Union-wide
Community-led
Inter- and Transdisciplinary Sessions
Disciplinary sessions

CR – Cryospheric Sciences

Programme Group Chair: Carleen Tijm-Reijmer

CR1 – The State of the Cryosphere: Past, Present, Future

Sub-Programme Group Scientific Officers: Daniel Farinotti, Maaike Izeboud

CR1.1 EDI

Glaciers and ice caps are major contributors to sea-level rise and have large impacts on runoff from glacierized basins. Major mass losses of glaciers and ice caps have been reported around the globe for the recent decades. This is a general session on glaciers outside the Greenland and Antarctic ice sheets, emphasizing their past, present and future responses to climate change. Although much progress in understanding the link between glaciers and climate and the impacts of their wastage on various systems has recently been achieved, many substantial unknowns remain. It is necessary to acquire more direct observations, both applying novel measurement technologies and releasing unpublished data from previous years, as well as combining in situ observations with new remote sensing products and modelling. In order to improve our understanding of the processes behind the observed glacier changes, the application of models of different complexity in combination with new data sets is crucial. We welcome contributions on all aspects of glacier changes – current, past and future – based on field observations, remote sensing and modelling. Studies on the physical processes controlling all components of glacier mass balance are especially encouraged, as well as assessments of the impact of retreating glaciers and ice caps on sea-level rise, runoff and other downstream systems.

Convener: Lander Van TrichtECSECS | Co-conveners: Harry Zekollari, Ines Dussaillant, Lindsey Nicholson
CR1.2 EDI | PICO

The increasing availability of remotely sensed observations and computational capacity, drive modelling and observational glacier studies towards increasingly large spatial scales. These large scales are of particular relevance, as they impact policy decisions and public discourse. Glacier play a key role in current sea-level contribution, in seasonal water availability, in the susceptibility to natural hazards or for touristic activities. To tackle the spatial challenge, AI informed techniques became of particular interest in terms of computational feasibility both for data analysis and model forecasting.

This session focuses on advances in observing and modelling mountain glaciers and ice caps at the regional to global scale. We invite both observation- and modelling-based contributions, which may include, but are not limited to the following topics:
• comparative studies of glacier evolution across single or multiple mountain ranges
• glacier-related impact studies on sea-level contribution, mountain hazards, mountain hydrology, etc.
• advances in large-scale monitoring
(e.g., AI-supported monitoring, multi-sensor homogenisation, meta-analysis of ground-based data, process inferences)
• advances in large-scale modelling
(e.g., reconciling AI with classical approaches, including physical processes, model coupling to others subsystems, improving strategies for data assimilation, refining climatic downscaling)
• regional to global-scale data products and scalable modelling frameworks

Convener: Johannes J. Fürst | Co-conveners: Lilian Schuster, Fanny Brun, Martina Barandun, Fabien Maussion
CR1.3 EDI

Process understanding is crucial in assessing the sensitivity of glacier systems to changing climate. Comprehensive glacier monitoring provides the base for large-scale glacier distribution and change assessment. Glaciers are observed on different spatio-temporal scales, from extensive seasonal mass-balance studies at individual glaciers to decadal assessments of glacier mass changes and repeat inventories at the scale of entire mountain ranges. Internationally coordinated glacier monitoring combines in-situ measurement with remotely sensed data and local process understanding with global coverage. We invite contributions from various disciplines, from tropical to polar glaciers, addressing both in-situ and remotely sensed monitoring of past and current glacier distribution and changes, as well as related uncertainty assessments.

In the International Year of Glaciers' Preservation 2025, this session shall have a particular focus on (i) the achievements of long-term glacier monitoring from in-situ and remotely sensed observations, (ii) the intercomparison of results from different observation methods, and (iii) the advance of glacier inventories towards change assessments at regional to global scale.

Convener: Michael Zemp | Co-conveners: Livia Jakob, Fanny Brun, Roberto Dinale
CR1.4 EDI

The evolution of glaciers, ice caps, and ice sheets can have a profound impact on the Earth system. For example, during the Quaternary, ice sheet growth and decay resulted in the fluctuation of sea levels, alteration of global air and ocean circulation patterns, sculpting of the landscape, and reorganisation of continental drainage. Landforms and sediments provide important information about the dimensions, distribution, and dynamics of past ice sheets. This record can be used to understand ice dynamics, reconstruct climate, and refine our understanding of the future response of ice masses to variations in climate. The aim of this session is to bring together researchers focused on reconstructing past glaciations at all spatial scales and from all parts of the world. We welcome studies of all relevant aspects, for example (i) glacial landforms and sediments, (ii) glacial reconstructions and chronologies, (iii) glaciologic and climatic interpretations, and (iv) numerical modelling. While the focus of the session will be Quaternary glaciations, studies from any geological period are encouraged to fully address the diversity of the topic.

Co-organized by GM9
Convener: Benjamin BoyesECSECS | Co-conveners: Rosie Archer, Helen Dulfer, Martin Margold, Danni Pearce
CR1.5 EDI

The East Antarctic Ice Sheet (EAIS) contains the vast majority of Earth’s glacier ice (around 52 metres sea-level equivalent) but is often viewed as less vulnerable to global warming than the West Antarctic or Greenland ice sheets. Recent estimates indicate that the EAIS is broadly in balance, with some marine-based catchments losing mass, whilst others appear to be gaining mass due to increased accumulation. Of concern, however, is that some marine-based sectors that are currently losing mass are thought to have undergone significant retreat during past warm periods such as the Mid-Pliocene, Marine Isotope Stage 11 and potentially as recently as the Last Interglacial (Marine Isotope Stage 5e). These catchments, such as the Wilkes and Aurora Subglacial Basins, are vulnerable to ocean warming and are close to critical locations for the oceanic overturning circulation. Furthermore, model predictions suggest that the melting of the ice sheet grounded over these catchments could contribute several metres to global mean sea-level rise over the next few centuries under medium to high emissions scenarios, despite local increased accumulation. The global impact of mass loss from East Antarctica’s marine basins is thus significant but our understanding of the sensitivity of this important component of the Earth system is hampered by a sparsity of observations, both past and present. This session aims to bring people working on palaeo-records and modern observations of the EAIS together with those using numerical modelling to: (i) facilitate greater interaction between these communities; (ii) highlight recent progress, and (iii) identify and co-ordinate efforts for future research. We solicit contributions from those working on terrestrial and offshore records of palaeo-ice sheet and palaeo-circulation change, together with those working on modern observations of EAIS dynamics, ice shelves and mass balance, as well as those using ice sheet modelling across a range of timescales from past, present, and future. Contributions on ice sheet-ocean interactions, including sea ice, and on impact of past ice sheet changes on ecosystems are also strongly encouraged.

Convener: Jennifer ArthurECSECS | Co-conveners: Chris R. Stokes, Laura De Santis, Nancy Bertler
CR1.6 EDI

This session seeks to bring together studies from the fields of glaciology, glacial geomorphology and geology, geochronology, climatology, remote sensing, and environmental history to provide a comprehensive overview of the current state of science on Little Ice Age (LIA) glacier advances.
LIA advances have been documented in many of the world’s glaciated regions between roughly 1300 and 1900 CE, although the timing of these advances varies regionally.
The extent and variations of glaciers during the LIA are of major significance because they offer a unique snapshot of the “natural”, pre-industrial state of the cryosphere, before the global climate and environmental disruption caused by human activity since the beginning of the industrial era.
We invite contributions that examine any aspect of LIA glacier advances, ranging from studies aiming to reconstruct the timing and climatic conditions of these advances to those aiming to assess LIA glacier extent, ice thickness as well as post LIA glacier change, or studies on their societal impacts, such as the effects they had on local mountain communities. We welcome presentations employing diverse methods and data sources, including dating, remote sensing, or modelling approaches, and using satellite, instrumental, historical, and geomorphological records.
We hope that this session can help identify key knowledge gaps regarding LIA glacier advances and provide a road map to guide future research priorities and efforts in this field.

Co-organized by GM9
Convener: Paul WeberECSECS | Co-conveners: Samuel U. Nussbaumer, Liss M. Andreassen, Jörg Franke, Clare Boston
CR1.7

Climate change has a significant impact on the amount, spatial and temporal distribution of the cryosphere (snow, glaciers, permafrost), and associated water resources in different regions of the world. Several studies show that the response of the cryosphere to climate change is not only an effect of temperature change, but depends on several factors such as geographical location (climate zone), latitude and regional atmospheric forcing (e.g. interaction with synoptic-scale atmospheric currents), among others. However, observational capacity and process understanding of these interactions vary considerably within and between regions. For example, despite the importance of snow in mountainous regions, a comprehensive global inventory of mountain snow based on robust data is still lacking. Filling this research gap is one of the main motivations for the Joint Body “Status of Snow Cover in Mountain Regions”, a joint effort of IACS, WMO and the MRI.

The aim of the session is to bring together the knowledge and experience of researchers from and working in different regions of the world (e.g. mountains, and polar regions, such as theArctic) working on similar topics related to climate-induced changes in the cryosphere. An expected outcome of the session is therefore to take stock and present the current state of knowledge and to identify research gaps that may be useful for future work. Given the overall importance of the cryosphere for ecology, economy and human life in general, researchers from different and also interdisciplinary fields are invited to contribute, for all regions of the world and using a variety of data sources and analytical methods (including modelling experiments, in situ observations, satellite products or reanalysis data).

Convener: Wolfgang Schöner | Co-conveners: Marcelo Somos-Valenzuela, Carolina Adler, Lijuan Ma, Elias J. Deeb
CL1.2.9 EDI

The Greenland Ice Sheet (GrIS) is losing mass at a fast pace and is currently the largest single contributor to global sea level rise. The IPCC projects a sea level rise of 0.28-1.01 meters by 2100, of which between 0.01 to 0.18 meters isexpected from GrIS. However, these estimations exclude possible severe ice-sheet instability scenarios. Recent observations of record-high temperatures, accelerated ice melt, and increased freshwater flux, accentuate the risk of overstepping tipping points in GrIS which may destabilize ocean circulation, affect weather patterns, and increase sea level beyond current predictions.
Therefore, a better constraint on the past extent and variability of the GrIS is needed to improve our understanding of its observed and projected response to changes in climate forcing.
We therefore would like to invite contributions aiming on:
1) Analysing the ice margin’s retreat and recovery in response to temperature changes, determining whether this response is linear or non-linear.
2) Identifying the ocean-climate conditions that led to near-complete deglaciation of the GrIS in the past.
3) Assessing the timing and sequence of interactions between the GrIS and polar climate over annual to decadal periods
Topics will include, but not be limited to: multi-proxy data on ice-ocean interactions, such as iceberg production and meltwater fluxes, ice core and sediment archive analyses to assess ice sheet and climate variability across past warmer-than-present climates, studies that investigate Greenland Ice Sheet variability during anomalously warm periods of the Pleistocene and Pliocene, as well as climate/ice sheet model simulations relating past and future response of the Greenland ice sheet to a warmer climate.
This session aims to foster interdisciplinary discussions and collaborations, bringing together proxy records as well as climate and ice sheet models.
The session is supported by the Danish NNF PRECISE, the ERC synergy grant Green2Ice as well as several projects funded by H2020 and Horizon Europe.

Co-organized by CR1
Convener: Kasia K. Sliwinska | Co-conveners: Helle Astrid Kjær, Matteo Willeit, Lara F. Pérez, Paul Knutz

CR2 – lce sheets, ice shelves and glaciers

Sub-Programme Group Scientific Officers: Daniel Farinotti, Maaike Izeboud

CR2.1 EDI

This session is intended to attract a broad range of ice-sheet and glacier modelling contributions, welcoming applied and theoretical contributions. Theoretical topics that are encouraged are higher-order mechanical models, data inversion and assimilation, representation of other earth sub-systems in ice-sheet models, and the incorporation of basal processes and novel constitutive relationships in these models.
Applications of newer modelling themes to ice-sheets and glaciers past and present are particularly encouraged, in particular those considering ice streams, rapid change, grounding line motion and ice-sheet model intercomparisons.

Convener: Sainan Sun | Co-conveners: Fabien Gillet-Chaulet, Mauro Werder, Rabea Sondershaus, Brad Reed
CR2.2 EDI

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.

Co-organized by CL4/NP3/OS1
Convener: Heiko Goelzer | Co-conveners: Ronja Reese, Jonas Van Breedam, Alexander Robinson
CR2.3 EDI

Dynamic subglacial, supraglacial and englacial water networks play a key role in the flow and stability of glaciers and ice sheets. The accumulation of meltwater on the surface of ice shelves has been hypothesized as a potential mechanism controlling ice-shelf stability, with ice-shelf collapse triggering substantial increases in discharge of grounded ice. Observations and modelling also suggest that complex hydrological networks occur at the base of glaciers and ice sheets and these systems play a prominent role in controlling the flow of grounded ice. This session tackles the urgent need to better understand the fundamental processes involved in glacial hydrology that need to be addressed in order to accurately predict future ice-sheet evolution and mass loss, and ultimately the contribution to sea-level rise.

We seek contributions from both the modelling and observational communities relating to any area of ice-sheet, ice-shelf, or glacier hydrology. This includes but is not limited to: surface hydrology, melt lake and river formation; meltwater processes within the ice and firn; basal hydrology; subglacial lakes; impacts of meltwater on ice-sheet stability and flow; incorporation of any of these processes into large-scale climate and ice-sheet models.

Co-organized by HS13
Convener: Sammie Buzzard | Co-conveners: Alison Banwell, Riley Culberg, Amber Leeson, Gabriela Clara Racz
CR2.4 EDI

Ice shelves and tidewater glaciers are sensitive elements of the climate system. Sandwiched between atmosphere and ocean, they are vulnerable to changes in either. The recent disintegration of ice shelves such as Larsen B and Wilkins on the Antarctic Peninsula, current thinning of the ice shelves in the Amundsen Sea sector of West Antarctica, and the recent accelerations of many of Greenland's tidewater glaciers provide evidence of the rapidity with which those systems can respond. Changes in marine-terminating outlets appear to be intimately linked with acceleration and thinning of the ice sheets inland of the grounding line, with immediate consequences for global sea level. Studies of the dynamics and structure of the ice sheets' marine termini and their interactions with atmosphere and ocean are the key to improving our understanding of their response to climate forcing and of their buttressing role for ice streams. The main themes of this session are the dynamics of ice shelves and tidewater glaciers and their interaction with the ocean, atmosphere and the inland ice, including grounding line dynamics. The session includes studies on related processes such as calving, ice fracture, rifting and mass balance, as well as theoretical descriptions of mechanical and thermodynamic processes. We seek contributions both from numerical modelling of ice shelves and tidewater glaciers, including their oceanic and atmospheric environments, and from observational studies of those systems, including glaciological and oceanographic field measurements, as well as remote sensing and laboratory studies.

Co-organized by OS1
Convener: Ronja ReeseECSECS | Co-conveners: Nicolas Jourdain, Rachel Carr, Peter Washam
CR2.5 EDI

Oceans are an important interface between the cryosphere and the global climate system, both due to the ocean’s ability to impact ice sheet mass balance and the cryosphere’s influence on global ocean circulation. Processes at the ice-ocean interface play a crucial role to the dynamics of tidewater glaciers and ice shelves, and associated fjord and cavity circulation. However, a complete understanding and accurate representation of these processes in models remains a major challenge and a source of uncertainty for projections of ice mass loss and sea-level rise. Recent work to understand ice-ocean interactions has led to significant progress in theory, idealised models, and coupled ice-ocean models. New observations of processes such as seawater intrusion at grounding lines and channelised ice-shelf melting can provide further insights into our understanding of this important climate interface. These continued efforts are essential to improving projections of future sea-level rise contributions from the Earth’s cryosphere under climate change.

In this session we aim to bring together the most up to date work on ice-ocean interactions, covering in-situ observations, remote-sensing, modelling and theory. We seek a bi-directional perspective, investigating both the impact of the ocean on the cryosphere and vice-versa. Topics for submission include, but are not limited to: coupled ice-ocean models, ice shelf cavity and fjord circulation, ice melange, subglacial meltwater plumes, basal and submarine melting and freshwater fluxes into the ocean. New observational datasets and methodologies are encouraged.

We welcome and encourage submissions from groups who are underrepresented in the cryosphere community and will endeavour to provide reasonable adjustments to any presenter who requires them.

Co-organized by OS1
Convener: Benjamin WallisECSECS | Co-conveners: Joanna Zanker, Shenjie Zhou, Donald Slater, Irena Vankova
CR2.6 EDI

The interaction between fjord waters and marine-terminating glaciers is a key component of Polar glaciological, oceanographic and ecological systems. When glaciers discharge ice, meltwater and sediments into fjords, the salinity, density and temperature of the fjord water change impacting the fjord circulation, nutrient fluxes and the ecosystem dynamics. Likewise, fjord conditions, such as temperature and salinity, impact glacier dynamics, affecting calving front behaviour, grounding line stability and subglacial melting. These interactions can accelerate glacier retreat or enhance melt. Thus, glacier-fjord processes are key to understanding how glaciers influence the polar marine environment ultimately impacting human livelihoods.
The fjord-ice interface is characterised by a range of complex processes operating at different spatial and temporal scales, that are not easily captured in large-scale models used for climate projections. Similarly, observations from the inaccessible polar environment remain limited, particularly outside the summer season leading to biased observational evidence and a poor understanding of wintertime ice-fjord dynamics.
This session aims to bring together observational and process studies, numerical modelling efforts and impact assessments. We welcome contributions addressing any or all aspects of glacier-fjord interactions such as ocean boundaries, fjord circulation, nutrient fluxes, ice/ocean parameterisations, glacier front dynamics, calving processes, atmospheric effects, impacts on ecosystems and societal consequences. We aim to bring together scientists working across all latitudes ranging from the high Arctic to the Antarctic including the glacier systems of Svalbard, Alaska and Patagonia.

Co-organized by OS1
Convener: Nanna Bjørnholt Karlsson | Co-conveners: Anneke Vries, Faezeh M. Nick, William D. Harcourt, Andrew Wells
CR2.7 EDI

The investigation of interactions between ice sheets and the solid Earth has facilitated notable advancements in comprehending the cryosphere's response to climate variability. The growing volume of geological and geophysical data collected from Greenland, Antarctica, and other continental ice/snow-covered areas (such as the Alps, Andes, and High Mountains of Asia) has provided a more detailed understanding of the subglacial environment.
Nevertheless, the connections between subglacial boundary conditions and the behavior of ice sheets, ice shelves, and snow cover in the past, present, and future remain elusive, and their integration into numerical modeling frameworks could be enhanced.
This session aims to consolidate research that deepens our knowledge of the interactions between the solid Earth and the overlying ice sheets, shelves, and glaciers through the use of remote sensing, airborne, ground-based, and time-lapse measurements. Key boundary conditions of interest include, but are not limited to, subglacial topography, sub-ice shelf bathymetry, geothermal heat flux, subglacial geology, basal sediment and water distribution, and ice thickness estimation, including studies on the Snow Water Equivalent. We also welcome studies assessing uncertainty quantification in geophysical problems and/or focused on addressing significant geological and geophysical data gaps in the continental shelf or inland regions.

Convener: Renata Constantino | Co-conveners: Matthew Tankersley, Carla Braitenberg, Guy Paxman, Jonathan Kingslake
CR2.8

Geological materials such as ice and olivine are often modelled as viscous fluids at the large scale. However, they have complex, evolving microstructures which are not present in normal fluids, and these can have a significant impact on large-scale flow behaviour. These different materials have many commonalities in how the evolving microstructure influences the large scale flow, yet research is often siloed into individual disciplines.

With this session, we aim to bring together researchers from a range of disciplines, studying a variety of anisotropic materials, and working on different aspects of complex viscous flow such as: viscous anisotropy related to CPO or extrinsic microstructures; crystallographic preferred orientation (CPO) or fabric evolution; other controls on rheology such as grain size, dynamic recrystallisation and deformation mechanisms; and impact of rheology on complex flow, e.g. in the transition through a shear margin.

We encourage submissions investigating this topic through numerical modelling, laboratory experiments and observational studies. We are aiming to convene an inclusive and collaborative session, and invite contributions from all disciplines. We particularly encourage early career researchers to participate.

Co-organized by GD7/TS1
Convener: Daniel RichardsECSECS | Co-conveners: Lisa Craw, Ágnes Király, Nicholas Rathmann
HS2.1.1 EDI

Water stored in the snowpack and in glaciers represents an important component of the hydrological budget in many regions of the world, as well as a sustainment to life during dry seasons. Predicted impacts of climate change in catchments covered by snow or glaciers (including a shift from snowfall to rainfall, a modified total amount of precipitation, an earlier snowmelt, and a decrease in peak snow accumulation) will reflect on water resources availability for environment and anthropogenic uses at multiple scales. This may have potential implications for energy, drinking water and food production, as well as for environmentally targeted water management.

The generation of runoff in catchments that are impacted by snow or ice profoundly differs from rainfed catchments. And yet, our knowledge of snow/ice accumulation and melt patterns and their impact on runoff is highly uncertain, because of both limited availability and inherently high spatial variability of hydrological and weather data in such areas.

Contributions addressing the following topics (but not limited to) are welcome:
- Experimental research on snowmelt & ice-melt runoff processes and potential implementation in hydrological models;
- Development of novel strategies for snowmelt runoff modelling in various (or changing) climatic and land-cover conditions;
- Evaluation of remote-sensing or in-situ snow products and application for snowmelt runoff calibration, data assimilation, streamflow forecasting or snow and ice physical properties quantification;
- Observational and modelling studies that shed new light on hydrological processes in glacier-covered catchments, e.g. impacts of glacier retreat on water resources and water storage dynamics or the application of techniques for tracing water flow paths;
- Studies addressing the impact of climate change and/or extreme events (e.g., droughts) on the water cycle of snow and ice affected catchments.
- Studies on cryosphere-influenced mountain hydrology and water balance of snow/ice-dominated mountain regions;
- Use of modelling to propose snowpack, snowmelt, icepack, ice melt or runoff time series reconstruction or reanalysis over long periods to fill data gaps;

Co-organized by CR2
Convener: Francesco Avanzi | Co-conveners: Giulia Mazzotti, Doris Duethmann, Abror Gafurov, Guillaume Thirel
OS1.7 EDI

The interaction between the ocean and the cryosphere in the Southern Ocean has become a major focus in climate research. Antarctic climate change has captured public attention, which has spawned a number of research questions, such as: Is Antarctic sea ice becoming more vulnerable in a changing climate? Where and when will ocean-driven melting of ice shelves yield a tipping point in the Antarctic climate? What drives the observed reduction in Antarctic Bottom Water production? How does the Antarctic Slope Current interact with the continental shelf? What role do ice-related processes play in nutrient upwelling on the continental shelf and in triggering carbon export to deep waters? Are we seeing a new state for Antarctic sea ice? If so, what ice shelf, sea-ice, ocean and atmospheric processes play roles in determining this new state?

Recent advances in observational technology, data coverage, and modeling provide scientists with a better understanding of the mechanisms involving ice-ocean interactions in the far South. Processes on the Antarctic continental shelf have been identified as missing links between the cryosphere, the global atmosphere and the deep open ocean that need to be captured in large-scale and global model simulations.
This session calls for studies on physical and biogeochemical oceanography linked to ice shelves and sea ice. This includes work on all scales, from local to basin-scale to circumpolar; as well as paleo, present-day and future applications. Studies based on in-situ observations, remote sensing and regional to global models are welcome. We particularly invite cross-disciplinary topics involving glaciology, sea ice physics and biological oceanography.

Co-organized by CR2
Convener: Xylar Asay-Davis | Co-conveners: Valentina Volkova, Maren Elisabeth Richter, Torge Martin

CR3 – Sea, Lake and River Ice

Sub-Programme Group Scientific Officers: Kirsty Langley, Luisa von Albedyll

CR3.1

Retrieving sea, lake and river ice information is important for modelling weather and climate changes, and understanding ecological dynamics and the planet's response to anthropogenic forcing. Understanding ice conditions is also important for local indigenous communities, and for wider economic, logistical, and operational activities, such as navigation, tourism and freight transport.

The recent decade has seen an exponential increase in the collection and availability of remote sensing data pertaining to sea, lake and river ice conditions. Extracting meaningful information and developing data products at scale derived from remote sensing necessitates digital technologies for the storage, preparation, collation and analysis of these big datasets, such as AI or other high-performance computing techniques.

This session welcomes contributions utilising techniques such as segmentation, detection, forecasting, resolution enhancement, data infilling and data fusion that provide novel insights into sea, lake or river ice. Submissions are particularly encouraged that push the boundaries of the spatiotemporal resolution of the ingested data or improve on existing data products, as well as those that enable new advancements in AI or other techniques providing emerging insights into ice conditions.

Furthermore, this session aims to integrate sea, lake or river ice experts with AI and model specialists to exchange new knowledge in algorithm development regarding ice information retrieval.

Convener: Andreas StokholmECSECS | Co-convener: Martin Rogers
CR3.2 EDI

In recent years, sea ice has displayed behaviour previously unseen in the satellite record. This fast-changing sea-ice cover calls for adapting and improving our modelling approaches and mathematical techniques to simulate its behaviour and its interaction with the atmosphere and the ocean, both in terms of dynamics and thermodynamics.

Sea ice is governed by a variety of small-scale processes that affect its large-scale evolution. Modelling this nonlinear coupled multidimensional system remains a major challenge, because (1) we still lack the understanding of the physics governing sea-ice dynamics and thermodynamics, (2) observations to conduct model evaluation are scarce and (3) the numerical approximation and the simulation become more difficult and computationally expensive at higher resolution.

Recently, several new modelling approaches have been developed and refined to address these issues. These include but are not limited to new rheologies, discrete element models, advanced subgrid parameterizations, the representation of wave-ice interactions, sophisticated data assimilation schemes, often with the integration of machine learning techniques. Moreover, novel in-situ observations and the growing availability and quality of sea-ice remote-sensing data bring new opportunities for improving sea-ice models.

This session aims to bring together researchers working on the development of sea-ice models, from small to large scales and for a wide range of applications such as idealised experiments, operational predictions, or climate simulations, to discuss current advances and challenges ahead.

Co-organized by NP1/OS1
Convener: Lorenzo ZampieriECSECS | Co-conveners: Clara Burgard, Carolin Mehlmann, Einar Örn Ólason, Lettie Roach
CR3.3 EDI

Significant reductions in Arctic sea ice extent, concentration and thickness have been consistently witnessed during the last decades. Whilst Antarctic sea ice extent was remarkably stable until 2016/2017, this has changed over recent years with 2022 to 2024 producing the lowest three minimum Antarctic sea ice extents on record. 2023 and 2024 have been particularly stark due to the lack of recovery of the sea ice cover, raising concerns for the future of Antarctic sea ice. Climate projections suggest a continued reduction of the sea ice cover for both poles, with the Arctic becoming seasonally ice free in the latter half of this century.

The scientific community is investing considerable effort in organising our current knowledge of the physical and biogeochemical properties of sea ice, exploring poorly understood sea ice processes, and forecasting future changes of the sea ice cover, such as in CMIP6.

In this session, we invite contributions regarding all aspects of sea ice science and sea ice-climate interactions in both the Arctic and Southern Ocean, including snow and sea ice thermodynamics and dynamics, sea ice-atmosphere and sea ice-ocean interactions, sea ice biological and chemical processes, sea ice observational and field studies and models. A focus on emerging processes and implications is particularly welcome.

Convener: Adam BatesonECSECS | Co-conveners: Daniela Flocco, Srikanth Toppaladoddi, Gaelle Veyssiere, Daniel Feltham
OS1.1 EDI

The Arctic region has undergone drastic changes over the last decades, with sea ice decline being the most obvious and prominent example. The ice cover has become thinner and more fragile, drifting faster and more freely. Extreme temperatures are now more common, with 2023 recording the warmest summer temperatures ever. The Arctic has warmed nearly four times faster than the rest of the world, accelerating ice sheet melting, sea ice loss in the Kara and Laptev Seas, permafrost thawing, glacier retreat, and forest fires. The resulting changes in the Arctic Ocean include an increased freshwater volume, heightened coastal runoff from Siberia and Greenland, and greater exchanges with the Atlantic and Pacific Oceans, all of which have significant consequences for the fragile Arctic ecosystems.

As global temperatures continue to rise, model projections suggest that the Arctic Ocean could become seasonally ice-free by mid-century, raising critical questions for the Arctic research community: What could the Arctic Ocean look like in the future? How will the present changes in the Arctic affect and be affected by the lower latitudes? Which oceanic processes drive this sea-ice loss and how will they change in a sea ice-free Arctic? What aspects of the changing Arctic should observational, remote sensing and modeling programs prioritize?

In this session, we invite contributions from a variety of studies on the recent past, present and future Arctic. We welcome submissions that explore interactions between the ocean, atmosphere, and sea ice; Arctic processes and feedbacks; small-scale processes, internal waves, and mixing; and the interactions between the Arctic and global oceans. We especially welcome submissions that take a cross-disciplinary approach, focusing on new oceanic, cryospheric, and biogeochemical processes as well as their connections to land.

We want to spark discussions on future plans for Arctic Ocean measurement, remote sensing, and modeling strategies, including the upcoming CMIP7 cycle and ways to validate and improve models using observations. We encourage submissions on CMIP modeling approaches and recent observational programs like MOSAiC, the Nansen Legacy Project and the Synoptic Arctic Survey. We also welcome anyone involved in planning the upcoming International Polar Year 2032-33 to participate in our session and contribute to the discussions.

Co-organized by CL5/CR3
Convener: Vasco MüllerECSECS | Co-conveners: Stefanie Rynders, Yufang Ye, Rafael S. Reiss, Zoé Koenig

CR4 – Frozen ground, debris-covered glaciers and geomorphology

Sub-Programme Group Scientific Officers: Carleen Tijm-Reijmer, Lindsey Nicholson

CR4.1 EDI

Permafrost temperature, active layer thickness and rock glacier velocity are recognized as Essential Climate Variables for permafrost within the framework of the Global Observing Monitoring Systems. These parameters are critical to understanding the impacts of climate warming, especially in Earth’s high-latitude and high-altitude regions. Long-term monitoring and analysis of these variables provide insights into the changes occurring due to global temperature increases. The organisation and maintenance of such datasets is the core mission of the Global Terrestrial Network for Permafrost (GTN-P) and the Rock Glacier Inventories and Kinematics (RGIK) Standing Committees of International Permafrost Association. This session aims to foster discussion on the latest developments and research in permafrost monitoring. We invite presentations that cover: a) Results from long-term monitoring of permafrost temperature, active layer thickness and rock glacier velocity; b) The integration of observational data for comprehensive regional and global assessments of permafrost and rock glacier changes; c) The use of GTN-P data for validation, assimilation into models, and development of reanalysis products for Earth System Models; d) The integration of remote sensing applications in permafrost and rock glacier monitoring. This session will provide an essential platform for sharing advancements in permafrost research, discussing the importance of sustained observation, and exploring new strategies for integrating data to improve climate models and projections.

Co-sponsored by IPA
Convener: Filip Hrbáček | Co-conveners: Cécile Pellet, Anna Irrgang, Dmitry Streletskiy
CR4.2 EDI

Recent studies show widespread warming of permafrost and indicate that the Arctic has warmed up to four times faster than the global average. Increasing temperatures initiate a wide range of landscape and environmental changes, including vegetation changes, changing hydrological and fire regimes, as well as abrupt and gradual permafrost thaw. Interdisciplinary efforts are needed to further investigate developments in Arctic, boreal, and high-latitude permafrost regions and to better understand the processes and impacts of ongoing changes.
This session is intended as a forum for scientists involved in state-of-the-art research on permafrost disturbance dynamics, associated processes, and impacts. We welcome contributions concerning studies on different scales, from local studies including, but not limited, to field observations, near-surface geophysics, and drone measurements, to regional and circumpolar analyses supported by modelling approaches and remote sensing techniques. We encourage submissions targeted at dynamic permafrost disturbance processes and their feedback to climate across Arctic-boreal, high-mountain, and coastal regions, including, e.g., thermokarst, coastal erosion, anthropogenic impacts, hydrology, mass movements, sediment fluxes, and biogeochemical cycling and associated fluxes.
This session seeks abstracts on (1) novel observations of permafrost disturbance-related phenomena; (2) the impact of permafrost changes on the natural and human environment; and (3) advances and new developments in the measurement, modelling, parametrization, and understanding of permafrost-related processes.
We particularly encourage contributions that (a) identify novel processes related to permafrost disturbances and environmental changes in permafrost regions; (b) present novel measurement and monitoring approaches; (c) outline new strategies to improve process understanding; (d) come from or interface with neighbouring fields of science or apply innovative technologies and methods; (e) investigate model validation, model uncertainty, and scaling issues; and (f) land surface models of diverse processes or scales.

Convener: Helena BergstedtECSECS | Co-conveners: Rodrigo Correa Rangel, Victor Brovkin, Mark Schlutow, Judith Vogt
CR4.3 EDI

Permafrost, which underlies approximately 15% of the northern hemisphere land surface, profoundly influences subsurface hydrology, the partitioning of surface and subsurface water, and mass transport processes in cold regions. Changes in climate and permafrost are therefore associated with perturbations and reconfigurations of these hydrologic systems, which has, for example, been observed as increaseses in connectivity between subsurface and surface water systems and concomitant changes in biogeochemical cycles and mass transport. Our current understanding of these interacting changes has advanced rapidly in recent years, due to technical innovations and new data stemming from inter-disciplinary fields.

For this session, we aim to bring together research that integrates understanding of the processes controlling surface and subsurface hydrology, biogeochemistry, and mass transport in permafrost regions. We welcome contributions from field-, laboratory-, remote sensing-, and modelling-based research from the cold regions of the world, focusing on a wide range of time and spatial scales. Studies on basic process understanding and those on impacts and interactions with human and other natural systems are all welcome.

Convener: Ylva Sjöberg | Co-conveners: Wolfram Rühaak, Élise Devoie, Jeffrey McKenzie, John Molson
CR4.4 EDI

Climate change significantly affects high mountain regions by strongly altering the cryosphere. It influences landscapes, water resources, slope stability, ecosystem balances, and human/touristic activities, all closely interconnected and interdependent. Permafrost degradation remains often hidden but has the potential (1) to destabilize mountain slopes, leading to large-scale landslides or rock-ice avalanches, (2) to mobilize large amounts of loose materials, generating sudden and destructive debris flows, and (3) to cause ground subsidence, with adverse effects on infrastructure. These and other mixed cascading effects illustrate the sensitivity of mountain permafrost systems and the importance of closely monitoring and understanding them.

This session welcomes all contributions from mountain permafrost research in all periglacial environments: from high Arctic climates through any continental regions (e.g. Alpine, Andean, Tibetan) to arid unglaciated areas of Antarctica. We welcome a broad spectrum of ice-rich and ice-poor landforms, including rock glaciers, talus slopes, plateaus, ice-cored moraines, steep rock slopes, and thermokarst. We particularly encourage contributions that enhance understanding thermo-hydro-mechanical-chemical processes at slope and regional scales. The combination of multiple methods and newly developed approaches is of particular interest, as well as long-term studies or characterization of new permafrost sites with state-of-the-art methods. Geophysical measurements and analysis (e.g., ERT, SRT, DAS, EM, IP, GPR, TLS), in-situ measurements (e.g., temperatures, discharge, kinematics, GNSS), remote sensing surveys (e.g., optical, thermal, InSAR, UAV), modeling from past to future processes and scenarios, early warning systems, and data analysis improvements thanks to machine learning and artificial intelligence tools can be submitted.

We aim to improve the understanding of the response of mountain permafrost to climate change. This session aims to create a new opportunity for meeting and exchange within the mountain permafrost community and its fellows to promote joint research developments and improve understanding of processes.

ECS are encouraged to submit their work to this session.

Convener: Samuel Weber | Co-conveners: Theresa Maierhofer, Jacopo Boaga, Coline Mollaret
CR4.5 EDI

Permafrost in the High Mountain Asia (HMA) region is experiencing rapid degradation under climate change with profound and widespread implications, including increasing risks to ecosystem health, infrastructure stability and compounding climate disasters. Furthermore, understanding the relationship between permafrost degradation and associated geohazards due to slope instability, such as landslides, debris flows, avalanches, and glacial lake outburst floods, is crucial for risk assessment and mitigation.
This session invites research on the monitoring and modeling permafrost dynamics in this critical region. We seek contributions that explore the latest techniques/approaches for monitoring, assessing and forecasting permafrost dynamics using ground-based measurements, multi-sensor and multi-scale remote sensing, modeling and geophysical methods. We also highly encourage submissions investigating the linkages between permafrost and hazards, feedbacks and their potential impacts on local communities and infrastructure in the HMA.
The session also aims to foster discussions on early warning and forecasting systems, Disaster Risk Reduction (DRR) and sustainable development pathways in the context of permafrost change. Contributions focused on policy-relevant research and integrating scientific knowledge into decision-making processes are highly encouraged. By sharing knowledge and fostering collaboration, this session seeks to advance our understanding of permafrost dynamics in HMA and contribute to building a sustainable future for the region.

Convener: Debmita BandyopadhyayECSECS | Co-conveners: Remya S N, Tobias Bolch, Maximillian Van Wyk de Vries
GM9.5

Rock glaciers are characteristic landforms associated with mountainous periglacial landscapes and generated by gravity-driven creep of (ice-rich) frozen ground (permafrost). Their location, characteristics and evolution are controlled by a combination of environmental (e.g. internal structure, topography, lithology, debris loading) and climate-dependent factors (e.g. thermal and hydrological regimes). Rock glaciers are highly relevant in various fields of research, such as geomorphology, hydrology, geohazards, paleo-permafrost and climate impact studies. Despite their significance, their complex interactions with environmental variables and the impact of climate change on their evolution remain incompletely understood.

In this open session, we welcome contributions from the entire rock glacier community reflecting the different focuses and ranging from observations to modelling, from geophysical to remote sensing methodologies, from site-specific to regional studies in diverse geographic regions of the World. We would especially like to stimulate discussions about innovative methodologies and interdisciplinary approaches, aiming to improve the understanding of past and/or present processes and to assess future rock glacier evolution.

Co-organized by CR4
Convener: Diego Cusicanqui | Co-conveners: Cécile PelletECSECS, Lea Hartl, Line Rouyet
GM9.4 EDI

Glaciers cover roughly 10 percent of the Earth’s surface and help shape landscapes and relief in high latitude regions and many mountain ranges. Subglacial processes, such as sliding, create material that shapes the landscape. Paraglacial processes also have a strong impact on the glacial landscape evolution. Debris that falls upon the ice, or is entrained it in, is advected down glacier to where it melts out, creating moraines. Existing sediment below the glacier can be mobilized by pressurized subglacial water and is then transported in proglacial rivers or deposited in lakes or fjords. The role and importance of these processes will evolve as glacier dynamics change and hydrology in glacierized catchments responds to climate change.
This session aims at gathering contributions that use modeling, laboratory, field observations and archives or remote sensing methods, or a combination thereof, to evaluate these processes. We welcome submissions that address these processes across a wide range of timescales, from sub-daily to multi-millennial, including those focused on these dynamics during past climate variations. Additionally, we are interested in research contributions focused on diverse glaciated environments from small alpine glaciers to ice sheets. Research that addresses the changes that occur as climate warms and how these processes interact with other aspects of the Earth system, including glacier dynamics, is of particular interest for this session.

Co-organized by CR4
Convener: Jingtao LaiECSECS | Co-conveners: Audrey Margirier, Ian Delaney, Kai Cao

CR5 – Snow and ice: properties, processes, hazards

Sub-Programme Group Scientific Officers: Daniel Farinotti, Cristina Pérez-Guillén

CR5.1

Snow cover characteristics (e.g., spatial distribution, surface and internal physical properties) are continuously evolving over a wide range of scales due to meteorological conditions, such as precipitation, wind, and radiation.
Most processes occurring in the snow cover depend on the vertical and horizontal distribution of its physical properties, which are primarily controlled by the microstructure of snow (e.g., density and specific surface area). In turn, snow metamorphism changes the microstructure, leading to feedback loops that affect the snow cover on coarser scales. This can have far-reaching implications for a wide range of applications, including snow hydrology, weather forecasting, climate modelling, avalanche hazard forecasting, and the remote sensing of snow. The characterization of snow thus demands synergetic investigations of the hierarchy of processes across the scales, ranging from explicit microstructure-based studies to sub-grid parameterizations for unresolved processes in large-scale phenomena (e.g., albedo and drifting snow).
This session is therefore devoted to modelling and measuring snow processes across scales. The aim is to gather researchers from various disciplines to share their expertise on snow processes in seasonal and perennial snowpacks. We invite contributions ranging from “small” scales, as encountered in microstructure studies, over “intermediate” scales typically relevant for 1D snowpack models, up to “coarse” scales, that typically emerge for spatially distributed modelling over mountainous or polar snow- and ice-covered regions. Specifically, we welcome contributions reporting results from field, laboratory, and numerical studies of the physical and chemical evolution of snowpacks. We also welcome contributions reporting statistical or dynamic downscaling methods of atmospheric driving data, assimilation of in-situ and remotely sensed observations, representation of sub-grid processes in coarse-scale models, and evaluation of model performance and associated uncertainties.

Co-organized by AS1/HS13
Convener: Benjamin Walter | Co-conveners: Nora Helbig, Richard L.H. Essery, Neige Calonne, Christopher Marsh
CR5.2 EDI

Although snow may evoke pleasant childhood memories for many, it can also pose various hazards. Some common hazards associated with snowfall and accumulation include (1) disruption of traffic lines due to snow accumulations or bad visibility, (2) damage to infrastructure, such as buildings or power lines, from snow loads or snow creep, (3) flooding due to rapid snowmelt and rain-on-snow events, and (4) snow avalanches that can damage infrastructure or cause loss of life. In all these cases, the presence and accumulation of snow are key factors contributing to the hazards, and it is essential to recognize the impact these hazards can have, to better predict their occurrence and mitigate their risks.
The aim of this session is thus to improve our understanding of processes responsible for snow and avalanche hazards and share solutions to monitor and mitigate their impact. We welcome contributions from novel field, laboratory, and numerical studies as well as specific case studies. Topics relevant to snow and avalanche hazards include, but are not limited to, monitoring and predicting snowfall, drifting or blowing snow, meteorological driving factors, snow cover simulations, snow mechanics, avalanche formation and dynamics, avalanche forecasting, and risk mitigation measures such as technical protection measures or nature-based solutions like protective forests.

Convener: Cristina Pérez-Guillén | Co-conveners: Alec van Herwijnen, Anselm Köhler, Michaela Teich, Ingrid Reiweger
CR5.3 EDI

Plastic pollution affects every ecosystem of the planet. It has been shown that tiny plastic particles (defined as microplastics when they reach a size of 5 mm or below), especially those of low density, can be transported through the air over distances up to several thousands of kilometres, reaching even the most remote regions. High mountain ranges and the poles are no exception, where microplastics can eventually deposit through wet (rainfall, snowfall) or dry deposition. The UN Nations has declared 2025 as the International Year of Glaciers' Preservation, with the aim to protect these sensitive ecosystems from the effects of global threats, mainly from the current climate change. Microplastics could pose an added climatic threat to these ecosystems. Similar to other snow impurities, such as mineral dust or black carbon, plastic particles have the potential to absorb solar radiation, eventually decreasing snow albedo. They could further yield economic losses in certain areas that rely on these ecosystems for basic needs or recreational activities.

In this session, we welcome contributions from field, laboratory and modelling studies reporting plastic (including macro-, meso- micro- and nanoplastic) pollution in the Cryosphere, or their potential impacts in the short and long-term. Studies can include, but are not limited to:
• Sampling and analysis of micro- and nanoplastics in polar and non-polar cryospheric regions,
• New sampling or analytical techniques aimed to standardisation;
• Approaches to determine potential sources of plastic pollution to these areas;
• The interaction between atmospheric micro- and nano-plastic and the Cryosphere
• Plastic degradation studies;
• Studies reporting changes in the physical properties of snow related to plastic pollution;
• Biological impacts of plastics in the cryosphere;
• Socio-economic impacts of plastics in cryospheric regions;
• Mitigation strategies to reduce plastic pollution.

Convener: Isabel Marín BeltránECSECS | Co-conveners: Roberto Ambrosini, J. Ignacio López-Moreno, Sophia Mützel
CL4.14 EDI | PICO

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

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

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

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

Co-organized by AS3/BG1/CR5/GM6
Convener: Jan-Berend Stuut | Co-conveners: Claire Ryder, Clarissa Baldo, Martina Klose
HS6.3 EDI | PICO

Snow constitutes a freshwater resource for over a billion people worldwide. A high percentage of this water resource mainly comes from seasonal snow. The ongoing warming poses a significant risk to snow water storages, potentially leading to a drastic reduction in water supply and causing adverse effects on the ecosystems.
Therefore, understanding seasonal snow dynamics, possible changes, and implications have become crucial for water resources management.

Remote sensing technology plays a crucial role in monitoring snow properties and their hydrological implications across spatial and temporal scales, allowing for a better understanding of snow dynamics (e.g., the interaction of snow with small-scale, quick snow changes within a day, rain on snow events, snow-vegetation interaction).

This session focuses on studies linking the use of remote sensing of seasonal snow to hydrological applications to: (i) quantify snow characteristics (e.g., SWE, snow grain size, albedo, pollution load, snow cover area, snow depth and snow density), (ii) understand and model snow-related processes and dynamics (snowfall, melting, evaporation, wind redistribution and sublimation), (iii) assess snow hydrological impacts and snow environmental effects. Works including technique and data from different technologies (time-lapse imagery, laser scanners, radar, optical photography, thermal and hyperspectral technologies, or other new applications) across spatial (from the plot to the global) and temporal (from instantaneous to multiyear) scales are welcome.

Co-organized by CR5
Convener: Ilaria Clemenzi | Co-conveners: César Deschamps-Berger, Rafael Pimentel, Claudia Notarnicola

CR6 – Instrumental and paleo-archive observations, analyses and data methodologies in the cryospheric sciences

Sub-Programme Group Scientific Officers: Lindsey Nicholson, Luisa von Albedyll

CR6.1 EDI

We are heading towards a climate state that has not been observed through human-made measurements before, making information on past climatic states increasingly important for anticipating future Earth System changes. Presently, sea ice is rapidly declining, and it plays a crucial role in the climate system, with proxy evidence suggesting its involvement in abrupt climate shifts.

In this session, we invite studies of past climates that aim to advance the understanding of sea ice processes and associated climate changes, thereby enhancing or constraining cutting-edge climate models. We are particularly interested in studies focusing on interglacials and warm periods, as well as other periods of climatic interest. Contributions that explore both colder and warmer-than-modern climate states are particularly encouraged.

We welcome:
-Studies that refine existing records or generate new time series from ice, terrestrial, and marine cores, including sea ice proxies such as IP25 or IPSO25 in marine cores, and Bromine, Iodine, MSA, water isotopes, and sea salt sodium from ice cores.
-Investigations into sea ice as both a driver and responder to high-frequency climate variability, with data from both polar oceans exploring Antarctic and Arctic sea ice extent alongside co-recorded climate feedbacks.
-Proxy evidence of past sea ice spatial and temporal changes.
-Both proxy and model studies that link past sea ice changes with other climatic processes, such as temperature changes, moisture source variations, or major ocean state changes like AMOC.

This session aims to bring together research on past sea ice dynamics during both colder and warmer-than-modern climate states, enhancing our understanding of sea ice processes and their role in climate systems. By refining existing records and generating new data, we seek to improve climate models and our ability to predict future changes. Join us in contributing to this critical area of research at EGU2025.

Co-organized by CL1.2
Convener: Helle Astrid Kjær | Co-conveners: Erin McClymont, Andrea Spolaor, Louise Sime, Kasia K. Sliwinska
CR6.2 EDI | PICO

Earth’s cryosphere demonstrates itself in many shapes and forms, but we use similar geophysical and in-situ methods to study its wide spectrum: from ice-sheets and glaciers, to firn and snow, sea ice, permafrost, and en-glacial and subglacial environments.
In this session, we welcome contributions related to all methods in cryospheric measurements, including: advances in radioglaciology, active and passive seismology, geoelectrics, acoustic sounding, fibre-optic sensing, GNSS reflectometry, signal attenuation, and time delay techniques, cosmic ray neutron sensing, ROV and drone applications, and electromagnetic methods. Contributions can include field applications, new approaches in geophysical or in-situ survey techniques, or theoretical advances in data analysis processing or inversion. Case studies from all parts of the cryosphere, including snow and firn, alpine glaciers, ice sheets, glacial and periglacial environments, alpine and arctic permafrost as well as rock glaciers, or sea ice, are highly welcome.
This session will give you an opportunity to step out of your research focus of a single cryosphere type and to share experiences in the application, processing, analysis, and interpretation of different geophysical and in-situ techniques in these highly complex environments. This session has been running for over a decade and always produces lively and informative discussion. We have a successful history of PICO and other short-style presentations - submit here if you want a guaranteed short oral!

Co-organized by EMRP3/GI5/GM9
Convener: Jonas K. LimbrockECSECS | Co-conveners: Franziska Koch, Polona Itkin, Saskia Eppinger, Falk M. Oraschewski
CR6.3 EDI

Recent advances in sensing technology have resulted in the development of a range of ground-based methods which can “sense” cryospheric environments at high spatial (millimetre to centimetre scale) and temporal (minutes to hours) resolutions. Such close-range sensors can be used to observe rapidly evolving processes (e.g. iceberg calving, glacial lake outburst floods, supraglacial lake drainage events, snow accumulation/melting) as well as cryospheric environment at small spatial scales (e.g. small glaciers, glacierets, snow patches, rock glaciers). Such processes and environments cannot be observed using satellite Earth Observation techniques due to their coarse spatial resolution and long revisit times. In particular, close-range sensors are flexible in their deployment in the field and can observe cryospheric phenomenon from a range of viewing angles which is particularly beneficial in environments with complex topography which are commonplace across the cryosphere. Close-range sensors are therefore critical for improving process understanding but also for monitoring cryospheric hazards and the development of hazard warning systems.

In this session, we welcome contributions related to a variety of close-range sensing methods, including, but not limited to, uncrewed aerial vehicles (UAVs), radar, time-lapse photography, TLS and LiDAR. Contributions may include field-based applications, laboratory experiments, development of new systems (e.g. payloads, sensors), novel sensing networks, and new approaches related to the processing and analysis of these data. We strongly welcome case studies from all parts of the cryosphere, including glaciers (both land-based or calving), ice sheets, snow and firn, glacial and periglacial environments, and sea ice. The focus of this session will be to share experiences of developing and applying close-range sensors for cryospheric research in order to showcase the latest developments in the evolving field of research.

Co-organized by GI4
Convener: William D. HarcourtECSECS | Co-conveners: Nathaniel Baurley, Annelies Voordendag, Lauren Rawlins
CR6.4 EDI

Over the past decade, the availability of new low-frequency microwave spaceborne data has provided key parameters of the cryosphere and polar ocean that can be assimilated into Earth System Models, enhancing our understanding of fundamental processes. Among these parameters, the most significant are sea ice thickness in the lower range, sea surface salinity, soil state, and more recently, ice sheet temperature, subsurface snow melt, and the presence of aquifers. Building on these findings, new initiatives have emerged to explore the potential of using even lower frequencies (with the current lower limit being 1.4 GHz). These lower frequencies can penetrate deeper into ice and have shown greater sensitivity to sea surface salinity in cold waters. Airborne surveys conducted in Greenland and Antarctica have demonstrated the potential of low-frequency wideband radiometers in monitoring polar regions, offering unprecedented capabilities compared to existing and planned spaceborne satellites. Today, mission proposals are being developed in both the U.S. and Europe. Notably, ESA recently approved the CryoRad mission for Phase-0 studies as a potential candidate for Earth Explorer 12. CryoRad aims to address critical observational gaps through an innovative ultra-wideband 0.4–2 GHz radiometer, designed to provide groundbreaking products. The three main mission objectives are: (i) Better assess the mass balance and stability of ice sheets and ice shelves, by bridging the observation gap for ice sheet/shelf temperature profiles; (ii) Better assess the freshwater cycle and water mass formation at high latitudes, by bridging the observation gap for sea surface salinity in cold waters; (iii) Investigate sea ice dynamics and salinity exchange processes in the Arctic and Antarctic, by bridging the observation gap for sea ice salinity and 0.5-1 m sea ice thickness. The aim of the proposed session is to present the mission concept to the scientific community, discuss the methodologies for extracting geophysical parameters, and evaluate the potential impact of these new parameters on Earth System Models. Achieving this will require strong collaboration with the modeling community across various domains: oceanography and ecosystems for sea surface salinity and sea ice, glaciology and Earth system science for ice sheets and ice shelf parameters. Additionally, the climate and atmospheric communities can also contribute, given the interconnectedness of the different systems.

Convener: Giovanni Macelloni | Co-conveners: Jacqueline Boutin, Judith Freienstein
CR6.5 EDI

Remote sensing in the ‘Big Data’ era is characterised by the availability of petabytes of satellite data, facilitating observations of the cryosphere at increasingly high temporal and spatial scales. These datasets are invaluable for understanding past and contemporary changes to the cryosphere, which is particularly crucial as climate change continues and extreme events become increasingly frequent.

In order to fully utilise the wealth of satellite data available, the last decade has seen reliance on new approaches for (i) accessing, (ii) processing, (iii) interpreting, and (iv) distributing results from large-scale datasets. This includes new technologies for data access including cloud-optimised datasets; cloud geoprocessing platforms such as Google Earth Engine, Microsoft Planetary Computer, and community JupyterHubs; the increasing use of large-scale data pipelines and machine/deep learning methods to understand and monitor entire ice sheets, ice shelves, or glaciated regions; and a widespread philosophy of open data and code sharing to enable rapid dissemination of new approaches.

This session seeks contributions from anyone working on remote sensing of ice sheets, ice shelves, and glaciers. In particular, we welcome submissions from those researching the cryosphere using cloud data and processing, large-scale data pipelines, machine and deep learning, open code/data, and other contemporary approaches.

Convener: Devon Dunmire | Co-conveners: Rebecca DellECSECS, James Lea, Tom Chudley, Veronica Tollenaar
CR6.6

Radar is a prominent tool for studying ice on Earth and is becoming widespread on other planetary bodies. In this session, we hope to bring together all those interested in radar data and analysis to showcase their work, take inspiration from each other and develop new (interdisciplinary) collaborations. We aim for this session to encompass various targets, instruments and applications, such as:

- Targets: snow, firn, land ice, sea ice, lake ice, river ice and permafrost on Earth as well as the surfaces and interiors of Mars, Europa, Ganymede, The Moon, Titan, Venus, Small bodies, etc.

- Instruments: airborne and spaceborne sounders, altimeters, SAR and passive microwave radiometers as well as drones, GPR, ApRES, pRES and other radars.
Acquisition and processing: hardware, passive measurements, datasets, algorithm development, etc.

- Analysis and interpretation techniques: reflectometry, interferometry, thermometry, specularity, EM simulations, inversion, etc.

- Applications: investigations in surface-, englacial, subglacial and proglacial areas, scattering interfaces, roughness, hydrology, geothermal heat flux, material properties, fabric, modelling/supporting lab work, Earth and extraterrestrial analogs/synergies, etc.

We especially encourage the participation of Early Career Researchers and those from underrepresented groups.

Co-organized by PS7
Convener: Anja RutishauserECSECS | Co-conveners: Rebecca Schlegel, Renée Mie Fredensborg Hansen, Kirk M. Scanlan, Kristian Chan
CR6.7 | PICO

This interdisciplinary session brings together modellers and observationalists to present results and exchange knowledge and experience in the use of data assimilation in the cryospheric sciences such as inverse methods, geostatistics and machine learning. In numerous research fields it is now possible to not only deduce static features of a physical system but also to retrieve information on transient processes between different states or even regime shifts. In the cryospheric sciences a large potential for future developments lies at the intersection of observations and models with the aim to improve prognostic capabilities in space and time. Compared to other geoscientific disciplines like meteorology or oceanography, where techniques such as data assimilation have been well established for decades, in the cryospheric sciences only the foundation has been laid for the use of these techniques, one reason often being the sparsity of observations. We invite contributions from a wide range of methodological backgrounds - from satellite observations to deep-looking geophysical methods and advancements in numerical techniques - and research topics including permafrost, sea ice and snow to glaciers and ice sheets, covering static system characterisation as well as transient processes.

Co-organized by GM9
Convener: Elisa Mantelli | Co-conveners: Olaf Eisen, Irena Vankova, Johannes Sutter
CR6.8

Machine Learning (ML) is on the rise as a tool for cryospheric sciences. It has been used to label, cluster, and segment cryospheric components, as well as emulate, project, and downscale cryospheric processes. To date, the cryospheric community mainly adapts and develops ML approaches for highly specific domain tasks. However, different cryospheric tasks can face similar challenges, and when an ML method addresses one problem, it might be transferable to others. Thus, we invite the community to share their current work and identify potential shared challenges and tasks. We invite contributions across the cryospheric domain, including snow, permafrost, glaciers, ice sheets, and sea ice. We especially call for submissions that use novel machine learning techniques; however, we welcome all ML approaches, ranging from random forests to deep learning. Other contributions, such as datasets, theoretical research, and community-building efforts, are also welcome. By identifying shared challenges and transferring knowledge, we aim to channel resources and increase the impact of ML as a tool to observe, assess, and model the cryosphere.

Convener: Julia KaltenbornECSECS | Co-conveners: Kim Bente, Andrew McDonald
CL1.2.7 EDI

The half-century since the first deep ice core drilling at Camp Century, Greenland, has seen increased spatial coverage of polar ice cores, as well as extensive development in methods of ice sample extraction, analysis and interpretation. Growth and innovation continue as we address pressing scientific questions surrounding past climate dynamics, environmental variability and glaciological phenomena. New challenges include the retrieval of old, highly thinned ice, interpretation of altered chemical signals, and the integration of chemical proxies into earth system models. We invite contributions reporting the state-of-the-art in ice coring science, 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, proxy system modelling and related earth system modelling. We encourage submissions from early career researchers from across the broad international ice core science community. Contributions from on-going projects focusing on old and/or deep ice including, Green2Ice, COLDEX and Beyond EPICA Oldest Ice are very welcome.

Co-organized by CR6
Convener: Rachael Rhodes | Co-conveners: Lison Soussaintjean, Thomas Blunier, Nicolas Stoll, Daniel Baggenstos
GM2.1 EDI

Our planet is shaped by a multitude of physical, chemical and biological processes. Most of these processes and their effect on the ground’s properties can be sensed by seismic instruments – as discrete events or continuous signatures. Seismic methods have been developed, adopted, and advanced to study those dynamics at or near the surface of the earth, with unprecedented detail, completeness, and resolution. The community of geophysicists interested in Earth surface dynamics and geomorphologists, glaciologists, hydrologists, volcanologists, geochemists, biologists or engineering geologists interested in using arising geophysical tools and techniques is progressively growing and collaboratively advancing the emerging scientific discipline Environmental Seismology.

If you are interested in contributing to or getting to know the latest methodological and theoretical developments, field and lab scale experimental outcomes, and the broad range of applications in geomorphology, glaciology, hydrology, meteorology, engineering geology, volcanology and natural hazards, then this session would be your choice. We anticipate a lively discussion about standing questions in Earth surface dynamics research and how seismic methods could help solving them. We will debate about community based research opportunities and are looking forward to bringing together transdisciplinary knowledge and mutual curiosity.

Topical keywords: erosion, transient, landslide, rockfall, debris flow, fracturing, stress, granular flow, rock mechanics, snow avalanche, calving, icequake, basal motion, subglacial, karst, bedload, flood, GLOF, early warning, coast, tsunami, eruption, tremor, turbidity current, groundwater, soil moisture, noise, dv/v, HVSR, fundamental frequency, polarization, array, DAS, infrasound, machine learning, classification, experiment, signal processing.

Co-organized by CR6/SM5
Convener: Josefine UmlauftECSECS | Co-conveners: Małgorzata Chmiel, Janneke van Ginkel, Fabian Lindner, Michael Dietze
ESSI3.3 EDI

Performing research in Earth System Science is increasingly challenged by the escalating volumes and complexity of data, requiring sophisticated workflow methodologies for efficient processing and data reuse. The complexity of computational systems, such as distributed and high-performance heterogeneous computing environments, further increases the need for advanced orchestration capabilities to perform and reproduce simulations effectively. On the same line, the emergence and integration of data-driven models, next to the traditional compute-driven ones, introduces additional challenges in terms of workflow management. This session delves into the latest advances in workflow concepts and techniques essential to address these challenges taking into account the different aspects linked with High-Performance Computing (HPC), Data Processing and Analytics, and Artificial Intelligence (AI).

In the session, we will explore the importance of the FAIR (Findability, Accessibility, Interoperability, and Reusability) principles and provenance in ensuring data accessibility, transparency, and trustworthiness. We will also address the balance between reproducibility and security, addressing potential workflow vulnerabilities while preserving research integrity.

Attention will be given to workflows in federated infrastructures and their role in scalable data analysis. We will discuss cutting-edge techniques for modeling and data analysis, highlighting how these workflows can manage otherwise unmanageable data volumes and complexities, as well as best practices and progress from various initiatives and challenging use cases (e.g., Digital Twins of the Earth and the Ocean).

We will gain insights into FAIR Digital Objects, (meta)data standards, linked-data approaches, virtual research environments, and Open Science principles. The aim is to improve data management practices in a data-intensive world.
On these topics, we invite contributions from researchers illustrating their approach to scalable workflows as well as data and computational experts presenting current approaches offered and developed by IT infrastructure providers enabling cutting edge research in Earth System Science.

Co-organized by CR6/GI2/HS13/NP4/TS9
Convener: Karsten Peters-von Gehlen | Co-conveners: Miguel Castrillo, Ivonne Anders, Donatello Elia, Manuel Giménez de Castro Marciani
GM2.5

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

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

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

Co-organized by BG9/CR6/GI6/SSS11
Convener: Benoît Smets | Co-conveners: Katharina Anders, Amaury Dehecq, Anette Eltner, Livia Piermattei

CR7 – The Cryosphere in the Earth system: interdisciplinary topics

Sub-Programme Group Scientific Officers: Kirsty Langley, Cristina Pérez-Guillén

CR7.1 EDI

From glaciers and permafrost to sea ice and snowpacks, cryosphere decline has multi-faceted impacts for the environment, ecosystems, and society. These impacts span different spatial scales, from the consequences of shifting meltwater production for water resources, to the challenges of sea level rise for low-lying regions. Changing cryospheric land and seascapes, and their associated hazards, also feed into socio-cultural pressures and risk that change the ways in which people interact with and benefit from these environments. Understanding the impacts of cryospheric change across the world’s polar and mountain regions thus requires interdisciplinary and transdisciplinary research in order to communicate effectively with communities, researchers, the public, industry, and policymakers.

This session provides a platform to discuss the varied consequences of global cryospheric decline and the potential solutions to address them, with a broad and inclusive focus. We invite contributions from a range of topics focusing on the impacts of cryospheric change, including but not limited to: hazards; ecological impacts; resource security; contamination; and changes to environmental systems. Additionally, we welcome case studies that highlight mitigation and adaptation strategies to address cryospheric decline, and examples of communication beyond the scientific sphere. To effectively address the impacts of the loss of cryosphere, natural and social scientists must work together, and in collaboration with stakeholders who live in these regions, so we particularly welcome research that spans disciplinary boundaries and diverse ways of exploring and understanding these changing environments.

Convener: Caroline Clason | Co-conveners: Sally Rangecroft, Giovanni Baccolo, Louise Mercer, Chris R. Stokes
CR7.2

Understanding the likely mass balance of the Antarctic Ice Sheet in coming decades is critical to sea-level rise forecasting and the needed societal adaptions. As the ice sheet loses mass at accelerating rates, sections grounded deep beneath sea level are poised to enter a regime of irreversible rapid retreat. Most important of these is the Amundsen Sea Embayment where ocean forcing has triggered widespread changes. To project the ice sheet losses in the future we need to integrate knowledge of past ice sheet changes (marine geoscience methods) with observations (multiple geophysical observations). In turn, this better understanding leads to better modeling and projections of future changes. We welcome observational studies from both onshore and offshore realms, in present and recent past timeframes, that explore and constrain the processes affecting change.

Co-organized by OS1
Convener: Robert Larter | Co-convener: Ted Scambos
CR7.3

Recent studies highlight the hitherto underestimated sensitivity of the East Antarctic Ice Sheet (EAIS) to climate change and associated implications for global sea level rise. A significant lack of geological data (both proximal and distal to the EAIS), however, hinders the assessment of the EAIS’s response to and interaction with oceanic and atmospheric changes over various geological timescales. To identify thresholds and triggering mechanisms affecting EAIS stability, detailed paleo reconstructions of ice sheet extent, thickness, history of retreats/advances and oceanic environmental conditions (such as sea ice coverage, water temperature and ocean circulation) can provide insights into rates of change and potential ice-ocean-atmosphere interactions.
In this session we invite contributions from researchers working on the reconstruction of the EAIS glacial, deglacial and Holocene history and EAIS interaction with Southern Ocean circulation. These reconstructions may be based on, but not limited to, geological, geomorphological, geophysical and geodetic approaches, such as shelf surveys, land-based studies, and pelagic Southern Ocean sampling, which provide the basis for detailed regional reconstructions from Dronning Maud Land to Wilkes Land. The aim of this session is to stimulate interdisciplinary discussions in order to integrate terrestrial, near-shore and open marine paleo-data to enhance our understanding of ice-land-ocean-climate interactions on different spatial and temporal scales.

Convener: Sonja Berg | Co-conveners: Damian Gore, Duanne White, Sebastian Krastel, Juliane Müller
CR7.4

Along with the accelerated warming of both polar regions over recent decades, the melting of the ice sheets and sea ice in the Northern and Southern Hemispheres has attracted ample scientific attention, given their global impacts. Yet, the understanding of (i) how ice sheets, continental snow cover, permafrost and boreal forests (taken together hereafter as ‘land surface’) – key players in the hydrological and carbon cycles – respond to climate change and (ii) the interactions between the high latitude land surface and the rest of the ice-ocean-atmosphere coupled system remains limited. A better prediction of future decadal-scale variations requires a more thorough understanding of drivers and mechanisms of past decadal-scale climate variability, which can bridge discrepancies between climate models and observations using a combination of in-situ, satellite, climate proxy and modeling approaches including data assimilation. In this session we invite submissions studying the impact of drivers of polar climate and land surface on various timescales including both numerical modeling studies and observation-focused works of past climate change (historical and paleoclimate). We also welcome works studying the role of tropical-polar two-way interactions in polar climate change across seasons, focusing on the relationship of the high latitude land surface to the other components of the Earth system and lower latitudes (such as the interactions between the tropics, Southern Ocean and Antarctica or the Greenland ice sheet).

Convener: Daniel TopalECSECS | Co-conveners: Ian Baxter, Quentin Dalaiden, Edward Hanna, Hugues Goosse
CR7.5 EDI

Understanding the scale-dependent interactions of the atmosphere and the mountain cryosphere are critical for estimating the response of snow and ice to ongoing climate change. A lack of observational data and/or process understanding in high mountain regions creates substantial uncertainties with respect to future cryospheric change and how it may react to climatic variability, climatic extremes and long-term warming. Atmospheric dynamics in mountain regions are complex and further complicated by a rapidly changing cryosphere which may not be appropriately represented in atmospheric models used to estimate the mountain surface energy balance and mass changes of snow and ice.

This session aims to address the current challenges, methodological approaches and wider relevance of observing and modelling cryosphere-atmosphere interactions at varying scales in mountain environments around the world. We welcome contributions including, but not limited to, the characterisation and quantification of glacier/snow boundary layer exchanges, observations and modelling of katabatic winds and turbulent structures over the mountain cryosphere, the role of glaciers in valley circulation systems, the cryosphere and elevation-dependent warming, advances in atmospheric modelling and/or meteorological downscaling over high elevation snow and ice or the representation of glacier meteorology in numerical weather models or models of glacier energy/mass. We particularly welcome submissions related to the modulating role of cryospheric boundary layers in the face of ongoing climate changes in mountain regions.

Co-organized by AS4
Convener: Thomas Shaw | Co-conveners: Ivana Stiperski, Christina Draeger, Arindan Mandal, Lindsey Nicholson
ITS2.12/CR7.6 EDI | PICO

Atmosphere and Cryosphere are closely linked and need to be investigated as an interdisciplinary subject. Most of the cryospheric areas have undergone severe changes in last decades while such areas have been more fragile and less adaptable to global climate changes. This AS-CR session invites observational-, model- and remote sensing-based investigations on any aspects of linkages between atmospheric processes and snow and ice on local, regional and global scales. Emphasis is given on the Arctic, high latitudes and altitudes, mountains, sea ice, Antarctic-, and Alpine regions. In particular, we encourage studies that address aerosols (such as Black Carbon, Organic Carbon, dust, volcanic ash, diatoms, bioaerosols, bacteria, microplastics, etc.) and changes in the cryosphere, e.g., effects on snow/ice melt and albedo. The session also focus on dust transport, aeolian deposition, and volcanic dust, including health, environmental or climate impacts at high latitudes, high altitudes and cold Polar Regions. We include contributions on biological and ecological sciences including dust-organisms interactions, cryoconites, bio-albedo, eco-physiological, biogeochemical and genomic studies. Related topics are light absorbing impurities, cold deserts, dust storms, long-range transport, glaciers darkening, polar ecology, and more. The scientific understanding of the AS-CR interaction needs to be addressed better and linked to the global climate predictions scenarios.

Convener: Pavla Dagsson WaldhauserovaECSECS | Co-conveners: Outi Meinander, Marie Dumont, Biagio Di Mauro
CR7.7 EDI

This session welcomes research that explores the potential effectiveness, or lack thereof, of active intervention techniques for slowing or preventing sea level rise from retreating ice sheets and glaciers. Possible intervention techniques include, but are not limited to: methods for limiting ice melt or reducing calving at the ocean boundary; methods for limiting sliding at the basal boundary; and methods for increasing mass deposition or reducing ablation on the sub-aerial boundary. Research that explores the potential impact of planetary-scale climate interventions (such as Carbon Dioxide Removal or Solar Radiation Management) on ice sheets and glaciers is welcome too. We welcome numerical, theoretical, observational, or experimental physical science and engineering research aimed at evaluating the effectiveness of such interventions, as well as research focused on the legal, cultural, or economic costs and benefits thereof. Submissions from both supporters and opponents of interventions are encouraged.

Convener: Michael Wolovick | Co-conveners: Ralf Greve, Liyun Zhao
AS1.38 EDI

Mountains cover approximately one-quarter of the total land surface on the planet, and a significant fraction of the world’s population lives within, in their vicinity, and downstream. 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. This session is devoted to showcasing research that contributes to improving our 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. This includes the interaction of mountain weather and climate with the terrestrial cryosphere.

We welcome contributions describing the influence of mountains on the atmosphere on meteorological and climate time scales, including terrain-induced airflow, orographic gravity waves, 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.
We also encourage theoretical, modeling and observational studies on orographic gravity waves and their effects on the weather and the climate.

Furthermore, we invite studies that investigate climate processes and climate change in mountain areas based on monitoring and modeling activities. Particularly welcomed are contributions that connect with and address the interdisciplinary objectives of the Elevation-Dependent Climate Change (EDCC) working group of the Mountain Research Initiative ( https://mountainresearchinitiative.org/our-activities/community-led-activities/active-working-groups/elevation-dependent-climate-change/).

Co-organized by CL3.1/CR7
Convener: Sven Kotlarski | Co-conveners: Anna Napoli, Stefano Serafin, Maria Vittoria Guarino, Carolina Adler
AS4.1 EDI

The polar climate system is strongly affected by interactions between the atmosphere and the cryosphere. Processes that exchange heat, moisture and momentum between land ice, sea ice and the atmosphere, such as katabatic winds, blowing snow, ice melt, polynya formation and sea ice transport, play an important role in local-to-global processes. Atmosphere-ice interactions are also triggered by synoptic weather phenomena such as cold air outbreaks, polar lows, atmospheric rivers, Foehn winds and heatwaves. However, our understanding of these processes is still incomplete. Despite being a crucial milestone for reaching accurate projections of future climate change in Polar Regions, deciphering the interplay between the atmosphere, land ice and sea ice on different spatial and temporal scales, remains a major challenge.
This session aims at showcasing recent research progress and augmenting existing knowledge in polar meteorology and climate and the atmosphere-land ice-sea ice coupling in both the Northern and Southern Hemispheres. It will provide a setting to foster discussion and help identify gaps, tools, and studies that can be designed to address these open questions. It is also the opportunity to convey newly acquired knowledge to the community.
We invite contributions on all observational and numerical modelling aspects of Arctic and Antarctic meteorology and climatology, that address atmospheric interactions with the cryosphere. This may include but is not limited to studies on past, present and future of:
- Atmospheric processes that influence sea-ice (snow on sea ice, sea ice melt, polynya formation and sea ice production and transport) and associated feedbacks,
- The variability of the polar large-scale atmospheric circulation (such as polar jets, the circumpolar trough and storm tracks) and impact on the cryosphere (sea ice and land ice),
- Atmosphere-ice interactions triggered by synoptic and meso-scale weather phenomena such as cold air outbreaks, katabatic winds, extratropical cyclones, polar cyclones, atmospheric rivers, Foehn winds and heatwaves,
- Role of clouds in polar climate and impact on the land ice and sea ice through interactions with radiation,
Presentations including new observational (ground and satellite-based) and modelling methodologies specific to polar regions are encouraged. Contributions related to results from recent field campaigns in the Arctic and in the Southern Ocean/Antarctica are also welcomed.

Co-organized by CL2/CR7
Convener: Diana Francis | Co-conveners: Michiel van den Broeke, Michelle Maclennan
AS4.2 EDI

This session is intended to provide an interdisciplinary forum to bring together researchers working in the areas of high-latitude meteorology, atmospheric chemistry, air quality, biogeochemistry, boundary layer physics, cloud microphysics, surface radiative processes, oceanography, sea ice and climate.

The emphasis is on the role of boundary layer processes that mediate exchange of heat, momentum and mass between the Earth's surface (snow, sea-ice, ocean and land) and the atmosphere as well as the local to large-scale influences on these exchanges. An adequate understanding and quantification of these processes is necessary to improve modeling and prediction of future changes in the polar regions and their teleconnections with mid-latitude weather and climate.

It is expected that the recent implementation of long-term and new measurements from pan-Arctic networks and recent field campaigns (e.g. MOSAiC, ALPACA, ARTofMELT, POLAR CHANGEand modeling efforts, e.g. within CRiceS and PolarRES, will help diagnose large-scale and local processes as well as the coupling between local and large-scale dynamics and their impacts on climate, health and ecosystems.

We encourage submissions such as (but not limited to):
(1) External controls on the boundary layer such as clouds, radiation and long-range transport processes
(2) Results from field programs, and routine observatories, insights from laboratory studies, and advances in modeling and reanalysis,
(3) Use of data from pan-Arctic and Antarctic observing networks,
(4) Surface processes involving snow, sea-ice, ocean, land/atmosphere chemical and isotope exchanges, and natural aerosol sources
(5) Studies on atmospheric chemistry (aerosols and trace gases) and air pollution during polar winter
(6) The role of boundary layers in polar climate change and implications of climate change for surface exchange processes, especially in the context of reduced sea ice, wetter snow packs, increased glacial discharge and physical and chemical changes associated with an increasing fraction of first year ice and increasing open water.
(7) Surface energy budget of the coupled system, including contributions of ABL-dependent turbulent fluxes, clouds and radiative fluxes, precipitation and factors controlling snow/ice albedo.
(8) Sea ice dynamics and thermodynamics, e.g. wind driven sea-ice drift, snow on ice;
(9) Upper ocean mixing processes.
(10) Sea ice biogeochemistry and interactions at interfaces with sea ice.

Co-organized by CR7
Convener: Julia Schmale | Co-conveners: Priscilla Mooney, Freya Squires, Risto Makkonen, Markus Frey
AS4.4 EDI

Clouds play an important role in the Polar climate due to their interaction with radiation and their role in the hydrological cycle linking poleward water vapour transport with precipitation. Cloud and precipitation properties depend on the atmospheric dynamics and moisture sources and transport, as well as on aerosol particles, which can act as cloud condensation and ice nuclei. These processes are complex and are not well represented in the models. While measurements of cloud and precipitation microphysical properties in the Arctic and Southern Ocean/Antarctic regions are challenging, they are highly needed to evaluate and improve cloud processes representation in the models used for polar and global climate and cryosphere projections.

This session aims at bringing together researchers using observational and/or modeling approaches (at various scales) to improve our understanding of polar tropospheric clouds, precipitation, and related mechanisms and impacts. Contributions are invited on various relevant processes including (but not limited to):
- Drivers of cloud/precipitation microphysics at high latitudes,
- Sources of cloud nuclei both at local and long range,
- Linkages of polar clouds/precipitation to the moisture sources and transport, including extreme transport events (e.g., atmospheric rivers, moisture intrusions),
- Relationship of moisture/cloud/precipitation processes to the atmospheric dynamics, ranging from synoptic and meso-scale processes to teleconnections and climate indices,
- Interactions between clouds and radiation, including impacts on the surface energy balance,
- Impacts that the clouds/precipitation in the Polar Regions have on the polar and global climate system, surface mass and energy balance, sea ice and ecosystems.

Papers including new methodologies specific to polar regions are encouraged, such as (i) improving polar cloud/precipitation parameterizations in atmospheric models, moisture transport events detection and attribution methods specifically in the high latitudes, and (ii) advancing observations of polar clouds and precipitation.

Co-organized by CR7
Convener: Irina V. Gorodetskaya | Co-conveners: Florian Sauerland, Maximilian Maahn, Kerstin Ebell, Floortje van den Heuvel
G3.3 EDI

Glacial Isostatic Adjustment (GIA) refers to the Earth's response to changes in ice sheets, leading to surface deformation, changes in gravity, rotation, and the state of stress. This process is primarily driven by ice-sheet dynamics and Earth's structure, impacting other Earth systems like the cryosphere and hydrosphere. A wealth of standardized observational data, such as GNSS measurements, relative sea levels, and satellite gravimetry, helps refine GIA models. These models enhance our understanding of ice-sheet history, sea-level changes, and Earth's rheology.

We welcome contributions on GIA's effects across various scales, including geodetic measurements, complex GIA modelling, GIA-induced sea-level changes, and the Earth's response to current ice-mass changes. We also invite abstracts on GIA's impact on nuclear waste sites, groundwater, and carbon resources. This session is co-sponsored by the SCAR sub-committee INSTANT-EIS, Earth - Ice - Sea level, in view of instabilities and thresholds in Antarctica (https://www.scar.org/science/instant/home/) and the IAG/IACS sub-commission 3.4 “Cryospheric Deformation”.

Co-organized by CR7/GD1/GM9, co-sponsored by SCAR and IACS
Convener: Matthias O. Willen | Co-conveners: Holger Steffen, Jun'ichi Okuno, Valentina R. Barletta, Caroline van Calcar
PS2.5

The icy moons of our Solar System are prime targets for the search for extraterrestrial life. Moons such as Saturn's Enceladus and Jupiter's Europa are considered potential habitats because of their subglacial water oceans, which are in direct contact with the rocks below. Titan, with its potential subsurface ocean, icy surface and methane-based weather, could provide an analogue for a primordial earth and the circumstances in which life developed. To assess the habitability and sample the oceans of these moons, several approaches are being discussed, including water plume surveys on Europa and Enceladus, as well as developing key technologies to penetrate the ice and even study the ocean itself with autonomous underwater vehicles, if the ice is thin enough. Moreover, a key aspect of habitability is linked with the geological processes acting on these moons. The main questions that this session aims to address are the following:
- What can we learn from analogue studies on Earth?
- What are the properties of the ice shell and how do they evolve?
- How will planned missions to these bodies contribute to furthering our understanding?
- What measurements should be conducted by future missions?

The goal of this multidisciplinary session is to bring together scientists from different fields, including planetary sciences and the cryosphere community, to discuss the current status and next steps in the remote and in-situ exploration of the icy moons of our solar system. We welcome contributions from analogue studies, on the results of current and past missions, planned missions, mission concepts, lessons learned from other missions, and more. Contributions bridging the cryosphere-icy moons communities are of particular interest to this session.

Co-organized by CR7/GM6
Convener: Ana-Catalina Plesa | Co-conveners: Marc S. BoxbergECSECS, Tina Rückriemen-Bez

CR8 – Short courses, Outreach, Communication

Sub-Programme Group Scientific Officers: Carleen Tijm-Reijmer, Daniel Farinotti

SC 1.1 EDI

Are you unsure about how to bring order in the extensive program of the General Assembly? Are you wondering how to tackle this week of science? Are you curious about what EGU and the General Assembly have to offer? Then this is the short course for you!

During this course, we will provide you with tips and tricks on how to handle this large conference and how to make the most out of your week at this year's General Assembly. We'll explain the EGU structure, the difference between EGU and the General Assembly, we will dive into the program groups and we will introduce some key persons that help the Union function.

This is a useful short course for first-time attendees, those who have previously only joined us online, and those who haven’t been to Vienna for a while!

Co-organized by CR8/GM12/OS5
Convener: Daniel EvansECSECS | Co-conveners: Simon Clark, Rachel Oien, Giulia Consuma
SC 3.10 EDI

Discover the basics of Geodesy and geodetic data! Geodetic data, from GNSS to gravity measurements, play a crucial role in various Earth sciences, including hydrology, glaciology, geodynamics, oceanography, and seismology. Curious about what these data can (and cannot) tell us? This short course offers a crash course in core geodetic concepts, giving you the insights you need to better understand the advantages and limitations of geodetic data. While you won’t become a full-fledged geodesist by the end, you’ll walk away with a clearer picture of how to use these datasets across various fields. Led by scientists from the Geodesy division, this course is open to all, whether you frequently work with geodetic data or are simply curious about what geodesists do. Expect lively discussions and practical insights. For all geodesists, get the chance to learn what non-geodesists need when working with geodetic data!

This 60-minute short course is part of a quintet of introductory 101 courses on Geodesy, Geodynamics, Geology, Seismology, and Tectonic Modelling. All courses are led by experts who aim to make complex Earth science concepts accessible to non-experts.

Co-organized by CR8/GD11/GM12/HS11
Convener: Rebekka Steffen | Co-conveners: Öykü Koç, Eva Boergens, Benedikt Soja, Thomas Knudsen
SC 3.14 EDI

Data assimilation (DA) is widely used in the study of the atmosphere, the ocean, the land surface, hydrological processes, etc. The powerful technique combines prior information from numerical model simulations with observations to provide a better estimate of the state of the system than either the data or the model alone. This short course will introduce participants to the basics of data assimilation, including the theory and its applications to various disciplines of geoscience. An interactive hands-on example of building a data assimilation system based on a simple numerical model will be given. This will prepare participants to build a data assimilation system for their own numerical models at a later stage after the course.
In summary, the short course introduces the following topics:

(1) DA theory, including basic concepts and selected methodologies.
(2) Examples of DA applications in various geoscience fields.
(3) Hands-on exercise in applying data assimilation to an example numerical model using open-source software.

This short course is aimed at people who are interested in data assimilation but do not necessarily have experience in data assimilation, in particular early career scientists (BSc, MSc, PhD students and postdocs) and people who are new to data assimilation.

Co-organized by CR8/ESSI1/HS11/NP9
Convener: Qi Tang | Co-conveners: Lars Nerger, Armin Corbin, Yumeng Chen, Nabir Mamnun
EOS2.2 EDI

Fieldwork is essential in geoscience, it provides direct and practical experiences, produces valuable data, validates hypotheses, contextualizes findings, encourages discovery, and helps to understand and eventually solve real-world challenges faced by everyone. Fieldwork is the foundation upon which a significant part of geoscience research and understanding is built. This session is dedicated to exploring the broad range of fieldwork-related topics for education and research that can be as diverse as the fieldwork itself. Topics evolve around novel methods for conducting, teaching and planning fieldwork in a safe and welcoming manner, best practises for managing field teams, addressing sigmatised subjects (personal hygiene, safety equipment) as well as working with local communities and utilizing and sharing existing infrastructure and expertise both inside and outside of institutions. This session provides a safe space to exchange ideas on more inclusive fieldwork practices and strategies.

Co-organized by CR8/GM11/PS0
Convener: Florina Roana Schalamon | Co-conveners: Marjolein GeversECSECS, Maria Ansine Jensen, Simon Clark, Shreya Arora
EOS4.6 EDI

Science’s “open era” is here (to stay?). Data and software repositories make it possible to share and collectively develop tools and resources. Diamond open-access publishing and pre-print servers are breaking barriers to knowledge exchange. Free virtual meetings make science more accessible to those interested in listening, or speaking.

The benefits for the community are clear—better communication and more collaboration foster scientific advancement. It is therefore surprising that the vast majority of data-, tool-, and knowledge-sharing initiatives rely on the community and the community alone, without financial support from funding bodies and more often than not lacking the recognition they deserve.

We aim to bring together individuals and teams who have, in any way, served the wider geoscience community through knowledge, data, or tool creation and/or distribution. Such efforts include—but are not limited to—online learning platforms, transdisciplinary databases, open-access software and publishing.

Ultimately, this session seeks to:
1. Be a space for sharing, advertising, discussing, and recognising the value of existing resources and initiatives
2. Discuss the challenges faced by those behind them (i.e., lack of funding and institutional support) and possible strategies to eliminate these
3. Inspire new efforts, initiatives, and projects

Co-organized by AS6/CR8/GD11/GM11
Convener: Fabio Crameri | Co-convener: Lucia Perez-Diaz
EOS1.6 EDI

All science has uncertainty. Global challenges such as the Covid-19 pandemic and climate change illustrate that an effective dialogue between science and society requires clear communication of uncertainty. Responsible science communication conveys the challenges of managing uncertainty that is inherent in data, models and predictions, facilitating the society to understand the contexts where uncertainty emerges and enabling active participation in discussions. This session invites presentations by individuals and teams on communicating scientific uncertainty to non-expert audiences, addressing topics such as:

(1) Innovative and practical tools (e.g. from social or statistical research) for communicating uncertainty
(2) Pitfalls, challenges and solutions to communicating uncertainty with non-experts
(3) Communicating uncertainty in risk and crisis situations (e.g., natural hazards, climate change, public health crises)

Examples of research fitting into the categories above include a) new, creative ways to visualize different aspects of uncertainty, b) new frameworks to communicate the level of confidence associated with research, c) testing the effectiveness of existing tools and frameworks, such as the categories of “confidence” used in expert reports (e.g., IPCC), or d) research addressing the challenges of communicating high-uncertainty high-impact events.

This session encourages you to share your work and join a community of practice to inform and advance the effective communication of uncertainty in earth and space science.

Co-organized by AS6/CL3.2/CL5/CR8/GM11/OS5/PS0/SSS1
Convener: Peter Dietrich | Co-conveners: Solmaz MohadjerECSECS, Michael Pelzer, Max Schneider, Sebastian G. Mutz
EOS1.1 EDI

Science communication includes the efforts of natural, physical and social scientists, communications professionals, and teams that communicate the process and values of science and scientific findings to non-specialist audiences outside of formal educational settings. The goals of science communication can include enhanced dialogue, understanding, awareness, enthusiasm, improving decision making, or influencing behaviors. Channels can include in-person interaction, online, social media, mass media, or other methods. This session invites presentations by individuals and teams on science communication practice, research, and reflection, addressing questions like:

What kind of communication efforts are you engaging in and how you are doing it?
How is social science informing understandings of audiences, strategies, or effects?
What are lessons learned from long-term communication efforts?

This session invites you to share your work and join a community of practice to inform and advance the effective communication of earth and space science.

Co-organized by CR8/GM11/HS13/OS5/PS0/SSS1
Convener: Solmaz MohadjerECSECS | Co-conveners: Francesco Avanzi, Roberta Bellini, Usha Harris, Inka Koch