Tropical ecosystems are biomes of global significance due to their large biodiversity, carbon storage capacity, and their role in the hydrological cycle. Historic and recent human activities have, however, resulted in intensive transformation of the tropical ecosystems in the Amazon, Central America, Central Africa and in South East Asia impacting the cycling of nutrient, 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 upon changing climate and land use, and the impact this will have on local up to global scale.
This session aims at bringing together scientists who investigate the functioning of the tropical ecosystems across spatial and temporal scales by means of remote and in-situ observational, modelling, and theoretical studies. Particularly welcome are presentations of novel, interdisciplinary approaches and techniques.

Land use and land cover change (LULCC), including land management, has the capacity to alter the climate by disrupting land-atmosphere fluxes of carbon, water and energy. Thus, there is a particular interest in understanding the role of LULCC as it relates to climate mitigation and adaptation strategies. Much attention has been devoted to the biogeochemical impacts of LULCC, yet there is an increasing awareness that the biogeophysical mechanisms (e.g. changes in surface properties such as albedo, roughness and evapotranspiration) should also be considered in climate change assessments of LULCC impacts on weather and climate. However, characterizing biogeophysical land-climate interactions remains challenging due to their complexity. If a cooling or a warming signal emerges depends on which of the biogeophysical processes dominates and on the size and pattern of the LULCC perturbation. Recent advances exploiting Earth system modelling and Earth observation tools are opening new possibilities to better describe LULCC and its effects at multiple temporal and spatial scales. This session invites studies that improve our general understanding of climate perturbations connected to LULCC from both biogeophysical and biogeochemical standpoints, and particularly those focusing on their intersection. This includes studies focusing on LULCC that can inform land-based climate mitigation and adaptation policies. Both observation-based and model-based analyses at local to global scales are welcome.

Phosphorus (P) is essential to life, and as a key limiting nutrient, regulates productivity in terrestrial and aquatic systems. Strong geochemical interactions between P and other elements control the mobility and bioavailability of P in the environment, necessitating a coupled understanding of element cycles influencing P. At the same time P provides perhaps the most topical example of a critical resource element whose use is currently inefficiently managed. Leakage of mined P into the environment through a variety of processes (e.g. excess chemical fertiliser usage, or effluent discharges) is responsible for eutrophication and the acceleration of natural P cycling in terrestrial and aquatic systems. This puts P at the forefront of environmental and societal concerns and demands that our biogeochemical knowledge of P cycling ought to be developed through interdisciplinary research. This session aims to explore biogeochemical P cycling in the context of benefitting ‘systems understanding’ spanning terrestrial and aquatic compartments.

Topics included will explore:
Links between P and wider element cycles, for example with other macro- and micro- nutrients and controls of P availability through geochemical parameters such as Fe;
P cycling studies that bring into focus the interplay of biotic and abiotic controls within, and between, environmental compartments;
Drivers of change (climate, management, societal) acting on the coupling of P with other element cycles.
Processes, modelling and management against a background of the key issues for: P release from soil to plants; P release from soil to water; long term P supplies and the global P cycle.
Sustainable use of P, recovering of P from natural and waste water, managing P fluxes in agricultural areas.

Extreme climate and weather events, associated disasters, geohazards and emergent risks interact with other stressors, especially growing anthropogenic pressures, and are so becoming increasingly critical in the context of global environmental change. They are a potential major threat to reaching the Sustainable Development Goals (SDGs) and one of the most pressing challenges for future human well-being and safety.
This session explores the linkages between extreme climate and weather events, geohazards, associated disasters, societal dynamics and resilience.
Emphasis is laid on 1) Which impacts are caused by extreme climate events (including risks emerging from compound events) and cascades of impacts on various aspects of ecosystems and societies? 2) Which feedbacks across ecosystems, infrastructures and societies exist? 3) What are key obstacles towards societal resilience and reaching the SDGs, while facing climate extremes? 4) What can we learn from past experiences? 5) What local to global governance arrangements best support equitable and sustainable risk reduction?
Nowadays, to answer this last question, the careful application of social media and crowdsourcing (SMCS) begins to make a contribution, notably in the field of geosciences. SMCS have been integrated into crisis and Disaster Risk Management (DRM) for improved information gathering and collaboration across communities, and for collaboratively coping with critical situations. Numerous governments and EU-funded projects have been exploring the implementation and use of SMCS by developing and adopting new technologies, procedures, and applications. The effectiveness of SMCS on European disaster resilience, however, remains unclear, due to the diversity among disaster risk perception and vulnerability. In general, this second part addresses ways to govern and understand the effectiveness of SMCS for Disaster Risk Management and the related Disaster Resilience is focused.
In this session we welcome empirical with practical applications, theoretical and modelling studies from local to global scale from the fields of natural sciences, social sciences, humanities and related disciplines since the creation of novel effective approaches necessitates a coordinated and coherent effort between them.

A grand challenge facing society in the coming decades is to feed the growing human population in a sustainable and healthy manner. This challenge is central to many of the United Nations Sustainable Development goals (SDGs), including the zero hunger goal but also those for human health, water, terrestrial biodiversity and sustainable production and consumption.
This problem is made more complex by an increasingly globalised food system and its interactions with a changing climate. Agri-food system actors - including policy makers, corporations, farmers, and consumers - must meet this challenge while considering potentially conflicting priorities, such as environmental sustainability (e.g., minimising disturbance to ecosystems via greenhouse gas emissions and the use of water, land, fertilisers and other inputs), economic viability (e.g., revenues for food producers and guaranteed access for consumers), nutritional balance and quality (e.g., addressing overconsumption and undernourishment), and resilience to climate change.
This growing complexity of agri-food systems, which can involve global supply chains and difficult environmental and societal tradeoffs, needs to be better understood.
The type of product (e.g. plant or meat based, fresh or processed), as well as the location and method of production, can play an important role in improving the nutritional quality and environmental sustainability of global food production, to enable healthy and sustainable diets. Quantifying and assessing these multiple outcomes while accounting for the linkages, interconnections, and scales of local and global supply chains will be essential for informing decisions aimed at developing sustainable and resilient agri-food systems.
This session welcomes submissions that quantify and assess a range of outcomes from agri-food systems across multiple spatial and temporal scales, and the trade-offs or synergies between them. The session will include studies providing improved methods for quantifying multiple environmental, economic or social dimensions, studies that incorporate the role of food trade into solution-development, and studies that seek to achieve multiple sustainability goals together.

The Earth’s subsurface hosts enormous methane volumes either trapped in the shallow sediments, gas hydrates and permafrost, or naturally escaping the sediment through methane seepage to enter the hydrosphere/atmosphere. Such environments are highly sensitive to climate change. Despite an increasing awareness about the positive feedback between global warming and methane seepage, the response of these complex and dynamic systems to climate change is still unclear due to complex geo/hydro/atmosphere interactions.
Fossil cold seeps, long-term observatory studies and modern examples form the foundations to understand the mutual dependences between climate and seepage, and to develop robust models to forecast future scenarios at the Earth-system scale. For this session, we welcome geologists, geophysicists, geochemists, biologists, model developers, and any others who have contributed to new case studies in modern and fossil hydrocarbon seeps in the marine and terrestrial environment, gas hydrate and permafrost settings, to describe both new methods/technologies and the scientific outcomes.

Using a wide range of sensors and platforms, remote sensing allows examining and gathering information about an object or a place from a distance. 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, radar, LiDAR from terrestrial, UAV, aerial and satellite platform, have been used to detect, classify, evaluate and measure the Earth surface, including different vegetation covers and forest structure. For the forest sector, such information allow efficient 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 qualitatively and quantitatively 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, 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 offer new possibilities, especially for interpretation, mapping and measuring of forest parameters and will be a challenge for future research and application. 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.

Fire is an essential Earth system process that is rapidly changing in response to climate and human land use changes. Climate, vegetation and human activity regulate fire occurrence and spread, but fires also feedback to them in multiple ways. This session welcomes contributions on all aspects of linkages between fire, vegetation, climate, and humans to share recent advances and foster interdisciplinary discussions. We encourage all abstracts that explore the role of fire in the Earth system at any temporal and spatial scale using modeling, field and laboratory observations, and/or remote sensing, with an emphasis on studies that advance our understanding on interactions between fire and (1) weather, climate, and atmospheric chemistry, (2) biogeochemical cycles, land water and energy budgets, and vegetation composition and structure, and (3) human land management (e.g. impact of fire on air and water quality, deforestation, human health, and economy). We also welcome contributions focusing on fire characterization, including (4) fire behavior and emissions (e.g. fire duration, intensity, emission factors, emission height, smoke transport), (5) spatial and temporal changes of fires in the past, present, and future, (6) fire products and models, and their validation and error/bias assessment, and (7) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems.

Terrestrial ecosystems are being exposed to warming and to more frequent and intense drought and rainfall events as a result of climate change. Such changes can have strong implications for biogeochemical cycling and the functioning of soils. Understanding the mechanisms that control the responses to environmental stress is critical for improving predictions on the resistance and resilience of terrestrial ecosystems on a changing world.

The aim of this session is to bridge the knowledge of different disciplines to elucidate the processes and feedbacks underpinning the biogeochemical response to climate change, with emphasis on warming, drought, and drying-rewetting events. This session will give a broad overview of empirical and modelling studies across different scales, considering how climate change affects terrestrial biogeochemistry and the interactions between soil microorganisms, plants and fauna. We will focus on the resilience and the associated recovery dynamics of soil biota to environmental disturbances, as well as on their resistance or adaptation mechanisms to climate change. We will bring together researchers from different environments and create a discussion platform to review the current state-of-the-art, identify knowledge gaps, share ideas, and tackle new challenges in the field.

Ecosystem responses to climate change depend on both long-term and dynamic feedbacks occurring between soils, plants and microbial communities. Soil resources and microbial nutrient mineralization mediate vegetation growth. In turn, plants control soil properties through the production of organic residues which are decomposed in the soil, the supply of photosynthates to the rhizosphere, as well as the association with belowground communities. The interactive effects of these responses in the context of changing environmental conditions have a key influence on soil biogeochemistry and the belowground storage of carbon. In this session we invite contributions from manipulative field experiments, observations in natural-climate gradients, and modelling studies that explore the impact of climate change on plant-growth dynamics, microbial diversity and metabolism, as well as soil biogeochemical cycling. Submissions that adopt novel approaches (e.g. molecular, isotopic) or synthesize large-scale outputs focusing on plant-soil-microbe feedbacks to warmer temperatures or water limitation are also highly welcome.

Vegetation, soils and water resources have interacted and co-evolved over Millions of years, shaping our current ecohydrological systems. Vegetation still responds rapidly to changing environmental conditions, including rising atmospheric carbon dioxide concentrations, climate change, soil degradation and hydrologic modifications. Prediction of these co-evolutionary and adaptive processes is a major scientific challenge, as it requires understanding of the general underlying principles and constraints governing plant-environment interactions.

This session aims to bring together collected knowledge about organising principles guiding co-evolutionary processes in biology, hydrology and physics, including theoretical, modelling, observational and experimental studies. We solicit contributions to all aspects of our quantitative understanding of principles such as natural selection, relevant thermodynamic principles (e.g. MaxEnt, maximum power, maximum entropy production) or biological optimality and the associated cost-benefit trade-offs.

Wide-spread permafrost thaw is expected to amplify the release of previously frozen material from terrestrial into aquatic systems: rivers, lakes, groundwater and oceans. Current projections include changes in precipitation patterns, active layer drainage and leaching, increased thermokarst lake formation, as well as increased coastal and river bank erosion that are further enhanced by rising water temperatures, river discharge and wave action. In addition, subsea permafrost that formed under terrestrial conditions but was later inundated might be rapidly thawing on Arctic Ocean shelves. These processes are expected to substantially alter the biogeochemical cycling of carbon but also of other elements in the permafrost area.

This session invites contributions on the mobilization of terrestrial matter to aquatic systems in the permafrost domain, as well as its transport, degradation and potential interaction with autochthonous, aquatic matter. 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.

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 unraveling the complexities of nitrogen transformations and transport will also be of interest.

The critical zone comprises the Earth's permeable near-surface layer from the top of the canopy to the bottom of the groundwater. It is the zone where hydrosphere, atmosphere, pedosphere and geosphere interact with the biosphere. This fragile skin of our planet, which supports the life and survival of humans maintaining food production and drinking water quality, is endangered by threats such as climate change and land use change.
New approaches and innovative modeling strategies are needed to understand these complex interactions between hydrological, biogeochemical cycles and human resilience processes that may govern critical zone system dynamics, including sources, dynamics and chemistry of water, models to quantify external influences like human activities or erosion, weathering rate, water transfer in the frame of global change and biolological feedback mechanisms.

This session focuses on the advancing proxies that may address pressing interdisciplinary scientific questions in coupling various disciplines like hydrology, soil science and biogeochemistry that cover single-site investigations, targeted experiments, remote sensing studies, large data compilations and modelling. This will be illustrated in this session through studies regarding the critical zone as a whole or within its different compartments, including the different environmental processes (geological, physical, chemical, and biological), their couplings and reactive transport modeling, and exploring the cities resilience.

The storage, cycling and availability of Nitrogen (N), Carbon (C) and Phosphorus (P) in soils are widely researched topics; however, less investigation has been carried out regarding the coupling and interaction of the C-N-P cycles. This is especially relevant as the quantity and quality of these three elements and their proportions and interactions control fundamental soil functions such as soil fertility and microbial activity, which have profound impacts on key ecosystem services such as primary productivity, carbon capture or biodiversity.
Beside this, there is an urgent need to implement sustainable methodologies, which help to preserve soil quality and mitigate soil degradation. Under these assumptions, traditional and novel soil organic matter amendments will help us to maintain both agricultural yields as well as soil preservation. Increase of organic matter level in soil is not only a question of soil fertility but also a necessity of soil health maintenance and fighting against desertification.
In this session, we call for submissions on a wide range of topics covering C, N, and P cycles in soils, with a special focus on studies assessing their interactions, as well as the current research and latest advances focused on maintaining soil organic matter quantity and quality and therefore preserving soil functionality.
Our aim is to cover also a wide range of spatial scales, from microbial stoichiometry to ecosystem functioning, as well as a range of methodologies, from the microscale process understanding at laboratory scale up to field-based and modelling approaches. Studies in all types of soil and ecosystems, from natural forest to agricultural or urban soils, are welcome.

Meet editors of internationally renowned journals in biogeosciences and soil system science and gain exclusive insights into the publishing process. After a short introduction into some basics, we will start exploring various facets of academic publishing with short talks given by the editors on - What are the duties and roles of editors, authors and reviewers? - How to choose a suitable journal for your manuscript and what is important for early career authors? - How can early career scientists get involved in successful peer-reviewing? - What is important for appropriate peer-reviewing? - What are ethical aspects and responsibilities of publishing? - Together with the audience and the editors, we will have an open discussion of all steps and factors shaping the publication process of a manuscript. This short course aims to provide early career scientists across several EGU divisions (e.g. BG, SSS, NH and GM) the opportunity of using first hand answers of experienced editors of international journals to successfully publish their manuscripts and get aware of the potentials and pitfalls in academic publishing.

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.

Viticulture is one of the most important agricultural sectors of Europe with an average annual production of 168 million hectoliters (54% of global consumption). The concept of “Terroir” links the quality and typicity of wine to the territory, and, in particular, to specific environmental characteristics that affect the plant response (e.g. climate, geology, pedology). The environmental factors that drive the terroir effect vary in space and time, as well as soil and crop management.
Understanding the spatial variability of some environmental factors (e.g. soil) is very important to manage and preserve terroirs and face the current and future issue of climate change. In this sense, it is important to stress that in the last decade, the study of terroir has shifted from a largely descriptive regional science to a more applied, technical research field, including: sensors for mapping and monitoring environmental variables, remote sensing and drones for crop monitoring, forecast models, use of microelements and isotopes for wine traceability, metagenome approach to study the biogeochemical cycles of nutrients.
Moreover, public awareness for ecosystem functioning has led to more quantitative approaches in evidencing the relations between management and the ecosystem services of vineyard agroecosystems. Agroecology approaches in vineyard, like the use of cover crops, straw mulching, and organic amendments, are developing to improve biodiversity, organic matter, soil water and nutrient retention, preservation from soil erosion.
On those bases, the session will address the several aspects of viticultural terroirs:
1) quantifying and spatial modelling of terroir components that influence plant growth, fruit composition and quality, mostly examining climate-soil-water relationships; 2) terroir concept resilience to climate change; 3) wine traceability and zoning based on microelements and isotopes; 4) interaction between vineyard management practices and effects on soil and water quality as well as biodiversity and related ecosystem services.

This session will focus on the emerging discipline of Conservation Paleobiology that uses the data from the fossil record and sedimentary archives to inform biodiversity conservation and ecosystem management. Even though humans have altered ecosystems for millennia, direct ecological observations rarely encompass more than the last few decades. At the same time, the accelerating pace of global climate change requires better understanding of the long-term resilience and adaptive capacities of ecosystems facing multiple stressors. The youngest fossil record can offer high-resolution insights into ecosystem change on timescales well beyond the limits of ecological monitoring, enabling the reconstruction of ecological baselines and natural range of variability. Additionally, the pre-Quaternary geologic record provides a series of natural experiments allowing assessment of biotic responses to major environmental perturbations, strengthening the theoretical foundations of conservation science.

We invite presentations offering both the near-time and deep-time perspective on ecological and evolutionary processes operating during times of rapid environmental changes, ranging from the Anthropocene biodiversity crisis to Phanerozoic mass extinction events. We also welcome contributions highlighting potential biases affecting the fossil record by linking stratigraphic, taphonomic and ecological patterns. We hope to stimulate discussion on novel opportunities and limitations of using different types of geohistorical data to address some of the most urgent questions in Conservation Biology.

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. Interpreting these archives requires fundamental understanding of mineral formation 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.

Documenting the diversity of human responses and adaptations to climate, landscapes, ecosystems, natural disasters and the changing natural resources availability in different regions of our planet, cross-disciplinary studies in Geoarchaeology provide valuable opportunities to learn from the past. Furthermore, human activity became a major player of global climatic and environmental change in the course of the late Quaternary, during the Anthropocene. Consequently, we must better understand the archaeological records and landscapes in context of human culture and the hydroclimate-environment nexus at different spatial and temporal scales. This session seeks related interdisciplinary papers and specific geoarchaeological case-studies that deploy various approaches and tools to address the reconstruction of former human-environmental interactions from the Palaeolithic period through the modern. Topics related to records of the Anthropocene from Earth and archaeological science perspectives are welcome. Furthermore, contributions may include (but are not limited to) insights about how people have coped with environmental disasters or abrupt changes in the past; defining sustainability thresholds for farming or resource exploitation; distinguishing the baseline natural and human contributions to environmental changes. Ultimately, we would like to understand how strategies of human resilience and innovation can inform our modern strategies for addressing the challenges of the emerging Anthropocene, a time frame dominated by human modulation of surface geomorphological processes and hydroclimate.

One of the most challenging sustainable goals of the UN 2030 Agenda and other international agreements is that urban systems have to increase well-being and health. Indeed, these networked systems already host more than half of the world's population and are going to host most of its growth, while they have been mostly designed and managed with limited visions, in particular with respect to their geophysical environment.
This goal got an unforeseen acuity with the Covid-19 pandemic, starting with the confinement strategies that radically brought into question the functioning of these systems, e.g., drastically reducing mobility and breaking its ever increasing trend. Covid-19 was not without precursor (e.g., SARS, MERS) and will not be without successors.

Long term visions based on transdisciplinary scientific advances are therefore indispensable, particularly from the geoscience community. As a consequence, this session calls for contributions from data-driven and theory-driven approaches of urban health under global change. This includes:
- qualitative improvements of epidemic modelling, as trans-disciplinary and nonlinear as possible
- possible interplays between meteorological and/or climate drivers and epidemic/health issues
- novel monitoring capabilities (including contacts tracking), data access, assimilation and multidimensional analysis techniques
- managing field works, geophysical monitoring and planetary missions
- how to have the highest science output during corona pandemic
- a fundamental revision of our urban systems, their greening as well as their mobility offer
- a particular focus on urban biodiversity, in particular to better manage virus vectors
- urban resilience must include resilience to epidemics, and therefore requires revisions of urban governance.

Plastic contamination is a global concern. With increasing usage and disposal of plastics, waste management is often inefficient in processing the volumes of plastic discarded. A large proportion of plastic waste accumulates in the natural environment where clean-up is difficult, if not impossible. This results in the plastic contamination persisting in the environment for many years, having the potential to cause long-term ecological harm, ultimately affecting humans.

To mitigate plastic pollution and find solutions to reduce harmful effects, a better understanding of the sources and pathways of plastics in the environment is needed. This should inform social and industrial practices, as well as advise on regulatory changes to address plastic management. This will also promote developing a roadmap towards the development and safe usage of alternative materials, to reduce environmental and health implications. The approach aims at bringing together academics from a variety of research fields and citizen science initiatives along with stakeholders from civil society and industry, as well as regulators and policymakers. The task requires collaboration across disciplines, from environmental sciences, including biology and chemistry, geosciences, atmospheric sciences and oceanography, to materials science, social sciences and economics.

This session will address the linkages and cross-disciplinary collaborations required for effective progress in this field. We specifically invite presentations featuring successes and challenges in collaboration between academia, industry and regulators. Presentations on tracking plastics and on elucidating connecting mechanisms from human activities through to environmental abundance and impact are encouraged. Studies on biota-plastic interactions, plastic fluxes linked to human activities and environmental changes (from synoptic events to climate change) and studies linking plastic characteristics to toxicological impacts (chemistry, materials science and ecotoxicology) are welcomed.

This is a linked session co-organised and co-designed with a session at the annual meeting of SETAC Europe (Society of Environmental Toxicology and Chemistry), by connected convenor teams, to ensure full integration and input across disciplines. Outputs from the linked sessions will be disseminated widely across SETAC and EGU members through online resources, with a view to effective knowledge sharing and building collaborations.

Nature-based Solutions (NBS) are reframing discussion and policy responses worldwide to environmental challenges. Thus, NBS is of growing implementation, supported namely by the EU political agenda (e.g., green deal), as a way to attain the United Nations (UN) Sustainable Development Goals (SDG), and to reinforce the New Urban Agenda. The NBS concept recognise the importance of nature and outline requirements for a systemic and holistic approach to environmental change, based on an understanding of the structure and functioning of ecosystems, and the social and institutional context within which they are situated. Furthermore, there is a growing recognition that human activities exert pressure on natural resources affecting the ecosystem dynamics and therefore the nexus (synergies and trade-offs) between their different functions and services. However, quantification of existing NBS’ effectiveness, their operationalisation and replication in different environmental settings has not been presented in such a way that allows them to be both widely accepted and incorporated in policy development and in practical implementation to achieve the UN SDGs.
This session aims to discuss and advance knowledge of innovative NBS approaches to face environmental challenges, such as water supply and management, agricultural production and healthy ecosystems, and simultaneously provide better understanding of associated social-ecological interactions, contributing to enhance the scientific basis for sustainable development and resilience.
This session seeks to:
- Better understanding of advantages and disadvantages of NBS to address global environmental and societal challenges;
- Studies on adaptation and mitigation options for the effect of climate change on water provisioning and livelihoods;
- New methods and tools to investigate the role of NBS in the context of environmental change; in particular, the effectiveness of NBS for hydro-meteorological risk reduction at landscape/watershed scale;
- New insights, methodologies, tools and best practices enabling successful implementation and upscaling of NBS in multiple contexts;
- Identifying opportunities for and barriers to NBS within current regulatory frameworks and management practices;
- Presenting overviews and case studies of NBS projects that also involve the private sector and market-based mechanisms;
- NBS towards achieving the Sustainable Development Goals (SDGs).

The study of deep-time (pre-Quatrenary) climate evolution is important not only for understanding Earth’s habitable history but also for providing insights to present and future changes of the Earth system. To investigate deep-time climate, several international modelling intercomparsion projects, for example DeepMIP, MioMIP, PlioMIP, have been initiated. All these MIPs pay attention to the Cenozoic climate. However, relatively fewer modelling studies simulate climate in deeper time before the Cenozoic. This session invites works on deep-time climate simulations and reconstructions over the tectonic time scales, including, but not limited to, idealized and comprehensive model simulations, geological, geochemical, and paleontological reconstructions. We wish this session could integrate our knowledge of deep-time climate and environment evolution in the spirit of an integrated Earth system.

At the 2015 Paris COP21 climate conference, 195 countries committed to reduce their greenhouse gas emissions and make efforts to significantly limit man-made global warming to below 2°C above pre-industrial levels. France and Germany joined forces in this fight against global warming by creating the “Make Our Planet Great Again” research initiative covering research in Earth system science that aims to better understand climate change and its impacts on natural and socio-economic systems. In this interdisciplinary session, we welcome data- and model-based research undertaken within, but also outside this international initiative. We welcome contributions that provide new insights into the mechanisms of past, present and future climate changes and the associated impacts on the oceans, the cryosphere, coastal regions, and terrestrial systems. Innovative research contributions that can lead towards the ultimate goals of the Paris Agreement ranging from basic research to solution-oriented research are also encouraged.

In 2015, the UN Sustainable Development Goals and the Paris Agreement on climate recognised the deteriorating resilience of the Earth system, with planetary-scale human impacts constituting a new geological epoch: the Anthropocene. Earth system resilience critically depends on the nonlinear interplay of positive and negative feedbacks of biophysical and increasingly also socio-economic processes. These include dynamics in the carbon cycle, large-scale ecosystems, atmosphere, ocean, and cryosphere that can absorb geophysical shocks (e.g. volcanic eruptions), as well as the dynamics and perturbations associated with human activities.

Maintaining Earth in the Holocene-like interglacial state within which the world’s societies evolved over the past ~10,000 years will require industrialised societies to embark on rapid global-scale socio-economic transformations. In addition to incrementally increasing environmental hazards, there is a risk of crossing tipping points in the Earth system triggering partly irreversible and potentially cascading changes.

In this session we invite contributions on all topics relating to Earth resilience, such as assessing the biophysical and social determinants of the Earth’s long-term stability, negative feedback processes, modelling and data analysis and integration of nonlinearity, tipping points and abrupt shifts in the Earth system, and the potential for rapid social transformations to global sustainability.

Remaining carbon budgets specify the maximum amount of CO2 that may be emitted to stabilize warming at a particular level (such as the 1.5 °C target), and are thus of high interest to the public and policymakers. Yet, there are many sources of uncertainty which make it challenging to estimate the remaining carbon budget in real world conditions, especially for ambitious mitigation targets.

This session aims to further our understanding of the climate response under different emission scenarios, with particular interest in emission pathways towards net-zero targets, and to advance our knowledge of associated carbon budgets consistent with meeting various levels of warming. We invite contributions that use a variety of tools, including fully coupled Earth System Models, Integrated Assessment Models, or simple climate model emulators.

We welcome studies exploring different aspects of climate change in response to future emission scenarios, in addition to studies exploring carbon budgets and the TCRE framework, including: the governing mechanisms behind linearity of TCRE and its limitations, effects of different forcings and feedbacks (e.g. permafrost carbon feedback) and non-CO2 forcings (e.g. aerosols, and other non-CO2 greenhouse gases), estimates of the remaining carbon budget to reach a given temperature target (for example, the 1.5 °C warming level from the Paris Agreement), the role of pathway dependence and emission rate, the climate-carbon responses to different emission scenarios (e.g. SSP scenarios, idealized scenarios, or scenarios designed to reach net-zero emission level), and the behaviour of TCRE in response to artificial carbon dioxide removal from the atmosphere (i.e. CDR or negative emissions). Contributions from the fields of climate policy and economics focused on applications of carbon budgets and benefits of early mitigation are also encouraged.

The session gathers geoscientific aspects such as dynamics, reactions, and environmental/health consequences of radioactive materials that are massively released accidentally (e.g., Chernobyl and Fukushima nuclear power plant accidents, wide fires, etc.) and by other human activities (e.g., nuclear tests).

The radioactive materials are known as polluting materials that are hazardous for human society, but are also ideal markers in understanding dynamics and physical/chemical/biological reactions chains in the environment. Thus, the radioactive contamination problem is multi-disciplinary. In fact, this topic involves regional and global transport and local reactions of radioactive materials through atmosphere, soil and water system, ocean, and organic and ecosystem, and its relation with human and non-human biota. The topic also involves hazard prediction and nowcast technology.

By combining 35 years (> halftime of Cesium 137) monitoring data after the Chernobyl Accident in 1986, 10 years dense measurement data by the most advanced instrumentation after the Fukushima Accident in 2011, and other events, we can improve our knowledgebase on the environmental behavior of radioactive materials and its environmental/biological impact. This should lead to improved monitoring systems in the future including emergency response systems, acute sampling/measurement methodology, and remediation schemes for any future nuclear accidents.

The following specific topics have traditionally been discussed:
(a) Atmospheric Science (emissions, transport, deposition, pollution);
(b) Hydrology (transport in surface and ground water system, soil-water interactions);
(c) Oceanology (transport, bio-system interaction);
(d) Soil System (transport, chemical interaction, transfer to organic system);
(e) Forestry;
(f) Natural Hazards (warning systems, health risk assessments, geophysical variability);
(g) Measurement Techniques (instrumentation, multipoint data measurements);
(h) Ecosystems (migration/decay of radionuclides).

The session consists of updated observations, new theoretical developments including simulations, and improved methods or tools which could improve observation and prediction capabilities during eventual future nuclear emergencies. New evaluations of existing tools, past nuclear contamination events and other data sets also welcome.

This session is open to all contributions in biogeochemistry and ecology where stable isotope techniques are used as analytical tools, with a focus on stable isotopes of light elements (C, H, O, N, S, ...). We welcome studies from both terrestrial and aquatic (including marine) environments as well as methodological and experimental, theoretical and modeling studies that introduce new approaches or techniques (including natural abundance work, labeling studies, multi-isotope approaches, clumped and metal isotopes).

Stable isotopes and other novel tracers, such as carbonyl sulfide (COS) and clumped isotopes, help to identify and quantify biological, chemical and physical processes that drive Earth's biogeochemical cycling, atmospheric processes and biosphere-atmosphere exchange. Recent developments in analytical measurement techniques now offer the opportunity to investigate these tracers at unprecedented temporal and spatial resolution and precision.

This session includes contributions from field and laboratory experiments, latest instrument developments as well as theoretical and modelling activities that investigate and use the isotope composition of light elements (C, H, O, N) and their compounds as well as other novel tracers for biogeochemical and atmospheric research.

Topics addressed in this session include:
- Stable isotopes in carbon dioxide (CO2), water (H2O), methane (CH4) and nitrous oxide (N2O)
- Novel tracers and biological analogues, such as COS
- Polyisotopocules ("clumped isotopes")
- Intramolecular stable isotope distributions ("isotopomer abundances")
- Analytical, method and modelling developments
- Flux measurements
- Quantification of isotope effects
- Non-mass dependent isotopic fractionation and related isotope anomalies

Stable isotopes are powerful tools for tracing fluxes of water and associated nutrients in the soil-plant-atmosphere continuum. They are increasingly used by various disciplines to better understand the functioning of the soil-plant-atmosphere system. While new methods allow measurements at high spatial and temporal resolution, studies applying tracer methods are now tackling complex interactions between soil processes, plant physiology and ecology, and variable atmospheric drivers. As such, methodological developments and changes are happening quickly and have a strong bearing on process understanding and interpretation of findings. This session aims to address the current state of the art for methods, applications, and process interpretations using stable isotopes in the critical zone and to foster interdisciplinary exchange. We welcome experimental and modeling studies that present methodological developments and applications of isotope tracers to improve the actual knowledge of the water and nutrient exchanges at the soil-plant-atmosphere interfaces. Studies that seek to cross disciplinary boundaries and reveal new eco-hydrological process understanding are especially welcome.

Land degradation affects more than 52 billion hectares of land around the world. This is caused to a large extent by anthropogenic activities such as land abandonment, mining activities, deforestation, and inadequate land use and management. Disturbance or insufficient rebuilding of the soil physicochemical and biological characteristics can modify the ecosystem functions and services. In the absence of appropriate restoration, soils and ecosystems would remain in a disturbed state or continue to decline. Therefore, restoration and rehabilitation of degraded soils is critical to create healthy and functional ecosystems that support essential functions and services.
In this session, we welcome contributions covering research conducted in this area of research describing experimental, observational, and theoretical studies. Topics of interest are (although not limited to) causes and impacts of land degradation and remedial actions and strategies for soil restoration and rehabilitation at local, regional or global scales.