif, 800 metres north of the Lost City vent field. Recovering mostly serpentinised depleted harzburgites, with dunite veins and gabbroic intrusions this hole provides new insights into the magmatic, hydrothermal and tectonic evolution of the upper mantle along slow-spreading ridges.. We expect this session to showcase initial results from Expedition 399, as well as providing an opportunity for comparison with other locations, particularly from near-ridge environments.
We encourage contributions from scientists working on abyssal peridotites including previous IODP holes, and on the chemistry of peridotite-hosted hydrothermal systems. Topics could include (1) the mechanisms for exhumation of mantle rocks, including deformation processes; (2) partial melting and melt transport in the upwelling mantle, and the relationship to crustal melts and gabbroic intrusions; (3) alteration of peridotites and gabbros during exhumation, including mineral alteration mechanisms and kinetics, and the impact of fluid-rock interaction on vent fluid chemistry, rheology and rock mechanics; (4) the diversity and extent of the shallow and deep biosphere associated with fluid-rock interaction in the exposed upper mantle.

The first half of Earth’s history (Hadean to Paleoproterozoic) laid the foundations for the planet we know today. But how and why it differed and how and why it evolved remain enduring questions.
In this session, we encourage the presentation of new approaches that improve our understanding on the formation, structure, and evolution of the early Earth ranging from the mantle and lithosphere to the atmosphere, oceans and biosphere, and interactions between these reservoirs.
This session aims to bring together scientists from a large range of disciplines to provide an interdisciplinary and comprehensive overview of the field. This includes, but is not limited to, fields such as early mantle dynamics, the formation, evolution and destruction of the early crust and lithosphere, early surface environments and the evolution of the early biosphere, mineral deposits, and how possible tectonic regimes impacted across the early Earth system.

This session examines serpentinization processes across various geological settings, from Earth's deep ocean floors to the surfaces of extraterrestrial bodies. We seek contributions that: (i) explore the role of serpentinite-hosted hydrothermal systems in the origin of life, focusing on early Earth conditions, such as hydrothermal vents and hyperalkaline springs, where the unique chemistry of serpentinites may have fostered prebiotic chemistry and the emergence of primitive life forms; (ii) aim to understand the physical properties of serpentinites, such as their rheology and magnetism, and how these properties influence mechanical and tectonic processes, including subduction dynamics in forearcs, mantle wedge hydration, fluid flow mechanisms, and the interplay between serpentinization and hydrothermal activity at mid-ocean ridges and continental-ocean transitions; (iii) investigate the role of serpentinites in Earth’s volatile geochemical cycles, from mid-ocean ridges to subduction processes, examining the role of fore-arc serpentinization, high-pressure devolatilization in volatile cycling, and redox processes, and their implications for arc volcanism and deep-Earth volatile recycling; (iv) explore the roles of serpentinites in hydrogen production across environments, including low-temperature serpentinization and its role in hydrogen production, crucial for sustaining microbial life, and the generation of geologic hydrogen as a potential energy source and its societal impact; (v) consider the broader implications of serpentinization on other planetary bodies, where similar processes might occur, potentially supporting life beyond Earth.

Contributions from various fields, including geodynamics, geochemistry, biochemistry, and geology, are welcome, incorporating theoretical, experimental, and natural examples. We encourage studies that address the intersection of serpentinization with broader planetary and astrobiological contexts, providing insights into the feedback mechanisms between serpentinization, hydrothermal budgets, and geological evolution in both terrestrial and extraterrestrial environments.

Massive volcanism, particularly from Large Igneous Provinces (LIPs), is generally thought to have triggered significant disruptions in surface climate, environmental conditions and biological evolution and extinction throughout Earth’s history. While the effects of volcanic volatiles have been extensively studied, the impact of subsequent weathering of large amount of volcanic rocks (e.g. continental and submarine flood basalt) on surface elemental cycling, climate fluctuations, and biological evolution remains less understood, particularly also regarding the timescales involved in these processes.
This session is open to studies exploring the effect of (both modern and past) volcanic rock weathering on atmospheric CO2 concentration changes, cycling of metal elements, climatic and environmental perturbations, the evolution or extinction of terrestrial and marine organisms, etc. Topics include, but are not limited to, proxy calibration in modern or diagenetic systems, experimental constraints, Earth system modelling, data-model calibrations, big data machine learning and novel proxy applications in the ancient sedimentary record. We especially encourage submissions with new and innovative insights regarding mechanisms, feedbacks, or quantitative thresholds driving the weathering of volcanic rocks and its relationship with environmental, climatic, and biological evolution.

Natural and human-induced disturbances are increasingly transforming terrestrial ecosystems through land cover changes, extreme climate events, and environmental pollution. These factors are accelerating globally, leading to a widespread decline in ecosystem services, loss of biodiversity, and disruptions in ecosystem functioning. Among the most critical consequences of anthropogenic climate change are the rising frequency and intensity of extreme climate events, such as droughts, heatwaves, wildfires, heavy rainfall, and windstorms. For instance, wildfires can severely impact ecosystem services like soil fertility, erosion control, and pollination, while drought episodes can disrupt ecosystem functioning, with cascading effects on various regulating and provisioning services. Although numerous studies have explored the effects of individual climate extremes at landscape scales, there remains a significant gap in understanding how these events interact with other drivers, such as land-use change and climate warming. This session seeks contributions that aim to: i) Enhance our knowledge of how climate extremes, in combination with other global change drivers like land-use change and climate warming, impact ecosystem services and biodiversity. ii) Identify methods to mitigate the decline in ecosystem services and functioning caused by climate extremes. iii) Address research gaps in understanding the full feedback loops between biodiversity loss, changes in ecosystem services, and climate extremes. iv) Explore strategies to mitigate the impacts of climate extremes, strengthen ecosystem resilience, and enhance ecosystem services.
This session also emphasizes the importance of implementing innovative policy tools and nature-based climate solutions that can improve biodiversity and, in turn, bolster ecosystem services. By addressing these critical issues, we can better inform policy decisions and deepen our understanding of biodiversity’s role in buffering against environmental changes.

Nature-based climate solutions, such as conservation agriculture, forest restoration, and wetland rewetting, offer great promises to increase soil organic carbon (SOC) and reduce greenhouse gas (GHG) emissions for climate change mitigation. However, they also impact a variety of ecosystem properties such as surface albedo, energy partitioning, and hydrological cycles. To effectively measure, report, and verify (MRV) SOC changes, GHG fluxes, and climate-relevant parameters or processes, enhanced monitoring and modeling capabilities are urgently needed to comprehensively quantify the dynamics of carbon, energy, water, and nutrients in ecosystems. This session welcomes a wide range of contributions on topics related to nature-based climate solutions in agriculture, forestry, wetland, and other landscapes including, but not limited to: (1) developing scalable and cost-effective monitoring capacities through proximal and remote sensing combined with modeling to track SOC changes, GHG emissions, surface albedo, energy and water fluxes; (2) synthesizing multi-source observations to infer changes in the mentioned parameters and processes in natural and managed ecosystems; (3) developing process-based models to simulate the coupled carbon-food-water-energy processes in various landscapes; and (4) Enhancing systematic model-data integration to quantify the climatic impacts of nature-based solutions and inform decision-making in farming practice, policy design, and economic returns.

As the name suggests, Nature-based Solutions are natural responses to challenges including climate change, water security or emergency risk management (such as flooding).
Unsurprisingly, Nature-based solutions come in many shapes and sizes, from protecting or restoring existing ecosystems to innovative hybrid approaches. For example, a revitalised wetland area may create a valuable carbon store and flood defence, while a new city park or green roof can contribute to urban cooling and benefit mental and physical health.
We would like to hear from those of you studying the implementation of Nature-based Solutions, in particular:
• Methodologies for implementing landscape scale studies
• Lessons learned when studying Nature-based Solutions
• Studies observing the relationships between carbon and biodiversity in these landscapes
• Discussions on how we scale up studies to landscape scale
An aim of this session is to encourage discussion between many disciplines, to get a greater understanding of the current work and evidence gaps in this rapidly evolving space

In recent periods, carbon sequestration by forests has attracted much interest as a mitigation approach and as a valuable nature-based option to address climate change mitigation challenges, to protect forest ecosystems, and to support socioeconomic and environmental services. The technological advancements and the constant focus of the scientific community have boosted the implementation of forest management practices that support the multiple functions of various forest types, soil and biodiversity conservation, the prevention of major disturbances (large droughts, wildfires, impacts of hurricanes, heavy snowfalls and floods, etc.) and the increase of forest carbon stock capacity in the short-, medium-, and even to long-term. This session aims to contribute to a better understanding and to shed light on the forests’ capacities to mitigate climate change, bringing together the latest advances from multi- and interdisciplinary studies (e.g. advanced ICTs, modeling, climatology, hydrology, soil science, or ecology), while considering the broad range of other forest values and ecosystem services in the context of bioeconomy and rural development. We invite forest scientists and experts working in other related disciplines, such as climatology, biophysical, and socio-economic modeling, to share their findings within this session, and improve the science-based knowledge on the environmental benefits, the social acceptability and the economic value of forest-based mitigation actions.

Transitioning our food systems to become more sustainable requires a quantitative and integrative understanding linking agricultural practices and impacts. A further requirement is a capacity to monitor the performance of farms in achieving sustainability objectives, encompassing environmental, economic, and social aspects. Depending on how such monitoring programmes are designed, they can be useful for policy makers, agricultural associations & retailers, and/or farmers themselves.

In this session, we invite contributions that focus on sustainability assessments within the agricultural sector. The methods and results used can either take all sustainability dimensions into account or focus on one sustainability dimension or even a single indicator (e.g. nitrogen surpluses, greenhouse gas emissions). To specify, we accept contributions focusing on the economic or social dimension alone if the used framework tackles sustainability as a whole (e.g. improving an animal welfare indicator in a sustainability tool). Studies using satellite data are welcome as long as the remote sensing product has a direct link to sustainability. Contributions may focus on pixels to parcels, from farms to landscapes, and from regions to continents.

A transformation towards sustainable agriculture is essential to secure food for both current and future generations while restoring natural resources. Agricultural productivity today faces multiple challenges, including climate change, water scarcity, limited access to essential inputs, socio-economic disparities, and rising global demand for agricultural products. Additionally, agriculture must play a pivotal role in mitigating climate change, reducing environmental pollution, and preserving biodiversity. Addressing these complex demands necessitates a comprehensive evaluation of alternative land management practices across local to global scales, with a focus on assessing entire agricultural production systems rather than isolated products.
This session will address the modeling of agricultural systems in the context of global change, focusing on challenges related to climate change adaptation and mitigation, sustainable intensification, and the environmental impacts of agricultural production. We invite contributions on methodological approaches, data innovations, assessments of climate impacts and adaptation strategies, environmental consequences, greenhouse gas mitigation, and economic evaluations.

Long-Term Flux Observation and Ecosystem Research Networks - Benefits for Science and Society

Distributed continental and global scale research infrastructures have fundamentally changed the environmental and ecological research landscape. They help forming new scientific collaborations and institutionalise existing ones, also across science disciplines and between data collectors and users. The net-working is supported by stakeholders at various scales and motivated by their various expectations -ultimately, the products’ usefulness for society. Since monitoring ideally extends indefinitely into the future, a challenge for contributing scientific institutes is to earn a sustainable funding and support by proving to be relevant to these goals. This relationship poses a communication challenge and this session offers a platform for communication across the whole scientific community including stakeholders.

We encourage contributions that
- present new developments and discussions from within the network community, for example with respect to standardization and co-location of measurements
- demonstrate unique and novel results that were made possible from the supports from the networks, and
- describe and assess the relevance of products from these networks for stakeholders and the society in general.

In this session, we aim at cultivating a scientific and personal dialogue between the heterogeneous parts of this growing scientific community. We invite participants, users and stakeholders of the networks to contribute to this dialogue and learn from other perspectives and experiences for the benefits of further developing this new and growing culture of scientific collaboration.

While the initiative originates from within the Integrated Carbon Observation System (ICOS), we particularly welcome contributions from other networks that relate their work to biogeochemistry research.

Direct flux measurements of heat, water, greenhouse gasses (GHGs) and pollutants between the earth’s surface and its atmosphere unlock fair and equitable climate solutions across natural and built environments. Innovations and markets based on such an approach help resolve global climate and air quality challenges and fairly reward small and big stakeholders.

This session, organized collaboratively by research and industry, welcomes ideas and examples of how to utilize direct flux measurements for tangible societal benefits, such as carbon removal, agriculture and forestry, reduction of anthropogenic emissions, environmental impact management, and more. For instance, these measurements can be applied to irrigation scheduling, soil and plant treatments, GHG reduction and sequestration, global warming potential, urban heat management, satellite and model products, industry emissions, severe weather impacts, air quality management, and can be used as a diagnostic tool for meeting net-zero targets by different organizations, regulatory, and government agencies.

Join us to discuss together developing a global paradigm for maximum-integrity, low-latency and economically sound earth stewardship, anchored in direct flux measurements.

In addition to rapid emission reductions, swift and large-scale carbon dioxide removal (CDR) is needed to reduce the risks of severe climate change. Multiple CDR approaches will be needed to deliver the targeted amounts of 10s of Gt CO2 yr-1. This session solicits multidisciplinary and novel contributions of research on two CDR approaches: enhanced rock weathering (ERW) and inland water alkalinity enhancement (IWAE), including: 1) technical aspects, 2) ecosystem impacts, both negative and positive, 3) best practices, 4) community engagement, 5) techno-economic and life cycle aspects, and 6) monitoring, reporting and verification approaches. Both ERW and IWAE aim to drawdown CO2 and convert it to bicarbonate for eventual delivery to oceans via rivers for long-term storage. This session thus aims to inform decision making on how and whether ERW and IWAE can be used to help us reach our climate targets.

By mid-century, the removal of several billion tonnes of CO2 annually will be required to meet the 1.5 °C target set by the Paris Agreement. This necessity underscores the importance of large-scale implementation of negative emission technologies (NETs) for carbon dioxide removal (CDR). As enhanced rock weathering (ERW) operations expand globally, the improved understanding of relevant mechanistic processes and the development of robust methods for MRV is crucial for achieving our climate goals. This session invites innovative research contributions on ERW, including: 1) recent developments in monitoring, reporting, and verification methods; 2) environmental and ecological impacts; 3) public engagement and perception; 4) strategies for scaling up ERW; 5) economic assessments; and 6) identification of knowledge gaps in the field. The session aims to showcase the latest research on technological innovations, practical applications, and limitations of ERW, while fostering cross-disciplinary collaboration to enhance its effectiveness as a CDR strategy for climate change mitigation.

Enhanced Weathering (EW) is a promising nature-based solution for atmospheric carbon removal, with estimates suggesting it has the potential to sequester gigatons of CO₂ per year. However, key uncertainties persist across the entire EW process, from the dissolution kinetics of silicate rock powder in soils to the transport and fate of weathering products in freshwater and marine environments. This session invites abstracts that address these uncertainties through theoretical, modeling, field studies, and experimental work. We particularly encourage cross-disciplinary contributions that explore not only the carbon sequestration potential of EW but also its co-benefits and environmental risks. By fostering collaboration across research disciplines and sectors, this session aims to advance a comprehensive understanding of EW, ensuring its scalable, safe, and effective role in global climate mitigation efforts.

Peatlands play a significant role in regulating the Earth’s climate system, storing around 30 % of global soil organic carbon. Carbon release due to peatland drainage and degradation contributes around 4 % to global anthropogenic greenhouse gas emissions. These peatland carbon emissions can be an important component of national GHG budgets.
Recent efforts, such as the EU nature restoration law, aim to restore and rewet drained peatlands to reduce GHG emissions, sequester atmospheric CO2, and improve ecosystem services. Large-scale implementation of restoration and management measures requires accurate accounting of emission balances, both to assess their effectiveness, and to incorporate them into potential carbon credit and monitoring, reporting, and verification (MRV) schemes.
There are several challenges associated with accurate accounting of GHG balances in peatlands: 1) lack of higher tier methods, particularly for restoration or alternative management methods such as paludiculture; 2) lack of effective methods for monitoring; 3) accounting for GHG emissions during transition periods after land use change; 4) accounting for trade-offs between CO2, CH4, and N2O emissions at different time scales; 5) emissions and management under future climate scenarios; 6) accounting for land use change related to infrastructure development. In addition, solutions to are still lacking to incorporate possible failure of rewetting projects and the considered time horizons into frameworks for carbon farming.

This session welcomes contributions on peatland systems globally that address aspects of GHG accounting and MRV schemes, including methodological development, field measurements, remote sensing, mapping of organic soils, hydrological, modelling, as well as interdisciplinary studies. Examples of regional and international standards for the voluntary carbon market are appreciated, as well as studies analysing the economic aspects of peatland rewetting.

Soil organic matter (SOM) plays a vital role not only in soil fertility and quality (by providing a number of physical, chemical, and biological benefits), but also in carbon cycling. SOM contains a vast range of diverse organic structures, and also a living component (microorganisms) with various residence times that define the central role SOM plays in the soil. The decline of SOM represents one of the most serious threats facing many arable lands of the world. One of the efficient approaches to increase SOM content and decrease land degradation is the application of organic amendments, such as crop residues and animal manures. Nowadays, organic amendments originate from many kinds of organic wastes, which are being increasingly produced mainly by farms, agro-food industries, municipalities, and energy plants. Besides serving as a source of organic matter and plant nutrients, these materials may contribute to reduce soil contamination, erosion, and desertification, as well as mitigate climate change. At the same time, a safe and useful application of organic amendments requires an in-depth scientific knowledge of their nature and impacts on the SOM pools and factions, soil-plant system, as well as on the surrounding environment.
This session will combine the current research and recent advances on the use of organic amendments in modern agriculture as well as for the restoration of degraded soils. Special attention will be given to the soil chemical, physical, biological and biochemical aspects. Field and laboratory studies focused on the effects of management practices, climate change, environmental conditions, soil properties are highly welcome.

Nature-based Carbon Dioxide Removal (CDR) technologies are a vital component in the fight against climate change. As emphasized by the IPCC, large-scale CDR will be essential to achieving the goal of limiting global warming to 1.5°C, especially in offsetting emissions from sectors that are difficult to decarbonize. Nature-based solutions such as reforestation, soil carbon sequestration, and blue carbon ecosystems offer not only a means of removing CO2 but also deliver multiple co-benefits, including biodiversity enhancement, ecosystem restoration, and community resilience.

In addition to their carbon sequestration potential, nature-based CDR initiatives can be integrated into sustainable business models rooted in the principles of the circular economy. These models promote regeneration, restoration, and sustainable resource management, creating value while ensuring ecosystems remain resilient and productive. The co-benefits of these strategies extend beyond carbon capture, supporting ecosystems through improved soil health, water retention, biodiversity conservation, and sustainable land-use practices.

We invite contributions focusing on technical innovations for the sustainable implementation of nature-based climate solutions capable of removing carbon dioxide from the atmosphere at a gigaton scale. We welcome case studies demonstrating how these implementations have progressed from Monitoring, Reporting, and Verification (MRV) to the voluntary Carbon Removal Market. Additionally, we encourage submissions exploring the integration of circular economy principles with CDR, as well as research assessing the co-benefits of CDR on ecosystem restoration, biodiversity protection, and broader environmental and social impacts. Join us in exploring how advancing nature-based CDR technologies can create a more sustainable, regenerative future while delivering significant climate benefits.

Global coastal zones are of high ecological and societal values. As the dynamic interface between land, sea, and air, they are heavily impacted by a combination of climate-driven environmental change and human interventions. Approaches to sustainably manage the coastal zone increasingly seek to provide co-benefits of risk mitigation, climate regulation, preserving biodiversity, and supporting coastal community resilience. These require scientific evidence and discourse that integrates across disciplines.

This session invites multi- and inter-disciplinary contributions focusing on coastal processes, their dynamic interactions, and their role in exchanges across coastal interfaces (e.g. land-sea, air-sea, …) under a changing climate and changing human activities. We welcome observational, modelling and theoretical studies reporting on processes linked to coastal hydrodynamics, coastal biogeochemistry, coastal ecology, or coastal sediment dynamics and geomorphology. Studies may span the wide range of spatial and temporal scales characteristic of existing and projected change in coastal seascapes and landscapes from the inner shelf shoreward to beaches and dunes, estuaries, intertidal flats, saltmarshes and coastal wetlands. We encourage the submission of holistic Earth system studies that explore the role of the coastal zone for coastal seas’ dynamics including exchanges across coastal interfaces (e.g. land-sea, air-sea, …) under the impact of climate change and human activities. We also encourage studies that focus on impacts of coastal management approaches on coastal processes and dynamics, spanning engineered, hybrid, and nature-based options related to changing activities such as coastal protection, tourism, shipping, fisheries and aquaculture, and the expansion of renewable energies and other coastal infrastructure.

As the endpoint of the biological carbon pump, the burial of sedimentary carbon in the seafloor represents the ultimate carbon sink in the earth system. In coastal, shelf, slope or deep ocean environments, these reservoirs can act as considerable long-term stores of carbon and as such are globally significant in climate regulation. However, marine sediments are under increasing global pressure from anthropogenic activities and from climate forcing itself, altering carbon reactivity, alkalinity generation, and overall burial efficiency.

Human impacts include, but are not limited to: bottom-contacting fisheries, marine aggregate mining, offshore construction such as offshore wind or tidal power developments or decommissioning, material dumping, and coastal protection. Such activities can modify sedimentary carbon storage through direct disturbance of the seafloor or indirectly by changing carbon supply, physical fields and/or ecosystem functions, including biological assemblage changes. Impacts of climate forcing may manifest in multiple ways, such as changes in riverine carbon export, marine production and temperature driven changes in carbon degradation, as well as increased sediment remobilisation caused by changes in metocean conditions. Although the magnitudes of these impacts, their connection to the global carbon cycle, and implications for marine spatial management strategies have recently been discussed intensively, a consensus has yet to be achieved on the net effects on key carbon parameters and budgets. The goal of this session is to promote this debate on the way to achieve scientific consensus about the vulnerability of sedimentary carbon sequestration to human disturbances across multiple temporal and spatial scales.

In this multidisciplinary session we invite all experimental, observational and modelling studies related to human impacts and climate forcing on subtidal sediments. We especially encourage contributions which seek to resolve interactions between human activities, climate forcing, sediment transport, marine biota and the carbon cycle to inform management and policy questions.

Achieving the climate goals of the Paris Agreement requires deep greenhouse gas emissions reductions towards a net-zero world. Advancements in mitigation-relevant science continuously inform the strategies and measures that society pursues to achieve this goal. This session aims to further our understanding of the science surrounding the achievement of net-zero emissions and the Paris Agreement mitigation goal with particular interest in remaining carbon budgets, emission pathways entailing net-zero targets, carbon dioxide removal strategies, the theoretical underpinnings of these concepts, and their policy implications. We invite contributions that use a variety of tools, including fully coupled Earth System Models (ESMs), Integrated Assessment Models (IAMs), or simple climate model emulators.

We welcome studies exploring all aspects of climate change in response to ambitious mitigation scenarios, including scenarios that pursue net negative emissions and a reversal of global warming. In addition to studies exploring the remaining carbon budget and the transient climate response to cumulative emissions of CO2 (TCRE), we welcome contributions on the zero emissions commitment (ZEC), effects of different forcings and feedbacks (e.g. permafrost carbon feedback), non-CO2 contributions to stringent climate change mitigation (e.g. non-CO2 greenhouse gases, and aerosols), and climate and carbon-cycle effects of carbon removal strategies. Interdisciplinary contributions from the fields of climate policy and economics focused on applications of carbon budgets, net-zero pathways, and their wider implications are also encouraged.

This session examines the environmental impacts and opportunities arising from the global shift to renewable energy systems (RES), including solar, wind, and smart, decentralized energy solutions. As these systems expand, they bring significant shifts in land use and ecosystem dynamics, which pose challenges and opportunities for biodiversity conservation, ecosystem services, and long-term sustainability.
We invite research that examines:
• The environmental effects, trade-offs, and co-benefits of RES, particularly their impacts on hosting ecosystems (e.g., grasslands, arid environments, aquatic ecosystems) and human-made landscapes (e.g., arable land).
• Strategies for conserving biodiversity and enhancing ecological outcomes during the transition to renewable energy systems, including sustainable land use and land management approaches.
• Opportunities provided by RES to improve environmental co-benefits, such as promoting ecosystem services and maximizing techno-ecological synergies that enhance the sustainability of these systems.
• Methodological approaches, including remote sensing, modeling, and empirical field studies, to better understand and manage the impacts of energy transitions on ecosystems.
• The role of RES in promoting long-term sustainability through strategies that integrate technological innovation and ecological preservation.
We encourage abstracts based on empirical evidence, modeling, or framework-based approaches that propose solutions for the sustainable integration of renewable energy systems within local and regional environments.

Biogeomorphology explores the complex feedbacks between life and landscapes, seeking to understand how geomorphic processes govern, and are governed by, biological processes. Uniting our understanding of biotic and abiotic systems and processes remains challenging, due in part to the complexity of the systems being studied, but also due to the interdisciplinarity of biogeomorphology, which draws insights, methods and theory from across a range of scientific domains. Understanding the interplay between biotic and abiotic processes, at continental to hillslope scales, is critical to our understanding of landscape and ecosystem function, sediment transport dynamics, landscape restoration and rewilding, hazard mitigation and landscape evolution modelling. The urgency with which we study these processes is also heightened by the increasing intensity of the climate crisis, with rewilding and landscape restoration increasingly being advanced as options to mitigate climate impacts.



This session aims to bridge the disciplinary divide between geoscientists, ecologists, soil scientists, engineers and geomorphologists, bringing together researchers and practitioners to share expertise and insights from their work across a range of domains and contexts. We welcome submissions exploring a broad range of landscape and ecosystem settings at scales ranging from catchment to continent and from single species to multi-species studies. Topics may include, but are not limited to: novel numerical, computational, field or laboratory methods; case studies of biogeomorphology applications; quantification and monitoring of biogeomorphic processes; feedbacks between biotic and abiotic systems; hazard management and landscape and ecosystem management approaches. We particularly encourage the participation of early-career researchers and PhD students working in these fields, as we aim to grow the network of researchers working on this topic across disciplines.

The United Nations has designated the 2020s as the decade of ecosystem restoration. In addition to existing regulations from the Water Framework Directive, the EU has recently adopted a nature restoration regulation aiming to restore 20% of EUs degraded ecosystems by 2030. Restoration of streams, rivers and their catchments is particularly important, as these are amongst the most threatened habitats globally, impacted by a cascade of pressures, including direct modification, catchment landuse, and climate change. Furthermore, restoration of riverscapes and their catchments are becoming increasingly important to dampen the effects of altered hydroclimatic regimes, yet more challenging to restore a moving target with altered flow and sediment regimes and habitat conditions. Our scientific understanding of riverscape restoration is challenged by the complexity and interdisciplinary nature of river processes and the lack of long-term, large-scale monitoring. In this session we wish to highlight a broad range of research that moves our understanding of riverscape management forward, in particular novel studies focusing on building river resilience to a changing climate. We also encourage submissions focused on any aspect of river management from different disciplines, including geomorphology, hydrology, and ecology. We hope to initiate discussion among an interdisciplinary group of researchers of how to take into account a changing climatic baseline in future river restoration and evaluation of restoration success.

Soil pollution is a global threat that seriously affects biodiversity in (agro)ecosystems and compromises the quality of food and water. Besides naturally elevated levels of potentially toxic elements and compounds, most contaminants originate from human activities such as industrial processes and mining, poor waste management, unsustainable farming practices and accidents. One of the most important issues in pollution research is the assessment and evaluation of pollution, including assessment and evaluation of the distribution of pollutants in soils, mobility, chemical speciation, as well as evaluation of the probability of soil-plant transfer and accumulation in plants.
This session aims to bring together contributions of all aspects of biogeochemical research related to soil pollution risk assessment, including (but not limited to) assessment of pollution status, geochemical mapping, analysis of element cycling within soils and ecosystems, as well as ecotoxicological considerations.
We warmly welcome presentations of laboratory and field research results as well as theoretical studies. Our aim is to create a community of scientists from multiple disciplines. Young researchers are especially encouraged to submit their contributions.

Practical implementation of Soil Health Legislation. Implementing the practical aspects of Soil Monitoring Laws requires the combination of Practical, Scientific and Economic solutions for the robust monitoring of land under different use over time. Optimization of a number of approaches across fields from repositories, indicators to logistics and methodologies will be required for reliable metrics and continuous enhancement of monitoring practices.

This session aims to advance knowledge transfer in soil science through evidence synthesis methodologies and results. Research papers accumulate, and piles of original data and legacy data are reused to test and verify hypotheses and try to solve a vast array of issues scientifically. Evidence synthesis is the process of collecting, evaluating, and integrating multiple pieces of research, data or information to build a comprehensive understanding of a specific issue, or research question. Our objective is to provide a more robust and complete view of the evidence available. The synthesis of evidence is crucial in soil science and provides a benefit for everyone when it comes into the hands of policy stakeholders and decision-makers. The most renewed approaches to evidence synthesis include Systematic reviews and Meta-analyses. The latter type of analysis is sometimes inappropriately used for studies that do not use statistical techniques correctly to combine the results of multiple studies to estimate the overall effect of an intervention or phenomenon.
We invite contributions on the following topics: Systematic reviews and meta-analyses in soil science,
Novel approaches to evidence synthesis in agro-environmental science, Case studies demonstrating the impact of evidence synthesis, and the role of evidence synthesis in addressing global soil challenges.
The expected outcomes of this session are to strengthen networking opportunities for participants to collaborate on future projects. This session is part of the broader framework of the soil system science division and aligns with EGU’s mission to promote geosciences and foster interdisciplinary collaboration. By focusing on evidence synthesis and education in soil science, we aim to address critical aspects of knowledge transfer and societal impact.

Agriculture is pivotal in the European economy and the global food supply. Europe is a significant producer of diverse crops, contributing significantly to feeding the world's population. The quality and characteristics of agricultural products are closely linked to the specific environmental conditions in which they are grown. These environmental factors, including climate, soil, and water, can vary significantly across regions and are increasingly influenced by the challenges of climate change.
Understanding the spatial and temporal variability of environmental factors is crucial for managing and preserving agricultural landscapes and adapting to climate change's current and future impacts.
This requires a deep understanding of plants’ mechanisms for acclimation, keeping in mind that functional traits (e.g., phenology,etc.) can be indicators and proxies of plant status, plasticity and resilience. Moreover, it involves applied research and technological innovation in agriculture, including the use of sensors to monitor environmental variables, remote sensing and drones for crop monitoring, predictive models for yield and disease, and advanced methods to study nutrient cycles and soil health.
Furthermore, growing public awareness of the importance of ecosystem health and sustainability has led to adopting quantitative approaches to understand the link between agricultural practices and ecosystem services, which are crucial for achieving long-term environmental goals. Agroecological approaches, such as cover cropping, organic amendments, and integrated pest management, are being increasingly adopted to enhance biodiversity, soil health, water and nutrient retention, and resilience to climate change.
On these bases, the session will delve into:
- Quantifying and Spatially Modeling Environmental Factors: Examining the complex interplay of climate, soil, and water and their influence on plant growth, yield, and quality.
- Agricultural Resilience to Climate Change: Exploring the adaptability of agricultural systems in the face of a changing climate and identifying strategies for adaptation and mitigation.
- Sustainable Agricultural Practices and Ecosystem Services: Analyzing the impact of diverse agricultural practices on soil and water quality, biodiversity, and related ecosystem services.
- Precision Agriculture and Technological Innovation: Utilizing advanced technologies to optimize resource use, improve crop management, and enhance sustainability.

The present context of accelerated changes in both climate and land use imposes an unprecedent pressure on a number of vulnerable ecosystems including wetlands, forests and rangelands, in which vegetation closely interacts and coevolves with soils and landforms. Complex interactions between climate, soils and biotic factors are involved in the development of landform-soil-vegetation feedbacks and play an important role in making ecosystems resilient to disturbances. In addition, large shifts in the distribution of vegetation and soils are associated with losses of ecosystem services (including carbon capture), frequently involving thresholds of ecosystem stability and nonlinear responses to both human and climatic pressures. This session will focus on ecogeomorphological and ecohydrological aspects of landscapes (including their connectivity), conservation of soil resources, and the restoration of ecosystem services and functions. We welcome theoretical, modelling, and empirical studies addressing the distribution of vegetation and coevolving soils and landforms, and particularly, contributions with a wide appreciation of the soil erosion-vegetation relationships that rule the formation of landscape-level spatial organization. We also welcome studies describing the implications of these spatial patterns of soils and vegetation for the resilience and stability of ecosystems under the pressure of climate change and/or human disturbances.

Soils represent a major terrestrial store of both organic and inorganic carbon. At present soils are a net carbon sink, and building soil carbon stocks holds a potential to contribute to achieving net zero carbon. Furthermore, the accrual, stability, and cycling of carbon is fundamental to the productivity and resilience of soil systems, and preserving or even increasing soil carbon stocks is critical for allowing sustainable agricultural crop production.

Avenues for organic carbon sequestration in soils include plant-based inputs, the addition of pyrogenic carbon (biochar), and addition of composts or other additives such as manures and soil conditioners provided additionality and leakage effects are considered. Enhanced silicate weathering may hold significant potential for building up inorganic carbon stocks, while inputs from bedrock, and mediation by land use changes such as afforestation, may also increase inorganic soil carbon stocks.

This session seeks to explore how soil carbon stocks can be increased so as to simultaneously enhance agricultural productivity, mitigate negative repercussions of changing environmental conditions, and contribute to achieving carbon neutrality. Alongside this, advances in methods for monitoring and modelling rates of soil carbon loss or carbon sequestration in soils are key to inform political, agronomical, and geo-engineering approaches. We welcome contributions exploring methods of increasing both organic and inorganic carbon stocks, and studies exploring the storage, stability, and cycling of carbon within soil systems. Early career researchers are strongly encouraged to apply, and we seek submissions considering empirical, modelling, or meta-analytical approaches.

Soil biota and their ecosystem services as main drivers of soil sustainability still need to come more into focus in both society (awareness) and science (understanding processes and interactions). Moreover, monitoring of soil biodiversity is needed to track long term impacts of land use and climate change on soil health mediated by soil biota.
Although land use and agricultural production heavily relies on multiple processes driven by soil organisms, soil biodiversity has rarely been considered when shaping farming systems and European agricultural policy. At the same time, there is growing awareness worldwide that soil health and biodiversity are interdependent and that reductions in soil biodiversity make soils more vulnerable to degradation processes (IPBES 2018, FAO and OECD 2018). The Sustainable Development Goal number 2 calls for implementing agriculture practices that improve resilience and health of soils to ensure sustainable food production systems by 2030. In order to find solutions for increasing soil sustainability and resilience across Europe, the scientific discussions on agricultural management, its impact and use on soil biota to improve soil status and health are essential. This session aims to focus on soil biota (1) as provider of services and key actors to get towards sustainable systems in land use with high self-regulating power, (2) on supporting and detracting practices of land use on soil biota to enable valuation of systems in terms of their soil biodiversity impact and (3) on methods and tools to improve soil biodiversity monitoring.

Modern agriculture has led to the degradation of inherent soil organic matter (SOM) and release of CO2 into the atmosphere. Contrastingly, in recent years it has been proposed that there is a potential not only to reduce agricultural CO2 emissions but also to transform farms into carbon capturing systems, contributing to climate mitigation. Carbon farming (i.e., SOM accrual through agriculture), is an attractive solution, as it has many agronomic advantages and can potentially contribute to crop resilience towards climate change. But, is carbon farming for climate mitigation a plausible reality or just fantasy? Despite years of research, there are still open questions regarding carbon farming such as: How will climate change impact SOM accrual achieved by carbon farming? Is there a limit to SOM storage in soil? How to quantify SOM changes and indices of its stability in agricultural systems? What is the scale of compensation? Are carbon credits a viable solution? These questions point to gaps in our understanding of SOM dynamics and its transformation to agricultural practice and policy.
In this session, we aim to raise the discussion on carbon farming and promote knowledge interchange towards enhancement of SOM accrual. We invite contributions that focus on agricultural systems including experimental studies on novel agro-technical strategies to accrue SOM, crop and soil biome modifications for enhanced SOM accrual, advances in methods to estimate SOM stocks, research on SOM dynamics as well as life cycle analysis, meta-analysis and modelling. For this matter, we relate to all farming systems, including field crops, orchards, greenhouses and grazing systems. Moreover, critical approaches on carbon farming and climate justice are invited.

Soils are one of the largest terrestrial sinks for organic carbon, and therefore present a promising opportunity to mitigate climate change. Over the past decade, many global initiatives have been launched to enhance soils’ capacity to sequester and store organic carbon. A noteworthy example is the ‘4 per mille’ scheme, launched at the Paris Climate Change Conference in 2015. This initiative proposed that annual CO2 emissions from fossil fuel burning could be offset if the global stock of soil organic carbon was increased annually at the rate of 4 parts per 1000. Eight years have elapsed since this initiative was launched, and a debate ensues about the extent to which soils have the capacity to endlessly increase their carbon storage. In this session, we will showcase research that interrogates both arguments of the ‘carbon saturation threshold’ debate. Is there a threshold above which a soil profile can no longer increase its carbon storage? If so, what is this threshold, and what are the implications for both land management and our Net Zero Carbon targets? What are the mechanisms determining differences between soils’ soil carbon saturation thresholds, and over what timescales may saturation limit the capacity of soils to mitigate climate change? We welcome empirical work, model-based efforts, or desk-based reviews. Early career researchers are strongly encouraged to apply.

Accurate and precise, long-term measurements of greenhouse gas (GHG) concentrations were an original cause for concern linking human activities to rapid, and so far, unceasing rise in global GHG concentrations. The resulting increases in global temperatures, sea-level, glacial retreat, and other negative impacts are clear. In response to this evidence, nations, states, and cities, industries and individuals have been accelerating GHG emission reduction and other mitigation efforts while working towards equitable development and environmental justice. Research advances have shown that GHG measurements and analyses are much more than merely harbingers of global warming. The urgency, complexity, and economic implications of the needed GHG emission reductions and other climate action demand strategic investment in science-based information for planning, implementing, and tracking emission reduction policies and actions. Several national and international efforts seek to enhance the capacity of nations, states, cities, and industries to target emissions reduction opportunities and track progress towards their goals. Success depends on the availability of measurements of atmospheric composition, GHG fluxes, and emission activity data in key GHG emission source regions and relies on a multi-tiered observing strategy involving satellite, aircraft, and surface-based measurements, as well as innovative data mining and analysis methods.

Since EGU18, this session has been a showcase for how scientific data and analyses are transformed into actionable information services and successful climate solutions for a wide range of user-communities. These methodologies must have the required temporal and granular details to target and track explicit emission activity where climate action is achievable.

We seek presentations from researchers, inventory compilers, government decision and policy makers, non-government and private sector service providers showing the use and impact of science-based methods of detecting, quantifying, and tracking GHG emissions, and, where possible, the resulting climate mitigation. These methods can involve direct-detection, inverse-modeling, and AI/ML data fusion/mining of statistical and observational activity data, as well as hybrid combinations of all these approaches.

Agricultural activities are one of the major contributors to trace gases in the atmosphere. Besides the contribution to methane (CH₄), nitrous oxide (N₂O), ammonia (NH₃), ground-level ozone (O₃), and various volatile organic compounds (VOCs) are triggered by agricultural activities. These trace gases play significant roles in biogeochemical cycles, affecting air quality and interplaying with climate change. Understanding the dynamics of the source and sink processes of these trace gases—from agricultural soils, crops, and the impact of diverse management practices—is essential for developing effective strategies or practices to mitigate their environmental impact.
This session, " Agricultural Trace Gas Dynamics and Air Quality: Innovative Approaches and Emerging Insights," aims to showcase the latest research and technological advancements in measuring and modeling trace gas exchanges and concentrations within agricultural ecosystems.
The session will welcome the following topics, but not limited to, (1) the impact of different agricultural management practices, such as tillage, mineral/organic fertilization, irrigation, crop rotation, and livestock management, on trace gas concentrations, emissions and depositions from a range of agroecosystems across the globe; (2) cutting-edge methodologies, such as ecosystem-scale monitoring, automated chamber systems, remote sensing technologies, and novel analytical tools for detecting VOCs and other trace gases; (3) the use of state-of-the-art modeling techniques, including artificial intelligence and machine learning, to extrapolate and predict gas dynamics patterns under various environmental and management scenarios; (4) challenges and opportunities associated with reducing the environmental footprint of agriculture.
We seek to bring together researchers, policymakers, and industry practitioners, especially the early career researchers, to join and contribute their fresh perspectives and ideas to this important discussion. Expected outcomes include fostering new collaborations, identifying research gaps on agricultural trace gas management and the challenges of climate change and air quality, and developing actionable recommendations for sustainable agricultural practices that may improve soil health, air quality, and global food security.

The deposition of reactive nitrogen to terrestrial ecosystems is a major threat to ecosystem integrity and biodiversity in Europe and other regions in the world. Yet, considerable uncertainties in the deposition estimates and underlying processes exist. These uncertainties also affect nature protection policies as well as emission regulation and mitigation strategies. This session welcomes studies investigating atmospheric deposition of reactive nitrogen species such as ammonia and oxidized nitrogen to terrestrial ecosystems. The session will greatly benefit from discussing different experimental approaches, using e.g. micrometeorological methods or deposition samplers, as well as process based and large-scale deposition modelling and the combinations thereof. Next to fundamental research on deposition processes and methods, studies creating the link to impacts and policy implications are especially encouraged, strengthening the connection between science output and societal application.

Nature-based solutions and eco-engineering interventions aim to work with natural processes to mitigate increased incidence in hydrometeorological extremes due to climate change. Examples of nature-based solutions include the addition of large wood or vegetation patches, floodplain reconnection, and the creation of blue-green urban infrastructures. The aims and design strategies for these interventions build on hydrological, biogeomorphic, and geochemical processes at multiple spatial and temporal scales including ecohydraulic interactions with vegetated canopy flows and large wood, sediment transport, and feedbacks with ecologic processes. Implementation and assessment frameworks for nature-based solutions are rapidly developing, with many challenges and open questions remaining. Therefore, an improved understanding of basic process-based function of nature-based solution designs and development of modelling strategies are urgently needed to ensure intervention efficacy meet the challenge of mitigating increasing extremes in a changing climate.

This session aims to form a broad range of cross-sector scholarship, including academic researchers, water managers, community stakeholders, and independent researchers. We invite you to submit abstracts broadly related to the following topics:
• Design of resilient nature-based solutions under a changing climate (floods versus droughts)
• Frameworks to evaluate nature-based solutions
• Modelling strategies of nature-based solutions: physical and numerical
• Field investigations of nature-based solutions including remote-sensing
• Implications of nature-based solutions on flow structures and sediment transport
• Ecological impacts and ecosystem services of nature-based solutions
• Management and maintenance of nature-based solutions
• Case studies of successful nature-based solution strategies including socio-economic aspects

A thin layer of Earth's surface sustains most of the planet's life, where a delicate interplay of biotic and abiotic factors constantly shifts and interacts. In this environment, remotely sensed (RS) signals are generated by the interaction of incoming, reflected, and emitted electromagnetic (EM) radiation with elements like atmospheric particles, vegetation, soil surfaces, and bodies of water. Vegetation, soil, and water serve as critical interfaces between terrestrial ecosystems and the atmosphere. These signals can be captured using optical, thermal, and microwave remote sensing, including parts of the EM spectrum where fluorescence can be detected.

This session invites contributions on strategies, methodologies, and approaches for analyzing, developing and integrating remote sensing products from different EM regions, angular configurations, and fluorescence data into models, including in-situ measurements for validation. We welcome presentations on topics such as climate change, food production, food security, nature conservation, biodiversity, epidemiology, air pollution from both human and natural sources (e.g., pollen), and related public health impacts. Additionally, insights into the assimilation of remote sensing and in-situ data in bio-geophysical and atmospheric models, as well as RS extraction techniques, are encouraged.

This session explores the potentials and limitations of various remote sensing applications in forestry, with the focus on the identification and integration of different methodologies and techniques from different sensors and in-situ data for providing qualitative and quantities forest information.
In general, remote sensing allows examining and gathering information about an object or a place from a distance, using a wide range of sensors and platforms. A key development in remote sensing has been the increased availability of data with very high temporal, spatial and spectral resolution. In the last decades, several types of remote sensing data, including optical, multispectral, radar, LiDAR from different platforms (i.e. terrestrial, mobile, UAV, aerial and satellite platforms), have been used to detect, classify, evaluate and measure the earth surface, including different vegetation cover and forest structure. For the forest sector, such information allows efficient quantification of the state and monitoring of changes over time and space, in support of sustainable forest management, forest and carbon inventory or for monitoring forest health and their disturbances. Remote sensing data can provide both qualitative and quantitative information about forest ecosystems. In a qualitative analysis, forest cover types and species composition can be classified, whereas the quantitative analysis can measure and estimate different forest structure parameters related to single trees (e.g. DBH, height, basal area, timber volume, etc.) and to the whole stand (e.g. number of trees per unite area, spatial distribution, etc.). However, to meet the various information requirements, different data sources should be adopted according to the application, the level of detail required and the extension of the area under study. The integration of in-situ measurements with satellite/airborne/UAV imagery, Structure from Motion, LiDAR and geo-information systems offers new possibilities, especially for interpretation, mapping and measuring of forest parameters and will be a challenge for future research and application.
One focus of this session will be on the outcomes of the 3DForEcoTech COST Action (https://3dforecotech.eu/) with its focus on developing protocols for data acquisition and processing, fusion for forest inventory and ecological applications and the establishment of open-data and open-source algorithm databases.

Quantifying and valuing biodiversity is essential for effective conservation strategies and addressing and mitigating biodiversity loss. Remote sensing is increasingly recognized as a valuable tool for monitoring various aspects of plant diversity, offering a solution to the spatial and temporal limitations of traditional field sampling. In addition, remote sensing can provide colocated information regarding ecosystem functions and services, which is crucial for understanding the role of plant diversity in maintaining ecosystem stability and resilience.
Despite its potential, remote sensing still faces numerous challenges in reliably quantifying plant diversity and bridging the gap with the field of ecology. There is a need for suitable and comparable field datasets that represent terrestrial ecosystems, which remote sensing can use to develop reliable estimation methods modeling frameworks and leverage new opportunities from new remote sensing missions and their integration. At the same time, closer collaboration with ecologists is necessary to understand their needs and demands better so that remote sensing outputs are valuable for a broader scientific community.
This session calls for recent studies showing advances in this field, with the scope of attracting scientists from other disciplines, notably ecology. We welcome both specialized and multidisciplinary contributions that advance the science of remote sensing of vegetation diversity or use its products in ecological studies. The session is also open to out-of-the-box approaches and biodiversity studies over other taxa.

Environmental data from large measurement campaigns and automated measurement networks are increasingly available and provide relevant information of the Earth System. However, such data are usually only available as point observations and only represent a small part of the Earth´s surface. Upscaling strategies are hence needed to provide continuous and comprehensive information as a baseline to gain insights on large-scale spatio-temporal dynamics. In the upscaling, machine learning algorithms that can account for complex and nonlinear relationships are increasingly used to link remote sensing datasets to reference measurements. The resulting models are then applied to provide spatially explicit predictions of the target variable, often even on a global scale.
Due to easy access to user-friendly software, model training and spatial prediction using machine learning algorithms is nowadays straightforward at first sight. However, considerable challenges remain: dealing with reference data that are not independent and identically distributed, accounting for spatial heterogeneity when scaling reference measurements to the grid cell scale, appropriately evaluating the resulting maps and quantifying their uncertainties, generating robust maps that do not suffer from extrapolation artifacts as well as the strategies for model interpretation and understanding.
This session invites contributions on the methodology and application of large-scale mapping strategies in different disciplines, including vegetation characteristics such as foliar or canopy traits and photosynthesis, soil characteristics such as soil organic carbon, or atmospheric parameters such as pollutant concentration. Methodological contributions can focus on individual aspects of the upscaling approach, such as the design of measurement campaigns or networks to increase representativeness, novel algorithms or validation strategies as well as uncertainty assessment.

This session, led by members of the NASA's ICESat-2 Science Team, aims to showcase the latest research and applications of ICESat-2 technology for mapping terrain and vegetation structure. Presentations will delve into key topics including: ICESat-2 data products, forest structure, biomass estimation, hydrology, disturbance detection, gridded map products, highlighting the invaluable contributions of ICESat-2 in advancing our understanding of terrestrial ecosystems. Moreover, we aim to provide an overview of the NASA ICESat-2 mission, including its instrumentation, data collection, mission objectives, and data validation, with a particular emphasis on its relevance to land and vegetation applications.


Session Topics:


i) Forest Structure and Biomass Assessment with ICESat-2
ii) Disturbance Detection and Monitoring with ICESat-2 (e.g. Fire, hurricanes, droughts)
iii) Synergies of ICESat-2 with Existing and Upcoming Earth Observation Missions for Land and Vegetation Applications (e.g., NASA’s GEDI, NISAR, SWOT, ESA’s Biomass)
iv) Gridded maps of terrain and/or vegetation parameters
v) Validation of ICESat-2 products over land and vegetation
vi) Open Science - Tools for ICESat-2 Data Processing

Primary production measures the rate of energy fixation in organic compounds and is one of the most fundamental ecological processes. Indeed, more and more projects are focused on mapping Gross Primary Production (GPP), Net Primary Production (NPP) and Net Ecosystem Production (NEP), as well as related variables such as Fraction of Absorbed Photosynthetically Active Radiation (FAPAR), Leaf Area Index (LAI), Soil Organic Carbon (SOC) and albedo. Different modeling strategies are used to derive these variables from remotely sensed data, providing and increasing the availability of spatio-temporal maps of primary production. Most importantly, the temporal trends of primary productions can be used to detect declining marine and terrestrial areas. Available products differ in spatial and temporal resolution and extent, modeling strategies, including machine learning and mechanistic models, and validation strategies. In fact, besides the cross-comparison of these products with each other, their accuracy can be validated against in-situ measurements, such as eddy covariance flux measurements from FLUXNET and similar databases. We invite contributions related to primary productivity modeling and mapping, to compare methodologies, accuracy, spatial and temporal scales, resolution, and derived statistics. In addition to identifying biologically degrading areas, these works enable global-scale studies of the impact of climate change on primary productivity and ecological stability. Finally, we also encourage studies that assess the impact of climate variables on spatiotemporal variations in primary productivity, enhancing our understanding of how these factors shape primary productivity patterns across different ecosystems and under the effect of climate change.

We call researchers working with continental and global-scale dataset for producing time-series of predictions of environmental variables especially the ones focused on the essential variables. Radeloff et al. (2024) (the Landsat science team) have proposed 13 essential and many more desirable/ aspirational products using medium resolution imagery referred to as “Medium-resolution satellite image-based products that meet the identified information needs for sustainable management, societal benefits, and global change challenges”. The desirable products include: maps of crop types, irrigated fields, land abandonment, forest loss agents, LAI/FAPAR, green vegetation cover fraction, emissivity, ice sheet velocity, surface water quality and evaporative stress. The aspirational land monitoring products include: forest types, and tree species, urban structure, forest recovery, crop yields, forest biomass, habitat heterogeneity and winter habitat indices, net radiation, snow and ice sheet surface melt, ice sheet and glacier melt ponds, sea ice motion and evaporation and transpiration. We will discuss modeling approaches, hybrid data science / process-based models and methods for accuracy assessment and visualization of uncertainty. Once one produced time-series of predictions, these can be further used to analyze trends and detect potential ecosystem degradation of restoration.

Sustainable agriculture and forestry face the challenges of lacking scalable solutions and sufficient data for monitoring vegetation structural and physiological traits, vegetation (a)biotic stress, and the impacts of environmental conditions and management practices on ecosystem productivity. Remote sensing from spaceborne, unmanned/manned airborne, and proximal sensors provides unprecedented data sources for agriculture and forestry monitoring across scales. The synergy of hyperspectral, multispectral, thermal, LiDAR, or microwave data can thoroughly identify vegetation stress symptoms in near real-time and combined with modeling approaches to forecast ecosystem productivity. This session welcomes a wide range of contributions on remote sensing for sustainable agriculture and forestry including, but not limited to: (1) the development of novel sensing instruments and technologies; (2) the quantification of ecosystem energy, carbon, water, and nutrient fluxes across spatial and temporal scales; (3) the synergy of multi-source and multi-modal data; (4) the development and applications of machine learning, radiative transfer modeling, or their hybrid; (5) the integration of remotely sensed plant traits to assess ecosystem functioning and services; (6) the application of remote sensing techniques for vegetation biotic and abiotic stress detection; and (7) remote sensing to advance nature-based solutions in agriculture and forestry for climate change mitigation. This session is inspired by the cost action program, Pan-European Network of Green Deal Agriculture and Forestry Earth Observation Science (PANGEOS, https://pangeos.eu/), which aims to leverage state-of-the-art remote sensing technologies to advance field phenotyping workflows, precision agriculture/forestry practices and larger-scale operational assessments for a more sustainable management of Europe’s natural resources.

Imaging the Earth’s surface and reconstructing its topography to study the landscape and (sub-) surface processes have strongly evolved during the past two decades, sometimes separately in different scientific disciplines of geosciences. New generations of satellites, Uncrewed Aerial Vehicles (UAVs), LiDAR systems, Structure-from-Motion (SfM) methods and deep learning approaches have made 2D, 3D and 4D (time series) data acquisitions easier, cheaper, and more precise. The spatial, temporal and spectral resolutions of the measurements cover wide ranges of scales, offering the opportunity to study the evolution of the ground surface from local to regional scale with unprecedented details. Coupled with the development of optimized workflows to digitize and process analogue data, such as historical aerial photographs, geoscientists now have various sets of tools to better understand our rapidly changing environments and distinguish the anthropogenic and natural causes of these changes.

However, challenges still exist at both methodological and application levels. How to properly acquire images and 3D data in harsh, remote or non-ideal environments? How to deal with complex camera distortions? How to process unknown, damaged and/or poorly overlapping digitized analogue photographs? How to properly assess the precision of these measurements and take these estimates into account in our results and interpretation? How to deal with heterogeneous time series? These questions exemplify situations commonly faced by geoscientists.

In the present session, we would like to gather contributions from a broad range of geoscience disciplines (geomorphology, glaciology, volcanology, hydrology, bio-geosciences, geology, soil sciences, etc.) to share our views and experience about the opportunities, limitations and challenges that modern 2D/3D/4D surface imaging offers, no matter the physical process or environment studied. Contributions can cover any aspects of surface imaging, from new methods, tools and processing workflows to precision assessments, time series constructions and specific applications in geosciences. We would like to especially emphasize contributions that cover 1) novel data acquisition and processing approaches (including image matching, camera distortion correction, complex signal/image and point cloud processing, and time series construction), 2) data acquisition in complex and fast-changing environments, and 3) innovative applications in geosciences.

Remote sensing has played a vital role in analyzing and mitigating the impacts of climate change and human activities on ecosystems. For the past three decades, satellite remote sensing has been a key tool for monitoring large areas at low cost with regular revisits. However, as the frequency of natural hazards increases, new technologies in remote and proximal sensing have emerged, aimed at improving data collection flexibility and resolution. One such technology is uncrewed aerial systems (UASs), equipped with various sensors (optical, microwave, thermal, etc.), bridging the gap between spaceborne and ground-based sensing. UASs offer ultra-high-resolution data and flexibility in flight scheduling, making them indispensable for natural and human-induced environmental risk prevention and decision-making.
UASs are particularly effective in mapping environmental changes caused by climate change, including erosion, slope instability, and riverbank degradation due to tectonic or human activities. They also support precision agriculture, monitoring crop impacts from extreme weather events, and enabling sustainable farming practices. The flexibility of UAS technology allows high-resolution data acquisition before and after events, facilitating risk detection and tailored recovery efforts.
This session will highlight the synergies between sensing technologies in the geoscience community, focusing on how these collaborations address the United Nations' Sustainable Development Goals (SDGs). Presentations are encouraged on topics such as the integration of satellite and UAS data, UAS applications in agriculture, and advancements in UAS configurations. Additionally, the session will discuss trends in UAS sensor technology and best practices for UAS operations in volcanic regions, offering a platform for showcasing the latest research and innovations in remote sensing.

Satellite measurements of our Earth from space are essential to our study of global
climate and weather patterns. Teasing out complexities in our Earth system requires a
framework of calibrated and curated remote sensors that can operate in space over
decadal periods. These instruments cover a variety of spectral, spatial, angular,
polarized, and coherent regimes and target specific Earth phenomena in the
atmosphere, surface, or oceans.

A comprehensive remote sensor calibration is required in order to
retrieve decadal and actionable climate trends with high accuracy and confidence.
Instrument teams follow an exhaustive pre-launch, on-orbit, vicarious, and cross-
calibration plan. Validating these efforts against radiative transfer simulations,
measurement trends over pseudo-invariant Earth targets, and dedicated field
campaigns with ground-network, airborne, or satellite-based intercomparisons help to
enhance and extend the original pre-launch characterization.

New and planned progressive missions with multi-angle polarimetry and/or multi-
instrument synergy are changing the way we understand our Earth system and how we
measure our observables. This session welcomes new research in pre-launch, on-orbit,
vicarious, and cross calibration activities on data from recently launched missions such
as PACE and EarthCARE and recent field campaigns, such as PACE-PAX, ARCSIX,
and ORCESTRA. Expected on-orbit performance studies for upcoming missions with
multi-angle polarimetry and/or multi-instrument synergy, such as 3MI, MAIA, and CO2M,
are highly encouraged as well.

Continuous monitoring of natural physical processes is crucial for understanding their behaviour. The variety of instruments available enhances data collection, aiding in the comprehension of these processes. Long-term data collection reveals trends and patterns, such as seasonal variations, multi-year cycles, and anthropogenic impacts (e.g., deforestation, urbanization, pollution). Conversely, short-term monitoring is vital for real-time decision-making, improving hazard assessment, risk management, and warning systems. Effective data analysis and innovative instrumentation contribute to developing mitigation and adaptation strategies. This session highlights the application of geosciences and geophysical instrumentation, including sensors in natural and laboratory environments, for monitoring natural phenomena and utilizing data systems to study these processes.
The session disseminates advanced research on natural physical processes and the use of scientific principles to address future challenges, including extreme climatic conditions. It encourages novel, interdisciplinary approaches to monitoring, aiming to establish historical baselines. This session seeks to bridge scientific knowledge and technological advancements to improve monitoring and understanding of natural physical processes. The session is inter- and transdisciplinary (ITS), covering topics such as:

1. Destructive and Non-Destructive Sensing Techniques, including contactless and remote sensing methodologies.
2. Monitoring System Developments for understanding hydro-meteorological processes, glaciers, soil erosion, settlements, liquefaction, landslides, earthquakes, volcanic events, and wildfires.
3. Real-Time Monitoring Systems, integrating geoscience data with Building Information Modelling (BIM), digital twins, robotic monitoring, and automation for improved decision-making.
4. Advances in Data Systems for efficient real-time monitoring and processing of large data volumes using Cloud Data Platforms, Distributed and Scalable Data Systems, Real-Time Data Processing, AI, Machine Learning, Data Privacy and Security, and Edge Computing.
5. Storage Technologies and Data Integration, including advancements in Graph Databases, Data Interoperability, and Multi-Model Databases.
6. Intelligent data analysis approaches to analyse accurate and precise interpretation of big data sets driven by various technologies.

The session will assemble current knowledge on Transient Climate Response to cumulative carbon Emissions (TCRE) and Zero Emissions Commitment (ZEC) in the context of reducing uncertainty in remaining carbon budgets and reversibility.

Specific topics could include:
- Understanding TCRE and ZEC components, frameworks for investigating the processes and contributions to TCRE, ZEC, and identifying where uncertainty comes from, focus on Land/Ocean processes (e.g., CO2 fertilization, permafrost; ocean co-uptake of heat/CO2)
- Observational or Emergent constraints
- Use of simple models/emulators and model hierarchy.

Land–atmosphere interactions often play a decisive role in shaping climate extremes. As climate change continues to exacerbate the occurrence of extreme events, a key challenge is to unravel how land states regulate the occurrence of droughts, heatwaves, intense precipitation and other extreme events. This session focuses on how natural and managed land surface conditions (e.g., soil moisture, soil temperature, vegetation state, surface albedo, snow or frozen soil) interact with other components of the climate system – via water, heat and carbon exchanges – and how these interactions affect the state and evolution of the atmospheric boundary layer. Moreover, emphasis is placed on the role of these interactions in alleviating or aggravating the occurrence and impacts of extreme events. We welcome studies using field measurements, remote sensing observations, theory and modelling to analyse this interplay under past, present and/or future climates and at scales ranging from local to global but with emphasis on larger scales.

The spatial organization and structure of soils, known as the soil architecture, has traditionally been assumed to be stable over timescales relevant to soil functions, such as carbon, nutrient, and water cycling. However, this assumption does not always hold, especially under biotic activity, changing land use and shifting climate conditions. Dynamics of pore structure and soil aggregates and redistribution of soil material through processes such as mixing and erosion continuously reshape the soil architecture over short to long timescales, affecting the functioning of soils. To comprehensively understand soil functionality in a changing world, it is imperative to view soils as dynamic, four-dimensional systems.

This session invites presentations that study soil dynamics using numerical and statistical modelling. The focus will be on the development of model-based representations, or digital twins, of soil systems to study soil processes, dynamics, and functions from the pore to the landscape scale and from diurnal dynamics to millennial evolution. By bringing together modellers and models that work on different spatiotemporal scales, we aim at synergies between soil hydrology, soil physics, soil geography and soil ecology to develop holistic models that consider soils and their functions as dynamic systems.

Understanding the exchange of CO2 and other greenhouse gases (GHGs) between land, atmosphere, and ocean is crucial for mitigating climate change and supporting climate agreements. However, significant uncertainties remain due to challenges in integrating experimental, observational, and theoretical research across scales. Data-driven machine learning (ML) approaches have become popular for studying different components of the carbon cycle, but current artificial intelligence (AI) systems rarely provide a comprehensive view of the entire Earth system. This session aims to connect diverse research communities to discuss AI-driven research on the carbon cycle.

We encourage submissions on all aspects of the carbon cycle, including the atmosphere, biosphere, ocean, and human impacts. ML can enhance top-down and bottom-up approaches for quantifying land and ocean fluxes, constraining carbon budgets and carbon stocks, and mapping CO2 and CH4 through atmospheric tracer transport. This is crucial for tasks such as partitioning land fluxes into photosynthesis and respiration, estimating carbon stocks in soils and biomass, etc. This session particularly targets works that integrate diverse data sources that are not traditionally combined, such as remote sensing data with eddy covariance flux measurements.

Recent advances in numerical weather prediction have shown the effectiveness of deep neural networks, particularly transformers. Emerging "Foundation Models" integrate diverse data streams to address multiple tasks within a single AI system. Classical algorithms like random forests, Gaussian processes, and gradient-boosting trees remain useful due to their efficiency and ease of use. Uncertainty quantification and explainable AI enhance ML methods by revealing key variables.

In summary, this session welcomes all submissions that leverage machine learning for carbon cycle research, including but not limited to:
- Machine learning for integrating remote sensing data with in-situ observations.
- Hybrid modeling for enhanced inference of parameters and responses of key processes in the carbon cycle.
- Mapping of stocks, fluxes, and other carbon-related quantities.
- Emulators to speed up conventional models, such as atmospheric tracer transport models for GHGs.
- ML methodologies for improving uncertainty quantification, prediction accuracy, explainability, or sample efficiency.
- Model-data integration to better understand CO2 and CH4 fluxes.