This open session includes papers dedicated to various aspects of climate research, including but not limited to :
1. Polar regions – climate, oceanography, tectonics, and geohazards
2. Changes and impacts of climate variability in South America
3. Reconstructions of Holocene sea-level changes from high to low latitudes

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 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 community. This session invites work on deep-time climate simulations and proxy-based reconstructions from the Cambrian to the Pliocene. We especially encourage submissions featuring palaeoenvironmental reconstructions, palaeoclimate modelling, and the integration of proxies and models of any complexity.

Reconstructing the climates of past interglacials could improve our understanding and projections of future climate change. Notable examples of past interglacial variability include high sea levels during MIS11c, peak CO2 and CH4 levels during MIS9e and high temperatures over Antarctica during MIS5e. Interestingly, it appears that there is not a single interglacial in the last 800,000 years that experienced the warmest temperatures, the highest sea levels and the most elevated greenhouse-gas concentrations. Moreover, there are substantial differences between interglacials in ocean circulation, sea ice, vegetation, carbon cycle and regional climate. Indeed, when comparing various past interglacials, the variability between them is striking; hence the term interglacial diversity (Tzedakis et al., Nature, 2009). If we want to understand interglacial climate change, we need to understand what causes such diversity.

We therefore invite submissions that explore the characteristics of interglacial diversity. Moreover, we seek to understand the potential drivers of interglacial diversity, for instance insolation changes, the impact of the preceding deglaciation or modes of variability internal to the Earth system. We are particularly interested in new proxy records, compilations of existing data from a range of archives and new theoretical concepts or model experiments that can help to explain the observations. This session will bring together proxy-based, theoretical and/or modelling studies and targets the broader Earth system including changes in climate, ice sheets and the carbon cycle.

The pacing of the global climate system by orbital variations is clearly demonstrated in the timing of e.g. glacial-interglacial cycles. The mechanisms that translate this forcing into geoarchives and climate changes continue to be debated. We invite submissions that explore the climate system response to orbital forcing, and that test the stability of these relationships under different climate regimes or across evolving climate states (e.g. mid Pleistocene transition, Pliocene-Pleistocene transition, Miocene vs Pliocene, and also older climate transitions). Submissions exploring proxy data and/or modelling work are welcomed, as this session aims to bring together proxy-based, theoretical and/or modelling studies focused on global and regional climate responses to astronomical forcing at different time scales in the Phanerozoic.

Polar regions are particularly sensitive to climate variability and play a key role in global climate and environmental conditions through various feedback mechanisms. In this session we invite contributions dealing with all aspects of Phanerozoic (i.e. Cambrian to Holocene) geology from high latitude regions: stratigraphy, paleoenvironment, paleoclimate, and modelling

Ice sheets play an active role in the climate system by amplifying, pacing, and potentially driving global climate change over a wide range of time scales. The impact of interactions between ice sheets and climate include changes in atmospheric and ocean temperatures and circulation, global biogeochemical cycles, the global hydrological cycle, vegetation, sea level, and land-surface albedo, which in turn cause additional feedbacks in the climate system. This session will present data and modelling results that examine ice sheet interactions with other components of the climate system over several time scales. Among other topics, issues to be addressed in this session include ice sheet-climate interactions from glacial-interglacial to millennial and centennial time scales, the role of ice sheets in Cenozoic global cooling and the mid-Pleistocene transition, reconstructions of past ice sheets and sea level, the current and future evolution of the ice sheets, and the role of ice sheets in abrupt climate change.

This session aims to showcase an exciting diversity of state-of-the-art advances in all aspects of Phanerozoic (Cambrian to Quaternary) stratigraphy, paleoceanography, and paleoclimatology. We invite case studies of organic and inorganic geochemistry, sedimentology, and paleontology from marine and terrestrial environments, as well as multidisciplinary and modeling studies. An emphasis is placed upon the use of a variety of tools for deciphering sedimentary records and their stratigraphy across intervals of major environmental change. We further invite contributions that provide insight into the evolution of the Earth on short and long timescales, including climate perturbations and their consequences.

What role did climate dynamics play in human evolution, the dispersal of different Homo species within and beyond the African continent, and key cultural innovations? Were dry spells, stable humid conditions, or rapid climate fluctuations the main driver of human evolution and migration? In order to evaluate the impact that different timescales and magnitudes of climatic shifts might have had on the living conditions of prehistoric humans, we need reliable and continuous reconstructions of paleoenvironmental conditions and fluctuations from the vicinity of paleoanthropological and archaeological sites. The search for the environmental context of human evolution and mobility crucially depends on the interpretation of paleoclimate archives from outcrop geology, lacustrine and marine sediments. Linking archeological data to paleoenvironmental reconstructions and models becomes increasingly important.

As a contribution towards a better understanding of these human-climate interactions the conveners encourage submission of abstracts on their project’s research on (geo)archaeology, paleoecology, paleoclimate, stratigraphy, and paleoenvironmental reconstructions. We especially welcome contributions offering new methods for dealing with difficult archive conditions and dating challenges. We hope this session will appeal to a broad audience by highlighting the latest research on paleoenvironmental reconstructions in the vicinity of key sites of human evolution, showcasing a wide variety of analytical methods, and encouraging collaboration between different research groups. Conceptual models, modelling results and model-data comparisons are warmly welcomed, as collaborative and interdisciplinary research.

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 modelling, all across temporal and spatial scales.

Speleothems and other continental carbonates (e.g. travertines, pedogenic, lacustrine, subglacial and cryogenic carbonates) are important terrestrial archives, which can provide precisely dated, high-resolution records of past environmental and climate changes. The field of carbonate-based paleoclimatology has seen (1) continuously improving analytical capacity, supporting the compilation of detailed records of climate variability integrating established as well as novel and innovative techniques. (2) Long-term environmental monitoring campaigns facilitating the interpretation of high-resolution proxy time series from carbonate archives. (3) The continuous development of proxy-system models that can help understand the measured proxies, by describing processes such as water infiltration, carbonate dissolution, precipitation and diagenesis. (4) The development of proxy databases such as SISAL (Speleothem Isotope Synthesis and AnaLysis) which enable regional-to-global scale analysis of the relationship between the proxy and the environmental parameter using a variety of large data analysis and data-model comparison techniques.

Applied together, advancements in these cornerstones pave the way towards developing highly reliable and quantitative terrestrial climate reconstructions. This session aims to bring together integrated and interdisciplinary studies in order to better understand the precipitation environment of continental carbonates and the incorporation of climate-sensitive proxies at various time scales. We especially invite contributions that show progress in one of the four outlined domains, and welcome speleothem and carbonate-based modern and paleoenvironmental studies, including new records of past climatic changes. 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.

The Sahara is widely recognised as the largest hot desert and the largest single source of mineral dust on the planet. Over the Quaternary it has periodically transformed through natural processes to a vegetated landscape capable of supporting flora and fauna and scattered human populations that are mostly absent today. This remarkable ‘greening’ was driven by variations in Earth’s orbit around the Sun and resultant changes in the hydrological cycle, and was probably maintained by a range of feedbacks in the land-atmosphere-ocean system. Several critical research questions rely on a full understanding of these African Humid Periods (AHPs). For example, it remains to be shown whether the AHPs supported the migration of early hominids out of Africa. AHPs are thought to have terminated abruptly, and so a full characterisation of how these phases evolved is crucial for understanding abrupt climate change dynamics. AHPs also turn out to be a very stringent test of Earth System models (ESMs), with implications for how well ESMs can represent these regions under future conditions.

This session aims to bring together researchers from a range of backgrounds to share and discuss the latest findings around greening events in the Sahara as well as potential links with future climate change. We hope to foster interdisciplinary collaboration and motivate further research in this topic area. We welcome contributions based on archaeological findings, palaeoclimate reconstructions, Earth System modelling or climate theory. Abstracts that combine these fields or that focus on links with present-day and/or future climate in this region are also encouraged.

The half-century since the first deep ice core drilling at Camp Century, Greenland, has seen extensive innovation in methods of ice sample extraction, analysis and interpretation. Ice core sciences include isotopic diffusion analysis, multiple-isotope systematics, trace gases and their isotopic compositions, ice structure and physical properties, high-resolution analysis of major and trace impurities, and studies of DNA and radiochemistry in ice, among many others. Many climate and geochemical proxies have been identified from ice cores, with ongoing effort to extend their application and refine their interpretation. Great challenges remain in the field of ice coring sciences, including the identification of suitable sites for recovery of million-year-old ice; spatial integration of climate records (e.g. PAGES groups Antarctica2k and Iso2k); and deeper understanding of glaciological phenomena such as streaming flow, folding of layers and basal ice properties. This session welcomes all contributions reporting the state-of-the-art in ice coring sciences, including drilling and processing, dating, analytical techniques, results and interpretations of ice core records from polar ice sheets and mid- and low-latitude glaciers, remote and autonomous methods of surveying ice stratigraphy, and related modelling research.

This session aims to place recently observed climate change in a long-term perspective by highlighting the importance of paleoclimate research spanning the past 2000 years. We invite presentations that provide insights into past climate variability, over decadal to millennial timescales, from different paleoclimate archives (ice cores, marine sediments, terrestrial records, historical archives and more). In particular, we are focussing on quantitative temperature and hydroclimate reconstructions, and reconstructions of large-scale modes of climate variability from local to global scales. This session also encourages presentations on the attribution of past climate variability to external drivers or internal climate processes, data syntheses, model-data comparison exercises, proxy system modelling, and novel approaches to producing multi-proxy climate field reconstructions.

Arid to sub-humid regions are home for >40% of the world’s population, and many prehistoric and historic cultures developed in these regions. Due to the high sensitivity of drylands to small-scale environmental changes and anthropogenic activities, ongoing geomorphological processes but also the Late Quaternary geomorphological and palaeoenvironmental evolution as recorded in sediment archives are becoming increasingly relevant for geological, geomorphological, palaeoenvironmental, palaeoclimatic and geoarchaeological research. Dryland research is constantly boosted by technological methodological advances, and especially by emerging linkages with other climatic and geomorphic systems that allow using dryland areas as indicator-regions of global environmental changes.
This session aims to pool contributions that deal with current and former geomorphological processes and environmental changes, as well as with all types of sediment archives in dryland areas (dunes, loess, slope deposits, fluvial sediments, alluvial fans, lake and playa sediments, desert pavements, soils, palaeosols etc.) at different spatial and temporal scales. Besides case studies from individual regions and archives and review studies, methodical and conceptual contributions are especially welcome in this session, e.g. dealing with the special role of aeolian, fluvial, gravitational and biological processes in dryland environments, sediment preservation, methods to obtain chronological frameworks and process rates, emerging geo-technologies and the role of such processes for current and former societies.

The radiation budget of the Earth is a key determinant for the genesis and evolution of climate on our planet and provides the primary energy source for life. Anthropogenic interference with climate occurs first of all through a perturbation of the Earth radiation balance. We invite observational and modelling papers on all aspects of radiation in the climate system. A specific aim of this session is to bring together newly available information on the spatial and temporal variation of radiative and energy fluxes at the surface, within the atmosphere and at the top of atmosphere. This information may be obtained from direct measurements, satellite-derived products, climate modelling as well as process studies. Scales considered may range from local radiation and energy balance studies to continental and global scales. In addition, related studies on the spatial and temporal variation of cloud properties, albedo, water vapour and aerosols, which are essential for our understanding of radiative forcings, feedbacks, and related climate change, are encouraged. Studies focusing on the impact of radiative forcings on the various components of the climate system, such as on the hydrological cycle, on the cryosphere or on the biosphere and related carbon cycle, are also much appreciated.

ENSO and its interactions with other tropical basins are the dominant source of interannual climate variability in the tropics and across the globe. Understanding the dynamics, predictability, and impacts of ENSO and tropical basins interactions, and anticipating their future changes are thus of vital importance for society. This session invites contributions regarding all aspects of ENSO and tropical basins interactions, including: dynamics, multi-scale interactions; low frequency, decadal and paleo variability; theoretical approaches; ENSO diversity; global teleconnections; impacts on climate, society and ecosystems; seasonal forecasting and climate change projections of ENSO and its tropical basins interactions. Studies aimed at evaluating and improving model simulations of ENSO, the tropical mean state and the tropical basins interactions basin are especially welcomed.

Large-scale atmospheric circulation dynamics are the major driver of near surface climatic and environmental variability. Synoptic climatology examines atmospheric circulation dynamics and their relationship with near surface environmental variables. Within synoptic climatological analyses, a wide variety of methods is utilized to characterize atmospheric circulation (e.g., circulation and weather type classifications, regime analysis, teleconnection indices). Various linear and non-linear approaches (e.g., multiple regression, canonical correlation, neural networks) are applied to relate the circulation dynamics to diverse climatic and environmental elements (e.g., air temperature, air pollution, floods).
The session welcomes contributions from the whole field of synoptic climatology. This includes application studies focusing on various regions, time periods and target variables. In particular, we welcome contributions on development and comparison of methods (e.g., varying circulation type classifications) and conceptual approaches (e.g., circulation types versus circulation regimes).

This session explores climate change, extremes, processes and their impacts at local to regional scales, and the tools employed to investigate these phenomena. In particular, we welcome submissions advancing the state-of-the-art in the development and application of high-resolution models (convection-permitting, grid spacing ≤ 4 km) and high-resolution sub-daily data sets. Other high-resolution data sets such as land-surface, vegetation or similar, and their impacts on local-scale climate change and extremes, are of further interest.

The session aims to bring together, amongst others, numerical modellers, the observational community and CORDEX-FPS participants, with the aim of advancing understanding of the aforementioned topics. Of particular interest are any new insights which are revealed through high-spatiotemporal-resolution modelling or data sets. For example: convective extremes, physical mechanisms, fine-scale and feedback processes, differences in climate change signal, scale-dependency of extremes, interactions across scales and land-atmosphere interactions. Further, we welcome studies that explore local-scale climate change in a variety of contexts whether they be past, present or future change.

Additional topics include, though are not limited to:
-- Mesoscale convective systems and medicanes
-- Event-based case studies (including surrogate climate change experiments or attribution)
-- Approaches for quantifying uncertainty at high resolutions including multi-model ensemble and combined dynamical-statistical approaches
-- High-resolution winds and their impacts
-- Convection, energy balance and hydrological cycle including vegetation
-- Model setup and parametrization, including sensitivity to resolution, land surface and dynamics
-- Tropical convection and convective processes at local to regional scale
-- Model evaluation and new evaluation metrics/methods
-- Physical understanding of added value over coarser models
-- Severe storms including supercell thunderstorms and hailstorms
-- The roles of natural and internal variability

Changes in seasonal timing affect species and ecosystem response to environmental change. Observations of plant and animal phenology as well as remote sensing and modeling studies document complex interactions and raise many open questions.
We invite contributions with cross-disciplinary perspectives that address seasonality changes based on recent plant and animal phenological observations, pollen monitoring, historical documentary sources, or seasonality measurements using climate data, remote sensing, flux measurements or modeling studies. Contributions across all spatial and temporal scales are welcome that compare and integrate seasonality changes, study effects of long-term climate change or single extreme events, emphasize applications and phenology informed decision-making, discuss species interactions and decoupling, advance our understanding of how seasonality change affects carbon budgets and atmosphere/biosphere feedbacks, and integrate phenology into Earth System Models.
We emphasize phenology informed applications for decision-making and environmental assessment, public health, agriculture and forest management, mechanistic understanding of the phenological processes, and effects of changing phenology on biomass production and carbon budgets. We also welcome contributions addressing international collaboration and program-building initiatives including citizen science networks and data analyses.

This session is organized by a consortium representing the International Society of Biometeorology (Phenology Commission), the Pan-European Phenology Network - PEP 725, the Swiss Academy of Science SCNAT, the TEMPO French Phenology Network and the USA National Phenology Network.

Observations and model simulations illustrate significant ocean variability and associated air-sea interactions in the tropical Atlantic basin from daily-to-decadal time scales. This session is devoted to the understanding of ocean dynamics in the tropical and subtropical Atlantic Ocean, its interaction with the overlying atmosphere from the equator to the mid-latitudes and its climate impacts on adjacent to remote areas. Relevant processes in the ocean include upper and deep ocean circulation, eddies, tropical instability waves, warm pools, cold tongues and eastern boundary upwellings. We are interested in air-sea interactions related to both the seasonal cycle and the development of modes of variability from local to basin scale (e.g. the Meridional Mode, the Atlantic Niño, and the Benguela Niño). We welcome studies on wind variations related to the development of these modes, as well as studies on high-frequency events, such as marine heat waves, the Madden-Julian Oscillation, tropical cyclones and convective systems. Furthermore, we seek studies on climate change in the region, and also of the climatic impacts of change and variability on marine ecosystems. Finally, we are also interested in contributions examining the causes and impacts of systematic model errors in simulating the local to regional Atlantic climate. Studies based on direct observations, reanalysis, reconstructions as well as model simulations are welcome.

The Indian Ocean is unique among the other tropical ocean basins due to the seasonal reversal of monsoon winds and concurrent ocean currents, lack of steady easterlies that result in a relatively deep thermocline along the equator, low-latitude connection to the neighboring Pacific and a lack of northward heat export due to the Asian continent. These characteristics shape the Indian Ocean’s air-sea interactions, variability, as well as its impacts and predictability in tropical and extratropical regions on (intra)seasonal, interannual, and decadal timescales. They also make the basin particularly vulnerable to anthropogenic climate change, as well as related extreme weather and climate events, and their impacts for surrounding regions, which are home to a third of the global population. Advances have recently been made in our understanding of the Indian Ocean’s circulation, interactions with adjacent ocean basins, and its role in regional and global climate. Nonetheless, significant gaps remain in understanding, observing, modeling, and predicting Indian Ocean variability and change across a range of timescales.

This session invites contributions based on observations, modelling, theory, and palaeo proxy reconstructions in the Indian Ocean that focus on recent observed and projected changes in Indian Ocean physical and biogeochemical properties and their impacts on ecological processes, diversity in Indian Ocean modes of variability (e.g., Indian Ocean Dipole, Indian Ocean Basin Mode, Madden-Julian Oscillation) and their impact on predictions, interactions and exchanges between the Indian Ocean and other ocean basins, as well as links between Indian Ocean variability and monsoon systems across a range of timescales. In particular, we encourage submissions on weather and climate extremes in the Indian Ocean, including marine heatwaves and their ecological impacts. We also welcome contributions that address research on the Indian Ocean grand challenges highlighted in the recent IndOOS Decadal Review, and as formulated by the Climate and Ocean: Variability, Predictability, and Change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), the International Indian Ocean Expedition 2 (IIOE-2), findings informed by the Coupled Model Intercomparison Project version 6 (CMIP6) on past, present and future variability and change in the Indian Ocean climate system, and contributions making use of novel methodologies such as machine learning.

Traditionally, hydrologists focus on the partitioning of precipitation water on the surface, into evaporation and runoff, with these fluxes being the input to their hydrologic models. However, more than half of the evaporation globally comes back as precipitation on land, ignoring an important feedback of the water cycle if the previous focus applied. Land-use and water-use changes, as well as climate variability and change alter, not only, the partitioning of water but also the atmospheric input of water as precipitation, related with this feedback, at both remote and local scales.

This session aims to:
i. investigate the remote and local atmospheric feedbacks from human interventions such as greenhouse gasses, irrigation, deforestation, and reservoirs on the water cycle, precipitation and climate, based on observations and coupled modelling approaches,
ii. investigate the use of hydroclimatic frameworks such as the Budyko framework to understand the human and climate effects on both atmospheric water input and partitioning,
iii. explore the implications of atmospheric feedbacks on the hydrologic cycle for land and water management.

Typically, studies in this session are applied studies using fundamental characteristics of the atmospheric branch of the hydrologic cycle on different scales. These fundamentals include, but are not limited to, atmospheric circulation, humidity, hydroclimate frameworks, residence times, recycling ratios, sources and sinks of atmospheric moisture, energy balance and climatic extremes. Studies may also evaluate different sources of data for atmospheric hydrology and implications for inter-comparison and meta-analysis. For example, observations networks, isotopic studies, conceptual models, Budyko-based hydro climatological assessments, back-trajectories, reanalysis and fully coupled earth system model simulations.

In the current context of global change, assessing the impact of climate variability and changes on hydrological systems and water resources is increasingly crucial for society to better-adapt to future shifts in water resources, as well as extreme conditions (floods and droughts). However, important sources of uncertainty have often been neglected in projecting climate impacts on hydrological systems, especially uncertainties associated with internal/natural climate variability, whose contribution to near-future changes could be as important as forced anthropogenic climate changes at the regional scales. Internal climate modes of variability (e.g. ENSO, NAO, AMO) and their impact on the continent are not always properly reproduced in the current global climate models, leading to large underestimations of decadal climate and hydro-climatic variability at the global scale. At the same time, hydrological response strongly depends on catchment properties, whose interactions with climate variability are little understood at the decadal timescales. These factors altogether significantly reduce our ability to understand long-term hydrological variability and to improve projections and reconstructions of future and past hydrological changes upon which improvement of adaption scenarios depends.

We welcome abstracts capturing recent insights for understanding past or future impacts of large-scale climate variability on hydrological systems and water resources as well as newly developed projection and reconstruction scenarios. Results from model intercomparison studies are encouraged.

Mountains cover approximately one quarter of the total land surface on the planet, and a significant fraction of the world’s population lives in their vicinity. Orography critically affects weather and climate processes at all scales and, in connection with factors such as land-cover heterogeneity, is responsible for high spatial variability in mountain weather and climate. Due to this high complexity, monitoring and modeling the atmosphere and the other components of the climate system in mountain regions is challenging both at short (meteorological) and long (climatological) time-scales. This session is devoted to the better understanding of weather and climate processes in mountain and high-elevation areas around the globe, as well as their modification induced by global environmental change.

We welcome contributions describing the influence of mountains on the atmosphere on meteorological time-scales, including terrain-induced airflow, orographic precipitation, land-atmosphere exchange over mountains, forecasting and predictability of mountain weather.
Contributions connected with the TEAMx research programme (http://www.teamx-programme.org/) are encouraged.

Furthermore, we invite studies that investigate climate processes and climate change in mountain areas and its impacts on dependent systems, based on monitoring and modeling activities. Particularly welcome are contributions that merge various sources of information and reach across disciplinary borders (atmospheric, hydrological, cryospheric, ecological and social sciences) and that connect to the Elevation-Dependent Climate Change (EDCC) working group of the Mountain Research Initiative (see https://www.mountainresearchinitiative.org/activities/community-led-activities/working-groups).

Chemistry and aerosols play a major role in determining surface air quality, the Earth’s energy budget, and climate change. Conversely, climate change affects atmospheric abundances of trace gases and aerosols through composition-climate interactions. This session focuses on global scale atmospheric chemistry and aerosol modelling, radiative forcing, and climate change through the historical period and into the future.
A better understanding of the role of natural aerosols in the atmosphere is essential for assessing climate changes. Our session explores primary aerosols and those formed from precursor gases emitted by natural sources, e.g. from wildfires, deserts, volcanoes, oceans, and vegetation. The session intends to bring together experts from different fields to assess the state-of-the-science knowledge on natural aerosols and to identify future directions to reduce uncertainty in their emissions and impacts. We encourage submissions that use models across different spatial scales and consider past, present or future perspectives, as well as measurements from remote sensing, field campaigns and laboratory experiments.

In particular, it aims to bring together scientists with an interest in:

1. Evaluating reactive gases and aerosols in models against observations

2. Quantifying the impact of emissions changes on atmospheric composition

3. Exploring chemistry-climate interactions in models, with a focus on climate feedbacks involving trace gases and aerosols

4. Quantifying radiative forcing and the climate response to changes in trace gas and aerosol concentrations

5. Distinguishing between truly natural aerosols and those whose emissions or formation are influenced by anthropogenic activities

6. Missing links in our understanding of the lifecycle of natural aerosols

7. The time evolution of contributions of natural aerosols to atmospheric composition and deposition
8. The consequences of changes in natural aerosols


The session welcomes contributions from those currently involved in analysis of recent and ongoing CMIP6 experiments focusing on the areas above,

This session is linked to the Pan-Eurasian EXperiment (PEEX; www.atm.helsinki.fi/peex), a multi-disciplinary, -scale and -component climate change, air quality, environment and research infrastructure and capacity building programme. It is aimed at resolving major uncertainties in Earth system science and global sustainability issues concerning the Arctic, Northern Eurasia and China regions. This session aims to bring together researchers interested in (i) understanding environmental changes effecting in pristine and industrialized Pan-Eurasian environments (system understanding); (ii) determining relevant environmental, climatic, and other processes in Arctic-boreal regions (process understanding); (iii) the further development of the long-term, continuous and comprehensive ground-based, air/seaborne research infrastructures together with satellite data (observation component); (iv) to develop new datasets and archives of the continuous, comprehensive data flows in a joint manner (data component); (v) to implement validated and harmonized data products in models of appropriate spatio-temporal scales and topical focus (modeling component); (vi) to evaluate impact on society though assessment, scenarios, services, innovations and new technologies (society component).
List of topics:
• Ground-based and satellite observations and datasets for atmospheric composition in Northern Eurasia and China
• Impacts on environment, ecosystems, human health due to atmospheric transport, dispersion, deposition and chemical transformations of air pollutants in Arctic-boreal regions
• New approaches and methods on measurements and modelling in Arctic conditions;
• Improvements in natural and anthropogenic emission inventories for Arctic-boreal regions
• Physical, chemical and biological processes in a northern context
• Aerosol formation-growth, aerosol-cloud-climate interactions, radiative forcing, feedbacks in Arctic, Siberia, China;
• Short lived pollutants and climate forcers, permafrost, forest fires effects
• Carbon dioxide and methane, ecosystem carbon cycle
• Socio-economical changes in Northern Eurasia and China regions.
PEEX session is co-organized with the Digital Belt and Road Program (DBAR), abstracts welcome on topics:
• Big Earth Data approaches on facilitating synergy between DBAR activities & PEEX multi-disciplinary regime
• Understanding and remote connection of last decades changes of environment over High Asia and Arctic regions, both land and ocean.

Soil organic matter (SOM) is well known to exert a great influence on physical, chemical, and biological soil properties, thus playing a very important role in agronomic production and environmental quality. Globally SOM represents the largest terrestrial organic C stock, which can have significant impacts on atmospheric CO2 concentrations and thus on climate. The changes in soil organic C content are the result of the balance of inputs and losses, which strongly depends on the processes of organic C stabilization and protection from decomposition in the soil. This session will provide a forum for discussion of recent studies on the transformation, stabilization and sequestration mechanisms of organic C in soils, covering any physical, chemical, and biological aspects related to the selective preservation and formation of recalcitrant organic compounds, occlusion by macro and microaggregation, and chemical interaction with soil mineral particles and metal ions.

To address societal concerns over rising sea level and extreme events, understanding the contributions behind these changes is key to predict potential impacts of sea level change on coastal communities and global economy, and is recognized as one of the Grand Challenges of our time by the World Climate Research Programme (WCRP). To continue this discussion, we welcome contributions from the international sea level community that improve our knowledge of the past and present changes in global and regional sea level, extreme events, and flooding, and produce improved predictions of their future changes.

We welcome studies on various drivers of sea level change and linkages between variability in sea level, heat and freshwater content, ocean dynamics, land subsidence from natural versus anthropogenic influences, and mass exchange between the land and the ocean associated with ice sheet and glacier mass loss and changes in the terrestrial water storage. Studies focusing on future sea level changes are also encouraged, as well as those discussing potential short-, medium-, and long-term impacts on coastal and deltaic environments, as well as the global oceans.

Detecting and attributing anthropogenic climate change in long-term observed climatic trends is an active area of research, seeking to identify ongoing changes in the climate system, and to quantify the contributions of various external forcing to these changes. Attributable trends, as well as a variety of other emerging constraints, can also be used to constrain climate projections. This science is better established for temperature related variables than for other climate indicator including hydrometeorological variables.

Complementary to this, assessing the extent to which extreme weather events, including compound events, are attributable to anthropogenic climate change is a rapidly developing science, with emerging schools of thought on the methodology and framing of such studies. Once again, the attribution of hydrometeorological events, is less straightforward than temperature-related events. The attribution of impacts, both for long-term trends and extreme events is even more challenging.

This session solicits the latest studies from the spectrum of detection and/or attribution approaches. By considering studies over a wide range of temporal and spatial scales we aim to identify common/new methods, current challenges, and avenues for expanding the detection and attribution community. We particularly welcome submissions that compare approaches, address hydrometerological trends, extremes, impacts, and/or assess implications of recent trends in terms of future changes – all of which test the limits of the present science.

This session merges CL3.1.3 “Climate change and other drivers of environmental change: Developments, interlinkages and impacts in regional seas and coastal regions” focused on regional seas and coastal regions worldwide, and CL3.1.4 “Climate change in Mediterranean-type climate regions” focused on the Mediterranean-type climates, with a very similar scope: how climate change and other drivers affect these regions now and in the future.
Regional climate change interacts with many other man-made perturbations in both natural and anthropogenic coastal environments. Regional climate change is one of multiple drivers, which have a continuing impact on terrestrial, aquatic and socio-economic (resp. human) environments. These drivers interact with regional climate change in ways, which are not completely understood.
A Mediterranean-type climate is characterized by mild, wet winters and hot, dry summers as classified with the Koppen-Geiger approach that is well suited for identifying and analyzing the impacts of climate change on natural and anthropic ecosystems. Mediterranean climate regions (MCRs) are located in transitional midlatitude regions like the Mediterranean basin area, western coastal North America and small coastal areas of western South America, southern Africa and southern Australia. The transitional character with sharp spatial gradients makes them highly vulnerable to climate change. For all MCRs, the future holds high risks and uncertainty on issues like loss in biodiversity, increase in aridity, ecological change, requiring innovative approaches to climate adaptation and mitigation.
This session focuses on the connections and interrelations between climate change and other drivers of environmental change in MCRs, regional seas and coastal regions. It intends to strengthen the exchanges among the communities involved to better understand and share commonalities and differences and to provide an overview of the current state of knowledge of the complicated interplay of different factors affecting climate change. This exchange may help identify and prepare shared solutions and practices. Studies focused on physical (including extremes, teleconnections, hydrological cycle) and biogeochemical (including biodiversity) aspects of Mediterranean and other coastal climate regions, focusing on observed past changes, future climate projections, as well as related social aspects including indigenous knowledge in mitigating climate risks will be treated.

The Earth’s subsurface hosts enormous methane volumes trapped in geologic reservoirs, gas hydrates and permafrost, locally escaping the sediment at cold seeps 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.

It becomes increasingly accepted that many regions all over the world are experiencing an increase in the frequency of extreme rainfall events and potentially in their properties. For predicting the impact of future climate change on the landscape, it is therefore vital to understand the dynamics of surface processes under extreme events. Furthermore, focusing on the conditions necessary for extreme events to occur can provide key insights into past changes in climate at different time scales. Extreme storms cause a multitude of hydrogeomorphic and natural hazards responses, including floods and respective fluvial responses, hillslope erosion and failures, and debris flows from slopes into fluvial systems. Measuring, evaluating, and predicting the impacts of extreme rainstorms, however, remains challenging due to the difficult-to-predict and complex nature of storms and rainfall-surface interactions.
This interdisciplinary session focuses on the causative chain which links the deterministic and mostly stochastic nature of the synoptic to meso/regional and watershed scales of extreme storms, to their respective transformation into watershed, slope, and stream hydrology, and to their geomorphic impact. We welcome studies from all the parts of this chain, from all climates, and at all temporal scales, that are focusing on the hydrological responses to extreme events and on their imprints on the landscape through erosion and sediment movement. We favor studies with emphasis on the final noticeable impact of extreme events on the landscape and/or on the integrated long-term consequences of extreme storm regime on landscape evolution. Especially, we encourage studies presenting new physical/stochastic modeling approaches that explicitly investigated the impact of extreme events on the landscape.

As the most evident example of land use and land-cover change, urban areas play a fundamental role in local to large-scale planetary processes, via modification of heat, moisture, and chemical budgets. With rapid urbanization ramping up globally it is essential to recognize the consequences of landscape conversion to the built environment. Given the capability of cities to serve as first responders to global change, considerable efforts are currently being dedicated across many cities to monitor and understand urban atmospheric dynamics and examine various adaptation and mitigation strategies aimed to offset impacts of rapidly expanding urban environments and influences of large-scale greenhouse gas emissions.

This session solicits submissions from both the observational and modelling communities examining urban atmospheric and landscape dynamics, processes and impacts owing to urban-induced climate change, the efficacy of various strategies to reduce such impacts, and techniques highlighting how cities are already using novel science data and products that facilitate planning and policies on urban adaptation to and mitigation of the effects of climate change. Emerging topics including, but not limited to, compounding impacts with urban COVID-19 outbreaks, citizen science and crowdsourcing, or urban-climate informatics, are highly encouraged.

Remaining carbon budgets specify the maximum amount of CO2 that may be emitted while stabilizing warming at a particular level (such as the 1.5 °C target), and are thus of high interest to the public and policymakers. Estimates of the remaining carbon budget comes with associated uncertainties, which are accounted for with various methods. These uncertainties increase in relative terms as more ambitious targets are being considered, or as emission reductions continue to be delayed, making practical implementation of remaining carbon budgets challenging.

This session aims to further our understanding of the climate response under various emission scenarios, with particular interest in emission pathways entailing net-zero targets, 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, that advance our knowledge of remaining carbon budgets and net-zero targets. .

We welcome studies exploring different aspects of climate change in response to future emissions. In addition to studies exploring carbon budgets and the TCRE framework, we welcome contributions on the zero emissions commitment, 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.

Understanding the impact of climate change on natural and socio-economic outcomes plays an important role in informing a range of national and international policies, including energy, agriculture and health. However economic models of (and those designed to include) climate impacts that guide decision makers rely on multiple components, for example projections of future climate change, damage functions, and policy responses, each of which comes with its own modelling challenges and uncertainties.

We invite research using process-based (e.g., Integrated Assessment Models) and empirical models of climate change to investigate future human and natural impacts, together with policy evaluation to explore effective mitigation, technology and adaptation pathways. Furthermore, we invite research on changes to, and new developments of climate-economic and econometric modelling.

In 2015, the UN Sustainable Development Goals and the Paris Agreement on climate recognized 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 and interactions between the carbon cycle, the atmosphere, oceans, large-scale ecosystems, and the cryosphere, as well as the dynamics and perturbations associated with human activities.

With rising anthropogenic pressures, there is an increasing risk we might be hitting the ceiling of some of the self-regulating feedbacks of the Earth System, and cross tipping points which could trigger large-scale and partly irreversible impacts on the environment, and impact the livelihood of millions of people. Potential domino effects or tipping cascades could arise due to the interactions between these tipping elements and lead to a further decline of Earth resilience. At the same time, there is growing evidence supporting the potential of positive (social) tipping points that could propel rapid decarbonization and transformative change towards global sustainability.

In this session we invite contributions on all topics relating to tipping points in the Earth system, positive (social) tipping, as well as their interaction and domino effects. We are particularly interested in various methodological approaches, from Earth system modelling to conceptual modelling and data analysis of nonlinearities, tipping points and abrupt shifts in the Earth system.

Agriculture is an important sector of any economy of the world. Agriculture productions are highly dependent on the climate change and variability. Changes in hydro-meteorological variables can influence crop yield and productivity at many places. Further, climate change can influence nutrient levels, soil moisture, water availability and other terrestrial parameters related to the agricultural productivity. Changes in the frequency and severity of droughts and floods could pose challenges for farmers and ranchers and threaten food safety. Further, changes in climate can influence meteorological conditions and thus can influence the crop growth pattern. It may also influence irrigation scheduling and water demand of the crops. The effects of climate change also need to be considered along with other evolving factors that affect agricultural production, such as changes in farming practices and technology.

The purpose of the proposed session is to gather scientific researchers related to this topic aiming to highlight ongoing researches and new applications in the field of climate change and agriculture. In this framework, original works concerned with the development or exploitation of advanced techniques for understanding the impact of climate change on agriculture will be invited.

The conveners of this session will encourage both applied and theoretical research in this area.

Extreme climate and weather events, associated disasters and emergent risks are becoming increasingly critical in the context of global environmental change and interact with other stressors. 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.
This session explores the linkages between extreme climate and weather events, 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?
We welcome empirical, theoretical and modelling studies from local to global scale from the fields of natural sciences, social sciences, humanities and related disciplines.

With recent extreme events reaching far beyond existing records, such as the Pacific Northwest heat wave and severe flooding in Western Europe, eastern US and across China, the discussion to what extent we are prepared for unprecedented extremes and whether existing methods and models are able to capture them has flared up. It is becoming increasingly essential to understand and quantify plausible rare, high-impact events for risk management and adaptation.
Methods to understand and evaluate low-likelihood extreme events have seen substantial advancements over the recent years. Event attribution studies are now providing rapid analyses of unprecedented extreme events; physical climate storylines are developed to evaluate plausible rather than likely events; causal inference is used to understand drivers of very rare events; near-miss events and potential analogues in space, historical and paleo archives are evaluated; spatial extreme value analysis and machine learning methods are applied, large ensembles representing various outcomes are generated, such as Single Model Initial-condition Large Ensembles (SMILEs); and weather prediction systems are increasingly being employed, such as the through the UNprecedented Simulated Extremes using ENsembles (UNSEEN) approach.
This session aims to bring together communities from weather prediction, climate projection, hydrology to impact and risk management, and to learn from the variety of methods to understand and quantify low-likelihood extreme events in the present and future climate. The session welcomes contributions at all temporal and spatial scales, and all types of extremes and invites novel methods – including downward counterfactuals and causal inference – as well as new results on unforeseen climate risks – including those from compound events and low-likelihood high-warming outcomes.

Climate change is debated most often for its environmental and socioeconomic repercussions; however, it also has a dramatic impact on tangible cultural heritage worldwide. The safeguard and fruition of cultural assets – outdoors or indoors, and either on land, underground, or underwater – are jeopardized by the current and expected environmental changes. The behavior of the component materials varies likewise, in response to global warming, sea level rise, ocean acidification, and the increase of extreme weather events.
This session addresses the climate change risk to cultural heritage from the interdisciplinary perspective of geosciences, which represent a valuable support for investigating the properties and durability of the materials (e.g., stones, ceramics, mortars, pigments, glasses, and metals); their vulnerability and the changes in weathering dynamics; the key environmental variables (pertaining to climate, microclimate, air pollution, water and soil composition) and the effects of extreme events; the techniques and products to improve conservation practices; and the adaptation measures for heritage protection. This session welcomes contributions based on approaches including but not limited to field and laboratory analysis and testing; damage assessments and simulations; modelling of risk scenarios and decay trends; strategies of monitoring and remote investigation; and processing of environmental databases.

The current scientific consensus links climate change to devastating consequences for society including natural hazards, heatwaves, floods, droughts and hurricanes. Yet, potential solutions requiring collaboration between communities, local actors and scientists continue to face considerable structural, spatial, temporal and definitional challenges.
Structural challenges: Political and micro-political aspects and how they interact with structural inequalities are important to understand vulnerability and the disproportionate impacts of climate change induced extreme events.
Spatial challenges: At the local level, providing usable information for people is challenging particularly in the poorest regions of the world. While hazards can be explored with weather and climate data. overall risk can only be assessed by balancing location-specific information and data which is often inaccessible or under researched.
Temporal challenge: Often climate change impacts have not been monitored consistently or according to the best available science and data. Particularly in the global South and developing economies, these temporal challenges make effective adaptation challenging.
Definitional challenge: vulnerability across time-space is defined in diverse ways. Many approaches tend to use hazard, exposure and vulnerability interchangeably. Whereas the assessment of local vulnerability is only possible by combining natural and social sciences with stakeholder engagement, prevailing interventions miss one or the other resulting in limited possibility for project sustainability Furthermore, a universal conceptualization or approach to vulnerability is yet to be presented.
Local adaptation solutions to these challenges do exist and could be used as models to be transferred to other regions. For example, UNESCO-designated sites such as Biosphere Reserves and UNESCO Global Geoparks provide solutions for climate change mitigation and adaptation based on inclusive, transparent, and empowering governance processes, in line with sustainable development.
We welcome research on locally produced and scientifically robust solutions to these structural, spatial, temporal and definitional challenges. Particularly abstracts focusing on 1) the quantification of hazards, risks, and impacts that matter for the identified community, 2) conceptual frameworks and tools to assess vulnerability and exposure, 3) approaches to monitor impacts and 4) case studies that showcase local solutions.

This session investigates mid-latitude cyclones and storms on both hemispheres. We invite studies considering cyclones in different stages of their life cycles from the initial development, to large- and synoptic-scale conditions influencing their growth to a severe storm, up to their dissipation and related socioeconomic impacts.
Papers are welcome, which focus also on the diagnostic of observed past and recent trends, as well as on future storm development under changed climate conditions. This will include storm predictability studies on different scales. Finally, the session will also invite studies investigating impacts related to storms: Papers are welcome dealing with vulnerability, diagnostics of sensitive social and infrastructural categories and affected areas of risk for property damages. Which risk transfer mechanisms are currently used, depending on insured and economic losses? Which mechanisms (e.g. new reinsurance products) are already implemented or will be developed in order to adapt to future loss expectations?

Hydroclimatic conditions and availability of water resources in space and time constitute important factors for maintaining adequate food supply, the quality of the environment, and the welfare of citizens and inhabitants, in the context of a post-pandemic sustainable growth and economic development. This session is designed to explore the impacts of hydroclimatic variability, climate change, and temporal and spatial availability of water resources on different factors, such as food production, population health, environment quality, and local ecosystem welfare.
We particularly welcome submissions on the following topics:
• Complex inter-linkages between hydroclimatic conditions, food production, and population health, including: extreme weather events, surface and subsurface water resources, surface temperatures, and their impacts on food security, livelihoods, and water- and food-borne illnesses in urban and rural environments.
• Quantitative assessment of surface-water and groundwater resources, and their contribution to agricultural system and ecosystem statuses.
• Spatiotemporal modeling of the availability of water resources, flooding, droughts, and climate change, in the context of water quality and usage for food production, agricultural irrigation, and health impacts over a wide range of spatiotemporal scales.
• Smart infrastructure for water usage, reduction of water losses, irrigation, environmental and ecological health monitoring, such as development of advanced sensors, remote sensing, data collection, and associated modeling approaches.
• Modelling tools for organizing integrated solutions for water supply, precision agriculture, ecosystem health monitoring, and characterization of environmental conditions.
• Water re-allocation and treatment for agricultural, environmental, and health related purposes.
• Impact assessment of water-related natural disasters, and anthropogenic forcing (e.g. inappropriate agricultural practices, and land usage) on the natural environment (e.g. health impacts from water and air, fragmentation of habitats, etc.)

Fire is an essential feature of terrestrial ecosystems and an important component of the Earth system. Climate, vegetation, and human activity regulate fire occurrence and spread, but fires also feedback to them in multiple ways. This session welcomes contributions that explore the role of fire in the Earth system at any temporal and spatial scale using modeling, field and laboratory observations, proxy-records, and/or remote sensing. We encourage all abstracts that advance our understanding on interactions between fire and (1) weather, climate, as well as atmospheric chemistry and circulation, (2) biogeochemical, energy, and water cycles, (3) vegetation composition and structure, (4) pyrogenic carbon, including effects on soil functioning and soil organic matter dynamics, (5) cryosphere (e.g. permafrost, sea ice), and (6) humans (e.g., impact of fire on air and water quality, freshwater resources, human health, land use and land cover change, fire management). We also welcome contributions focusing on fire characterization, including (7) fire behavior and emissions (e.g. fire duration, emission factors, emission height, smoke transport), (8) spatial and temporal changes of fire regimes in the past, present, and future, (9) fire products and models, and their validation, error/bias assessment and correction, and (10) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems.

Climate change (CC) and ocean degradation (OD) are among the greatest threats to humanity. Climate impacts the ocean in massive ways; the ocean is the climate’s most powerful regulator. Separately or combined, they impact every living being and ecological niche, with poorer communities suffering disproportionately. In turn, flora and fauna (incl humans) are suffering. CC and OD are affecting the cryosphere, biodiversity, and food and water security. Given that humans are the prime cause of this devastating change taking us beyond our planetary boundaries, geoethical issues come to the fore.

The 2020 EGU Declaration of the Significance of Geoscience highlights the need for massive and widespread action to help people around the world to become literate about the changes affecting their and their offsprings’ and communities’ lives. The more people are literate about these changes, the more they can make informed decisions, adapt and mitigate. Previous General Assemblies have addressed climate change literacy (CL). Ocean literacy (OL) has developed strongly in recent years, especially with impetus from the UN Ocean Decade. Ocean-climate literacy (OCL) is an imperative that needs to be addressed massively and urgently, both within and beyond the EGU.

We invite colleagues to submit contributions on any aspects of OCL; this can, of course, include CL (without the ocean) and OL (without the climate). We welcome papers related, eg, to learning processes/experiences, instructional materials, curricular innovation, learning games, citizen initiatives, Ocean Decade activities, evaluation, well-used methods, novel approaches and policies, eg, 1. make OCL an essential component in all subjects and at all levels of education; 2. require all people in positions of responsibility (eg, mayors, teachers, doctors, CEOs, ministers, et al) to pass exams on the basics of climate and/or ocean before taking office. Of particular interest are literacy actions that bring in geoethical dimensions. (If your paper is primarily on geoethics, then a better home is the EGU session on geoethics.) The broad aims of such OCL might include encouraging an intergenerational outlook, developing a sense of the geoethical dimensions of OCL, understanding complexities and implementing solutions.

This session is an opportunity for ECSs, scientists, educators, policy influencers, learning resource developers and other practitioners to share their experience, expertise and research on CL and OL.

This session aims to share innovative approaches to developing multi-hazard risk assessments and their components (hazard, exposure, vulnerability and capacity), and to explore their applications to disaster risk reduction.

Effective disaster risk reduction practices and the planning of resilient communities requires the evaluation of multiple hazards and their interactions. This approach is endorsed by the UN Sendai Framework for Disaster Risk Reduction. Multi-hazard risk and multi-hazard impact assessments look at interaction mechanisms among different natural hazards, and how spatial and temporal overlap of hazards influences the exposure and vulnerability of elements at risk. Moreover, the uncertainty associated with multi-hazard risk scenarios needs to be considered, particularly in the context of climate change and slow-onset hazards, such as Covid-19 and pandemics in general, characterized by dynamic changes in exposure and vulnerability that are challenging to quantify.

This session, therefore, aims to profile a diverse range of multi-hazard risk and impact approaches, including hazard interactions, multi-vulnerability studies, and multi-hazard exposure characterization. In covering the whole risk assessment chain, we propose that it will be easier to identify potential research gaps, synergies and opportunities for future collaborations.

We encourage abstracts which present innovative research, case study examples and commentary throughout the whole disaster risk cycle on (i) multi-hazard risk methodologies which address multi-vulnerability and multi-impact aspects; (ii) methodologies and tools for multi-hazard risk management and inclusive risk-informed decision making and planning; (iii) methodologies and tools for multi-hazard disaster scenario definition and management for (near) real-time applications; (iv) cross-sectoral approaches to multi-hazard risk, incorporating the physical, social, economic, and/or environmental dimensions; (v) uncertainty in multi-hazard risk and multi-hazard impact assessment; (vi) evaluation of multi-hazard risk under future climate and slow-onset hazards, including pandemics; (vii) implementation of disaster risk reduction measures within a multi-hazard perspective.

Climate impact and adaptation research has made considerable progress in various fields in the recent years. However, the concrete implementation on the ground needs to be improved.
Local decision makers are facing several challenges with regard to climate adaptation. At the center of this process lies the coupling of climate, impact and risk (incl. vulnerability) models in order to identify future climate risk levels. Finding and correctly using the necessary data in climate impacts and risks assessments and planning for climate action is not without challenges for specialists from other fields.
While climate modelling and technical integration of diverse model data are crucial, social science as well as interdisciplinary perspectives are essential to assess local adaptation capacities, the costs and benefits of adaptive measures and to ensure the usability and transferability of the climate services. Similarly important is capacity building and trainings on properly using, interpreting and communicating climate and impact information.
This session touches upon innovative ways to address theses challenges. It also supports exchange on experiences in impact and adaptation studies, using all kinds of climate data. Former participants from the C3S ULS and IS-ENES3 training events are particularly encouraged to join.
This session discusses approaches and challenges towards the support of climate change adaptation and disaster risk reduction. Central to the discussion is the question how such services can be developed in a stringent co-design process that integrates different natural and social science disciplines as well as users and practitioners. We are therefore seeking for contributions that discuss:
• Actionable services for regional decision-making in regional climate adaptation and disaster risk reduction and challenges in the interaction between researchers and decision makers
• New scientific insights into regional climate and impact modelling (data interfaces and harmonization)
• Assessing local climate adaptation capacities and measures in an integrated way
• New insights into transdisciplinary processes in climate change adaptation
• Data availability for climate impact studies and methods for dealing with limited data availability as well as the opposite, a large number of seemingly similar datasets.
• Experiences with existing tools or newly developed tools for data processing

Global warming is unequivocal: the frequency and intensity of heavy precipitation events increased since the mid-20th century in all regions in which observational data were sufficient for trend analysis. And heavy precipitations and related effects are projected to intensify and be more frequent in most regions.
In this framework, particular attention should be paid to all the ground events triggered by rainfall, among which landslides and soil erosion.
Changes in temperature also have been shown to affect the hydraulic and mechanical behavior of soils and rocks in multiple ways, suggesting the importance of monitoring and modelling thermal variables alongside the hydraulic ones.
The influence of climate variables on the triggering, frequency, and severity of slope failures and soil erosion can be different according to the area, the time horizon of interest, and the specific trends of weather variables. Similarly, land use/cover change can play a pivotal role in exacerbating or reducing such hazards.
Thus, the overall impacts depend on the region, spatial scale, time frame, and socio-economic context addressed. However, even the simple identification of the weather patterns regulating the occurrence of such phenomena represents a not trivial issue, also assuming steady conditions, due to the crucial role played by geomorphological details. To support hazards’ monitoring, predictions, and projections, last-generation and updated datasets with high spatio-temporal resolution and quality - as those from the Copernicus Services’ Portals - are useful to feed models, big-data analytics, and indicators’ frameworks enabling timely, robust, and efficient decision making.
The Session aims at presenting studies concerning ongoing to future analysis on the impact of climate change on landslide triggering and dynamics, and soil erosion hazard, across different geographical contexts and scales. Either investigations including analyses of historical records and related climate variables, or modeling approaches driven by future climate exploiting downscaled output of climate projections are welcome. Studies assessing variations in severity, frequency, and/or timing of events and consequent risks are valuable.
Moreover, a focus on all aspects of landslide thermo-hydro-mechanics, from experimental studies to field and remote-sensing monitoring, from microstructural analyses to geomechanical modelling at various spatial and temporal scales, is proposed.

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.

Citizen science (the involvement of the public in scientific processes) is gaining momentum across multiple disciplines, increasing multi-scale data production on Earth Sciences that is extending the frontiers of knowledge. Successful participatory science enterprises and citizen observatories can potentially be scaled-up in order to contribute to larger policy strategies and actions (e.g. the European Earth Observation monitoring systems), for example to be integrated in GEOSS and Copernicus. Making credible contributions to science can empower citizens to actively participate as citizen stewards in decision making, helping to bridge scientific disciplines and promote vibrant, liveable and sustainable environments for inhabitants across rural and urban localities.
Often, citizen science is seen in the context of Open Science, which is a broad movement embracing Open Data, Open Technology, Open Access, Open Educational Resources, Open Source, Open Methodology, and Open Peer Review. Before 2003, the term Open Access was related only to free access to peer-reviewed literature (e.g., Budapest Open Access Initiative, 2002). In 2003 and during the “Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities”, the definition was considered to have a wider scope that includes raw research data, metadata, source materials, and scholarly multimedia material. Increasingly, access to research data has become a core issue in the advance of science. Both open science and citizen science pose great challenges for researchers to facilitate effective participatory science, yet they are of critical importance to modern research and decision-makers.

We want to ask and find answers to the following questions:
Which approaches and tools can be used in Earth and planetary observation?
What are the biggest challenges in bridging between scientific disciplines and how to overcome them?
What kind of participatory citizen scientist involvement (e.g. how are citizen scientists involved in research, which kind of groups are involved) and open science strategies exist?
How to ensure transparency in project results and analyses?
What kind of critical perspectives on the limitations, challenges, and ethical considerations exist?
How can citizen science and open science approaches and initiatives be supported on different levels (e.g. institutional, organizational, national)?