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 It is necessary to acquire more direct observations, both applying novel measurement technologies and releasing unpublished data from previous years, as well as combining in situ observations with new remote sensing products and modelling.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.

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

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.

The evolution of glaciers, ice caps, and ice sheets can have a profound impact on the Earth system. 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 glacial geological record is also often seen through the prism of the modern day processes at work on Earth. The aim of this session is to bring together researchers focused on reconstructing past glaciations and understanding glacial processes 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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

Solicited speaker: Andrea Kneib-Walter, University of Zurich, Switzerland.

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.

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.

Water 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 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. Yet, our knowledge of snow/ice accumulation and melt and their impact on runoff is highly uncertain, because of both limited availability and inherently high spatial variability of hydrological and weather data.

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;

This session will feature a solicited presentation by Prof. Bettina Schaefli from the University of Bern, Switzerland.

The session is linked to the IAHS HELPING working group on Droughts in Mountain Regions (https://iahs.info/Initiatives/Scientific-Decades/helping-working-groups/droughts-in-mountain-regions/)

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: 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.

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.

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.

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.

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.

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.

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.

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), long term monitoring (e.g., GTN-P or national/regional networks), 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.

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.

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.

NOTE: THIS SESSION WILL BE CHANGED INTO PICO FORMAT AFTER THE ABSTRACT DEADLINE ON JANUARY 15!
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.

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.

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.

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.

We are delighted to announce that in the 22nd edition of the dust session, Dr Patricia Castellanos (NASA) will provide a solicited talk about her work on airborne observations of dust.

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.

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.