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

OS – Ocean Sciences

Programme Group Chair: Johan van der Molen

OS1 – Ocean Circulation and Climate

Sub-Programme Group Scientific Officer: Joke Lübbecke

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
OS1.2 EDI

The North Atlantic exhibits a high level of natural variability from interannual to centennial time scales, making it difficult to extract trends from observational time series. Climate models, however, predict major changes in this region, which in turn will influence sea level and climate, especially in western Europe and North America. In the last decade, several observational projects have been focused on the Atlantic circulation changes, for instance ACSIS, OSNAP, OVIDE, RACE and RAPID, and new projects have started such as CANARI and EPOC. Most of these programs include both observational and modelling components. Another important issue is the interaction between the atmosphere, the ocean and the cryosphere, and how this affects the climate.

We welcome contributions from observers and modellers on the following topics:

-- climate relevant processes in the North Atlantic region in the atmosphere, ocean, and cryosphere
-- variability in the ocean and the atmosphere in the North Atlantic sector on a broad range of time scales
-- interpretation of observed variability in the atmosphere and the ocean in the North Atlantic sector
-- response of the atmosphere to changes in the North Atlantic
-- dynamics of the Atlantic meridional overturning circulation
-- role of water mass transformation and circulation changes on anthropogenic carbon and other parameters
-- changes in adjacent seas related to changes in the North Atlantic
-- atmosphere-ocean coupling in the North Atlantic realm on time scales from years to centuries (observations, theory and coupled GCMs)
-- comparison of observed and simulated climate variability in the North Atlantic sector and Europe
-- linkage between the observational records and proxies from the recent past

Convener: Bablu Sinha | Co-conveners: Caroline Katsman, Damien Desbruyeres, Elodie Duyck, Léon Chafik
OS1.3 EDI

The tropical Atlantic exhibits significant ocean variability from daily to decadal time scales, driven by complex ocean dynamics and air-sea interactions. This session is devoted to advancing the understanding of these dynamics and their climatic impacts on both adjacent and remote regions, including their interactions with other tropical basins. In addition, we are interested in the effects of climate change and variability modes on the tropical Atlantic, with a particular focus on impacts on marine ecosystems.

Relevant ocean processes include upper and deep ocean circulation, eddies, tropical instability waves, mixing, and upwellings. For air-sea interactions, we welcome studies analyzing the seasonal cycle, marine heat waves, the development of variability modes on local to basin scale (e.g., Atlantic, Dakar and Benguela Niños, Atlantic Meridional Mode and South Atlantic Ocean Dipole) and interbasin teleconnections. Wind variations related to high-frequency events, cyclones, convective systems and those shaping air-sea coupled modes are encouraged.

Finally, we seek for studies that explore the causes and impacts of systematic model errors in simulating the local to regional Atlantic climate variability. Submissions based on direct observations, reanalysis, model simulations and machine learning techniques are welcome.

Co-organized by CL2
Convener: Marta Martín-Rey | Co-conveners: Jorge López-Parages, Marie Lou Bachélery, Arthur Prigent
OS1.4 EDI

In this session, we focus on the South Atlantic Ocean, which plays a key role in regional to global climate variability but has received considerably less scientific attention than its Northern Hemisphere counterpart.

The South Atlantic connects the North Atlantic, Indian, Pacific and Southern Ocean circulations by channeling the upper and lower limb of the thermohaline circulation and being part of the wind-driven Southern Hemisphere supergyre. Local air-sea fluxes, interior mixing, and inter-basin exchange processes such as Agulhas leakage influence its northward heat and salt transport, with potential implications for the strength and stability of the Atlantic Meridional Overturning Circulation. Moreover, the South Atlantic features intricate regional ocean circulation patterns, such as the Benguela Upwelling System and the Brazil-Malvinas confluence zone. These highly productive ecosystems sustain diverse marine life and are of fundamental importance for regional fisheries. It is crucial to understand how natural variability and climate change alter South Atlantic dynamics and ecosystems. However, in situ observations are often too sparse in time to robustly infer trends, and model simulations are still showing contrasting trends.

We invite contributions that advance our understanding of the physical and biogeochemical processes governing South Atlantic regional dynamics, inter-basin exchanges, extremes and global impacts. These may cover short (e.g., seasonal) to very large (e.g., millennial) timescales and originate from observational, modelling, and paleo proxy work as well as from interdisciplinary approaches. We aim to promote discussions on future inclusive South Atlantic observing and modelling strategies.

Convener: Siren RühsECSECS | Co-conveners: Rebecca Hummels, Renellys C. Perez, Regina Rodrigues, Franz Philip Tuchen
OS1.5 EDI

While significant advances have been made recently in our understanding of the Indian Ocean’s physical, biogeochemical, and ecological characteristics and their variability across a range of spatial and temporal scales, significant gaps in our knowledge remain in observing, modeling, and predicting the Indian Ocean’s changing environmental conditions and its role in regional and global climate.
This session invites contributions based on observations, modelling, theory, and palaeo proxy reconstructions in the Indian Ocean across a range of timescales from synoptic, interannual, decadal to centennial and beyond. Topics of interest include past, current, and projected changes in Indian Ocean physical and biogeochemical properties and their impacts on ecological processes, diversity in Indian Ocean modes of variability, interactions and exchanges between the Indian Ocean and other ocean basins via both oceanic and atmospheric pathways, as well as links between Indian Ocean variability and monsoon systems. We especially encourage submissions on weather and climate extremes of societal relevance in the Indian Ocean and surrounding regions, their prediction, as well as the evaluation of climate risks, vulnerability, resilience, and adaptation and mitigation strategies. We also welcome contributions that address research on the Indian Ocean, using advanced techniques such as machine learning.

Co-organized by CL4
Convener: Caroline Ummenhofer | Co-conveners: Alejandra Sanchez-Franks, Estel Font, Yan Du, Saurabh Rathore
OS1.6 EDI

The Southern Ocean is vital to our understanding of the climate system. It is a key region for vertical and lateral exchanges of heat, freshwater, carbon, oxygen, and nutrients, with significant past and potential future global climate implications, especially around the latitudes of the Antarctic Circumpolar Current, which is the focus region for this session. The role of the Southern Ocean as a dominant player in heat and biogeochemical exchanges as well as its response to changing atmospheric forcing and increased Antarctic melting remains uncertain. Indeed, the sparsity of observations of this system and its inherent sensitivity to small-scale physical processes, not fully represented in current Earth System Models, result in large climate projection uncertainties and considerable discrepancies between observations and models. To address these knowledge gaps, the Southern Ocean is currently subject to investigations with increasingly advanced observational platforms as well as theoretical, numerical and machine learning techniques. These efforts are providing deeper insight into the three-dimensional patterns of Southern Ocean changes on sub-annual, multi-decadal and millennial timescales, as well as their potential future modifications under a changing climate. In this session, we welcome contributions concerning the role of the Southern Ocean in past, present, and future climates. These include (but are not limited to) small-scale physics and mixing, water mass transformation, gyre-scale processes, nutrient and carbon cycling, ventilation, ocean productivity, climate-carbon feedbacks, and ocean-ice-atmosphere interactions. We also welcome contributions on how changes in Southern Ocean circulation as well as heat and carbon transport affect lower latitudes and global climate more generally.

Co-organized by CL4
Convener: Alexander HaumannECSECS | Co-conveners: Channing Prend, Cara Nissen, Anja Studer, Maurice Huguenin
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
OS1.8 EDI

Polar oceans include spatial variability across a multitude of scales. From the large scale circulation, down to eddies and sub-mesoscale processes. Temporal variability includes long-term trends, climate variability and ocean extremes, as well as seasonal and high-frequency variability. Many studies of polar oceans focus on variability at a particular scale, but there is a lack of understanding of the interactions between different scales, both spatial and temporal. Furthermore, biogeochemical processes and ecosystems, which are being impacted by the rapidly changing polar oceans, respond to these changes across a range of scales. Loss of sea-ice is leading to enhanced variability at the ocean surface. This session aims to advance the understanding of polar ocean variability at different scales, with a particular focus on interactions and impacts. We encourage submissions looking at both polar regions (northern and southern hemisphere) and covering a range of approaches from observational to modelling. Associated studies on air-sea ice processes and interdisciplinary backgrounds are also welcome.

Co-organized by CL4
Convener: Ruijian GouECSECS | Co-conveners: Yanni Wang, Paul G. Myers, Klara Wolf, Gerrit Lohmann
OS1.9 EDI

The ocean surface layer mediates the transfer of matter, energy, momentum, heat, and trace gases between the ocean, atmosphere and sea ice, and thus plays a central role in the dynamics of the climate system. This session will focus on the ocean surface layer globally, from the coasts – including the marginal sea ice zone – to the pelagic ocean, and its interactions with the overlaying low atmosphere. We will discuss in particular recent advances in the understanding of (sub-)mesoscale and internal-wave dynamics, ocean surface-interior interactions, ice-ocean interactions, particle and tracer dispersion as well as boundary-layer turbulence and surface-wave effects. We also encourage studies focusing on the coupling of physical, biological, and biogeochemical processes. Of special interest will be contributions describing the impact of ocean surface-layer processes on air-sea fluxes and atmosphere-ocean feedbacks. These include the parameterization of air-sea interactions, the impact of tropical cyclones, and the role of extreme events. Our session welcomes observational (from in-situ to remote sensing), theoretical and numerical investigations focusing on the ocean surface layer and its interactions with the atmosphere and sea ice, regardless of the temporal and spatial scales considered.

Co-organized by AS4/NP3
Convener: Lars Umlauf | Co-conveners: Jeff Carpenter, Pauline Tedesco, Pierre-Etienne Brilouet
OS1.10

We invite presentations on ocean surface waves, and wind-generated waves in particular, their dynamics, modelling and applications. This is a large topic of the physical oceanography in its own right, but it is also becoming clear that many large-scale geophysical processes are essentially coupled with the surface waves, and those include climate, weather, tropical cyclones, Marginal Ice Zone and other phenomena in the atmosphere and many issues of the upper-ocean mixing below the interface. This is a rapidly developing area of research and geophysical applications, and contributions on wave-coupled effects in the lower atmosphere and upper ocean are strongly encouraged

Co-organized by NP7
Convener: Alexander Babanin | Co-conveners: Fangli Qiao, Miguel Onorato, Francisco J. Ocampo-Torres
OS1.11 EDI

Energy conservation is a fundamental physical principle, yet it is generally not achieved in state-of-the-art models of geophysical flows owing to, for instance, the governing equations and their discretization, the coupling between model components, or the parameterization of unresolved processes. It is thus non-trivial to close the energy budget, which becomes even more challenging due to the multitude of oceanic processes that undergo nonlinear interactions and drive energy transfers across a range of scales: from eddies to internal waves to small-scale turbulence. This session is devoted to understanding these multi-scale interactions and associated energy transfers in the ocean, which are ultimately crucial for developing energetically consistent models, confidently predict climatic changes, and quantify associated uncertainties, and thus improve our understanding of the climate system.

We invite contributions on oceanic energy pathways and their consistent representation in numerical models from theoretical, modeling, and observational perspectives. These include, but are not limited to, the processes involving mesoscale eddies, internal gravity waves, instabilities, turbulence, small-scale mixing, and ocean-atmosphere coupling. Contributions on energy transfer processes and their quantification from in-situ measurements, (semi-)analytical approaches, and numerical models, as well as their parameterizations and spurious energy transfers associated with numerical discretizations, are also welcome along with interdisciplinary contributions such as novel applications in data science that diagnose, quantify, and minimize energetic inconsistencies and related uncertainties.
We particularly encourage early career researchers to participate in this session.

Convener: Nils Brüggemann | Co-conveners: Manita Chouksey, Knut Klingbeil, Stephan Juricke, Friederike Pollmann
OS1.12 EDI

Theoretical and model studies show that the non-linear ocean spontaneously generates a strong, multi-scale random intrinsic variability. Equivalently, uncertainties in initial ocean states tend to grow and strongly affect the simulated variability up to multidecadal and basin scales, with or without coupling to the atmosphere. In addition, ocean simulations require both the use of subgrid-scale parameterizations that crudely mimic unresolved processes, and the calibration of the parameters associated with these parameterizations. In this context of multiple uncertainties, oceanographers are increasingly adopting ensemble simulation strategies, probabilistic analysis methods, and developing stochastic parameterizations for modeling and understanding the ocean variability in response to (or in interaction with) the atmospheric evolution.

Presentations are solicited about the conception and analysis of ocean ensemble simulations, the characterization of ocean model uncertainties, and the development of parameterizations for ocean models. The session will also cover the dynamics and structure of intrinsic ocean variability, its relationship with atmospheric variability, and the use of adequate concepts (based on e.g. dynamical systems, information, or other theories) for the investigation of oceanic variability. We welcome as well studies about the propagation of intrinsic ocean variability towards other components of the climate system, about its implications regarding ocean predictability, operational forecasts, detection and attribution of climate signals, climate simulations and projections.

Co-organized by NP2
Convener: Thierry Penduff | Co-conveners: Lin Lin, Sally Close, Takaya Uchida
OS1.13

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

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

Co-organized by BG4/CL3.1
Convener: Ivy Frenger | Co-conveners: Andreas Klocker, Lucie Knor, Anna Katavouta
OS1.14 EDI

The oceans are changing rapidly in response to the changing climate manifested in record-breaking temperatures in the North Atlantic, altered ocean currents, and changes in the marine carbon system. Further changes are expected in a warmer future climate. Understanding the mechanisms of oceanic climate change are crucial to develop realistic ocean projections. The latest projections, simulated using the recent Climate Model Intercomparison Project (CMIP) phase 6, provide meaningful insights on the ocean circulation responses under various climate change scenarios. These projections are essential to quantify the impacts of oceanic climate change and in developing successful adaptation strategies. This session will bring together people with the common interest of what the future ocean circulation will look like.

We encourage submissions from studies covering global, basin wide, regional, or coastal changes. Topics covering changing ocean circulation and transports, variability and trends, tipping points and extremes, as well as temperature, salinity and biogeochemistry are welcomed. This session is not limited to CMIP analysis but submissions using other modelling datasets and statistical projections are very much encouraged.

Co-organized by CL3.1
Convener: Jennifer Mecking | Co-conveners: René van Westen, Marius Årthun, Yiwen Li
ITS5.6/OS1.15

Modern observations reveal that the narrow and shallow Atlantic and Pacific gateways connecting the Arctic Ocean to adjacent seas are undergoing substantial physical and biological changes due to sea ice loss and warming temperatures. Model projections suggest that these changes will intensify under future climate scenarios, while paleoclimate records demonstrate that the Arctic Ocean has experienced similar transformations in the past, emphasizing the need to contextualize modern climate change within a longer-term perspective. This session aims to convene the broad scientific community investigating the "Atlantification" and "Pacification" of the Arctic Ocean from diverse perspectives, including physical oceanography, marine ecology, paleoclimatology, and modeling. We welcome contributions encompassing in-situ physical and ecological observations, satellite remote sensing, proxy-based and model-based paleo-reconstructions, and future model projections. This session aims to foster interdisciplinary exchange among scientists with diverse backgrounds to collectively address the complex mechanisms and feedbacks driving changes at the Arctic Ocean gateways.

Convener: Tommaso Tesi | Co-conveners: Margit Simon, Marius Årthun, Cecilia Peralta-Ferriz, Igor Polyakov
CL2.6 EDI

The global ocean absorbs, stores, and redistributes vast amounts of heat, freshwater, carbon, oxygen, and nutrients and is a main driver for shaping the global climate. Anthropogenic forcing is superimposed on the ocean’s natural variability and complex interactions and feedback occur across scales and impacting multiple scientific disciplines. For detecting and subsequently understanding the signatures of climate variability in general, and the anthropogenic part in particular, probably the most established approach is using time series records.
In this session, we invite submissions on research that make use of Eulerian (fix-point) ocean time series of Essential Ocean Variables (EOV) from observational data and/or from modelling studies. Submissions are encouraged from all ocean science disciplines, across ocean compartments – from the air/sea interface, across the water column, to sea-floor processes –, and also from integration of different observing platforms (e.g., moorings, ships, satellites, Argo floats, gliders). Research on interaction of ocean processes, their forcing, and effects are most welcome and may address themes such air/sea heat and freshwater fluxes and carbon and oxygen uptake; ocean transport; biogeochemical and biological time series; as well as deep ocean and sea-floor processes.

Co-organized by OS1
Convener: Raquel Somavilla | Co-conveners: Johannes Karstensen, Jinyong Jeong, Dariia Atamanchuk, Yao Fu
CL4.7 EDI

The modeling of the Earth Climate System has undergone outstanding advances to the point of resolving atmospheric and oceanic processes on kilometer-scale, thanks to the development of high-performance computing systems. Models resolving km-scale processes (or storm-and-eddy-resolving models) on a global scale are also able to resolve the interaction between the large and small-scale processes, as evidenced by atmosphere- and ocean-only simulations. More importantly, this added value comes at the expense of avoiding the use of parameterizations that interrupts the interaction between scales, i.e., convective parameterization in the atmosphere or mesoscale eddy parameterization in the ocean. These advantages are the bases for the development of global-coupled storm-and-eddy-resolving models, and even at their first steps, such simulations can offer new insights into the importance of capturing the air-sea interface and their associated small-scale processes in the representation of the climate system.
The objective of this session is to have an overview of the added values of global simulations using storm-resolving atmosphere-only configuration, eddy-resolving ocean-only models, and to identify which added values stay after coupling both components, i.e., mechanisms not distorted by the misrepresentation of sub-grid scale processes in the atmosphere and ocean. In addition to highlighting the importance of the already resolved processes in shaping the climate system in global storm-and-eddy-resolving models, this session is also dedicated to presenting the current challenges in global storm-and-eddy-resolving models (identification of biases and possible solutions) by pointing to the role of the sub-grid scale processes in shaping processes on the large scale.
We call for studies contributing to highlighting the advantages and challenges of using global storm-and-eddy-resolving models in ocean-only, atmosphere-only, and coupled configurations, such as the ones proposed by NextGEMS, EERIE, DestinE, and WarmWorld, as well as studies coming from independent institutions around the world

Co-organized by AS5/OS1
Convener: Hans SeguraECSECS | Co-conveners: Audrey Delpech, Tobias Becker, Daisuke Takasuka, Thomas Rackow
CL4.1 EDI

The dynamics of the atmosphere in the extratropics is characterized by the coexistence of multiple fundamental processes spanning a variety of spatio-temporal scales. The interactions between the atmosphere and the oceans are central to several of these, while the interaction with sea-ice also plays a major role in high latitudes. The thermal contrast between the ocean and land surface, the different thermal inertia of the ocean and the atmosphere, and the moisture and heat exchange between the two are important for the general circulation of the atmosphere and oceans, and indicate that both a thermodynamic and a dynamic perspective are needed for understanding this topic. For example the oceanic anomalies, through air-sea interactions, affect the atmospheric dynamics already at the weather scales, and the atmosphere can quickly transfer anomalies towards remote areas, as in the case of diabatic heating along frontal zones. Atmospheric rivers originating over oceanic surfaces affect the formation of synoptic systems in the mid-latitudes and trigger climate extremes. Careful understanding of these mechanisms is crucial, especially regarding the assessment and predictability of extreme events, and the capability to discern the impacts of anthropogenic climate change on the variability of the climate system.
We welcome all contributions on the interactions between the oceanic and atmospheric circulation. These include investigations of atmosphere – ocean dynamics and thermodynamics at hemispheric and regional scales, including the role of sea-ice, and both weather and climate timescales. We also encourage submissions that address and compare different methodologies, e.g. detection of dominant patterns or weather regimes, dimensionality reduction involving traditional techniques such as PCA and EOFs, or new methods such as random forest or other AI-based algorithms. Model intercomparisons, and evaluations of past and future climate projections, are also welcome.

Co-organized by AS4/NP3/OS1
Convener: Valerio Lembo | Co-conveners: Sayantani Ojha, Rune Grand Graversen, Joakim Kjellsson
CL4.17 EDI

To address societal concerns over rising sea levels and associated extreme events and to quantify the impacts of sea-level changes on coastal communities, ecosystems and the global economy it is key to understand the contributions to these changes. In this session, we respond to this need and invite contributions from the international sea level community that improve our knowledge of the past, present and future changes in global and regional sea levels, extreme events and coastal impacts.

The session focuses on studies exploring the physical mechanisms for sea level rise and variability as well as the drivers of these changes, at any time scale (from paleo sea level to high-frequency phenomena to long-term projections), using observations and/or model simulations. Investigations on linkages between variability in sea level, heat and freshwater content, ocean dynamics, land subsidence and mass exchanges between the land and the ocean associated with ice sheet and glacier mass loss and changes in the terrestrial water storage are welcome. Studies focusing on future sea level changes are encouraged, as well as those assessing short-, medium-, and long-term impacts on coastal environments and their implications.

Co-organized by OS1
Convener: Aimée Slangen | Co-conveners: Alexander Nauels, Jennifer Weeks, Jeemijn Scheen, Ying Qu
CL4.6 EDI

This session covers climate predictions from seasonal to multi-decadal timescales and their applications. Continuing to improve such predictions is of major importance to society. The session embraces advances in our understanding of the origins of seasonal to decadal predictability and of the limitations of such predictions. This includes advances in improving forecast skill and reliability and making the most of this information by developing and evaluating new applications and climate services.
The session welcomes contributions from dynamical models, machine-learning or other statistical methods and hybrid approaches. It will investigate predictions of various climate phenomena, including extremes, from global to regional scales, and from seasonal to multi-decadal timescales (including seamless predictions). Physical processes and sources relevant to long-term predictability (e.g. ocean, cryosphere, or land) as well as predicting large-scale atmospheric circulation anomalies associated with teleconnections will be discussed. Analysis of predictions in a multi-model framework, and ensemble forecast initialization and generation will be another focus of the session. We are also interested in approaches addressing initialization shocks and drifts. The session welcomes work on innovative methods of quality assessment and verification of climate predictions. We also invite contributions on the use of seasonal-to-decadal predictions for risk assessment, adaptation and further applications.

Co-organized by AS1/ESSI4/HS13/NP5/OS1
Convener: André Düsterhus | Co-conveners: Bianca Mezzina, Leon Hermanson, Leonard Borchert, Panos J. Athanasiadis
CL4.8 EDI

One of the big challenges in Earth system science consists in providing reliable climate predictions on sub-seasonal, seasonal, decadal and longer timescales. The resulting data have the potential to be translated into climate information leading to a better assessment of global and regional climate-related risks.
The main goals of the session is (i) to identify gaps in current climate prediction methods and (ii) to report and evaluate the latest progress in climate forecasting on subseasonal-to-decadal and longer timescales. This will include presentations and discussions of developments in the predictions for the different time horizons from dynamical ensemble and statistical/empirical forecast systems, as well as the aspects required for their application: forecast quality assessment, multi-model combination, bias adjustment, downscaling, exploration of artificial-intelligence methods, etc.
Following the new WCRP strategic plan for 2019-2029, prediction enhancements are solicited from contributions embracing climate forecasting from an Earth system science perspective. This includes the study of coupled processes between atmosphere, land, ocean, and sea-ice components, as well as the impacts of coupling and feedbacks in physical, hydrological, chemical, biological, and human dimensions. Contributions are also sought on initialization methods that optimally use observations from different Earth system components, on assessing and mitigating the impacts of model errors on skill, and on ensemble methods.
We also encourage contributions on the use of climate predictions for climate impact assessment, demonstrations of end-user value for climate risk applications and climate-change adaptation and the development of early warning systems.
A special focus will be put on the use of operational climate predictions (C3S, NMME, S2S), results from the CMIP5-CMIP6 decadal prediction experiments, and climate-prediction research and application projects.
An increasingly important aspect for climate forecast's applications is the use of most appropriate downscaling methods, based on dynamical, statistical, artificial-intelligence approaches or their combination, that are needed to generate time series and fields with an appropriate spatial or temporal resolution. This is extensively considered in the session, which therefore brings together scientists from all geoscientific disciplines working on the prediction and application problems.

Co-organized by ESSI1/HS13/NP5/OS1
Convener: Andrea Alessandri | Co-conveners: Yoshimitsu Chikamoto, Tatiana Ilyina, June-Yi Lee, Xiaosong Yang
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
CR2.2 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
CR2.4 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
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
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
BG1.2 EDI

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

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

Co-organized by AS3/OS1
Convener: Jens TerhaarECSECS | Co-conveners: Yohanna Villalobos Cortes, Marta López Mozos, Ronny Lauerwald, Ana Bastos
NP1.2 EDI

Projections of future climate rely on increasingly complex, high-resolution earth system models (ESMs). At the same time, nonlinearities and emergent phenomena in the climate system are often studied by means of simple conceptual models, which offer qualitative process understanding and allow for a broad range of theoretical approaches. Simple climate models are also widely used as physics-based emulators of computationally expensive ESMs, forming the basis of many probabilistic assessments in the IPCC 6th Assessment Report.

Between these two approaches, a persistent “gap between simulation and understanding” (Held 2005, see also Balaji et al. 2022) challenges our ability to transfer insight from simple models to reality, and distill the physical mechanisms underlying the behavior of state-of-the-art ESMs. This calls for a concerted effort to learn from the entire model hierarchy, striving to understand the differences and similarities across its various levels of complexity for increased confidence in climate projections.

In this session, we invite contributions from all subfields of climate science that showcase how modeling approaches of different complexity advance our process understanding, and/or highlight inconsistencies in the model hierarchy. We also welcome studies exploring a single modeling approach, as we aim to foster exchange between researchers working on different rungs of the model hierarchy. Contributions may employ dynamical systems models, physics-based low-order models, explainable machine learning, Earth System Models of Intermediate Complexity (EMICs), simplified or idealized setups of ESMs (radiative-convective equilibrium, single-column models, aquaplanets, slab-ocean models, idealized geography, etc.), and full ESMs.

Processes and phenomena of interest include, but are not limited to:
* Earth system response to forcing scenarios (policy-relevant, extreme, counterfactual)
* Tipping points and abrupt transitions (e.g. Dansgaard-Oeschger events)
* Coupled modes of climate variability (e.g. ENSO, AMV, MJO)
* Emergent and transient phenomena (e.g. cloud organization)
* Extreme weather events

Co-organized by AS5/CL4/OS1
Convener: Oliver MehlingECSECS | Co-conveners: Reyk Börner, Raphael Roemer, Maya Ben Yami, Franziska Glassmeier
NP2.2 EDI

The Earth's climate system is characterized by the intricate interplay of atmospheric and oceanic processes evolving at various timescales, exhibiting complex behaviors and nonlinear interactions. Gaining a deeper insight into the underlying dynamics of this system is crucial for understanding the physical origins of weather and climate variability, as well as for predicting climate trends and extreme events. However, this task poses significant challenges, as traditional theoretical approaches alone often fall short in capturing the full extent of these complexities. To address these challenges, data-driven methods have increasingly become indispensable tools in the study of oceanic and atmospheric dynamics.

Over the past few decades, the application of data-driven approaches has led to substantial advancements in our understanding of climate systems. Linear techniques such as normal modes, wave analysis, and Fourier methods, have long been employed to extract relevant spatiotemporal features and identify key climate modes. Furthermore, empirical dynamical methods, such as Linear Inverse Models (LIMs), have proven invaluable for the study and prediction of climate phenomena like the El Niño-Southern Oscillation (ENSO).

In recent years, the advent of non-linear data-driven methodologies has opened new avenues in the field. Techniques such as transfer operators, including Koopman mode decomposition, and various machine learning approaches have significantly broadened the scope of what can be achieved in the analysis and forecasting of climate dynamics. These methods offer potential to uncover complex patterns, improve climate predictability, and develop more accurate reduced-order models that capture the essence of the underlying dynamical processes, holding great potential for enhancing our understanding of complex atmospheric and oceanic climate processes.

This session aims to bring together researchers at the forefront of applying data-driven methods to study oceanic and atmospheric dynamical systems. We invite contributions that explore the application of these methodologies in various aspects of climate science, including (but not limited to) the following topics:

- Climate Predictability and Forecasting

- Spatiotemporal Feature Extraction

- Climate Mode Identification

- Climate Network Analysis

- Exploration of Climate Attractors

- Development of Reduced-order Models

- Extreme Event Analysis

Co-organized by AS4/OS1
Convener: Paula Lorenzo SánchezECSECS | Co-conveners: Matthew Newman, Antonio Navarra
EOS2.3 EDI

“The truth is almost ten years since the Paris Agreement was adopted, the target of limiting long-term global warming to 1.5 degrees Celsius is hanging by a thread.
"The truth is the world is spewing emissions so fast that by 2030, a far higher temperature rise would be all but guaranteed. …
"Now is the time to mobilise, now is the time to act, now is the time to deliver. This is our moment of truth.” (Guterres, 2024)

One of the surest ways to mobilise, to act and deliver is through geo-education, geo-communication and geoethics. Humanity is dependent on both the climate and the ocean, and on their interaction. The danger of climate and ocean change can be applied, mutatis mutandis, to related threats, such as biodiversity, pollution, food security and fossil-fuel-driven war. Humanity appears to be in the grip of manic growth and ecological overshoot.

Far greater numbers of citizens than is currently the case need to increase their knowledge and communication skills in climate and ocean change and their underlying causes. This is achieved through a broad variety of methods: encounters, meetings, field trips, associations, classes, publications, peer pressure, workshops, geoethical awakening, social media, direct experience of extreme weather, association memberships, legal action and so on.

We welcome abstracts on a broad range of topics, from hands-on geo-communication of all kinds, through pedagogical ideas and practices, best practices, research, programme implementation and activism. Come and share your experience, your ideas, your anger, your vision, your research, your drive, your actions, your successes – from hands-on pedagogical ideas and practices, through geo-communication, curriculum matters and research, to policy and its implementation.

This session is organised in parallel to, but independently of, the special issue of the EGU journal *Geoscience Communication*, see https://gc.copernicus.org/articles/special_issue1271.html. You are invited to submit an article; be in touch directly with David.

Co-organized by CL3.2/GM11/OS1/OS5, co-sponsored by IAPG
Convener: David Crookall | Co-conveners: Giuseppe Di Capua, Svitlana Krakovska, Rachel Wellman, Pimnutcha Promduangsri

OS2 – Coastal Oceans, Semi-enclosed and Marginal Seas

Sub-Programme Group Scientific Officer: Sandro Carniel

OS2.1 EDI

Contributions are invited on recent advances in the understanding of circulation and fluid dynamical processes in coastal and shelf seas. Observational, modelling and theoretical studies are welcome, spanning the wide range of temporal and spatial scales from the shelf break to the shore. In order to capture the dynamic nature of our coastal and shelf seas the session includes processes such as shelf circulation, canyon flows, exchange flows in semi-enclosed seas, eddies, river plumes and estuaries, as well as on flow interactions with bio-geochemistry, sediment dynamics, morphology and nearshore physics. Contributions on impacts of climate change and man-made structures on our coastal seas and estuaries are also welcome.

Convener: Julie D. Pietrzak | Co-conveners: Andreas Lehmann, Hans Burchard, Evridiki Chrysagi
OS2.2 EDI

Coastal oceanographic processes present important differences with deep water oceanography, resulting in higher prediction errors, where topo-bathymetry in shallow areas exerts a strong control on hydrodynamic fields, further modified by stratification, land boundaries and coastal infrastructure. Predictability is limited by strong non-linear interactions (e.g. breaking waves, nearshore circulation and sediment fluxes), choice of numerical strategies (e.g. nested meshes, finite-elements or smooth-particle simulations) or modulations typical of restricted domains (e.g. seiching or vegetation filtering). Coastal observations (in-situ and remote) are therefore necessary to enhance numerical models, where the advent of new satellite capabilities (e.g. Sentinel resolution and sensors) and modelling advances (e.g. coupling or unstructured grids), together with enhanced coastal observatories, are leading to qualitative advances for coastal oceanography applications. Coastal analyses under future scenarios become even more challenging, since transitional areas are more strongly impacted by changing climates (e.g. changing domains due to sea-level rise). For these reasons, it is timely to discuss recent advances in: a) coastal coupled hydro-morpho-ecological modelling at different scales; b) coastal aggregation of in-situ/satellite/numerical data from different sources; c) knowledge-based coastal applications, including the assessment of nature-based interventions; d) use of novel approaches, such as data assimilation or machine learning; and e) uncertainties in coastal decision-making. Building on these challenges, we invite presentations on coastal modelling, data assimilation, boundary effects or operational coastal predictions with/without interactions with Nature-based or traditional interventions. Contributions tackling open questions on non-linear response functions, artificial intelligence or big data for coastal applications are welcome. These coastal topics should conform a fruitful session for discussing coastal oceanography applications, including conventional and nature-based interventions under climate change. We offer the possibility, for interested authors, to submit evolved versions of their presentations to the currently open special issue in Ocean Sciences (see https://www.ocean-science.net/articles_and_preprints/scheduled_sis.html).

Convener: Agustín Sánchez-Arcilla | Co-conveners: Joanna Staneva, Sandro Carniel, Davide Bonaldo, Manel Grifoll
OS2.3 EDI

Tides influence a wide range of ocean and Earth system processes, from the coasts to the deep ocean. Together with storm surges, they play a central role in driving coastal flooding. Tides provide the mechanical energy that fuels ocean mixing and sustains large-scale circulation, affecting marine biogeochemistry, ecosystems, and interacting with ice sheet and sea ice dynamics.
Tides and storm surges act as key drivers of coastal processes, exerting a combined influence on coastal hazards such as flooding, morphological changes, pollution, and infrastructure resilience. The behaviour and interaction of tides and storm surges, in combination with other coastal processes, represents an active research field that will be discussed in this session.
Both tides and storm surge patterns exhibit short and long-term temporal variability across different spatial scales and are modified by sea-level rise, climate change, sea ice, and human activities such as dredging and estuarine modifications. These changes have implications for coastal flooding, tidal energy generation, ocean stratification, mixing and large-scale ocean circulation. Further back in geological time, changes in continental configuration and sea level profoundly altered tidal dynamics, with potentially far-reaching effects on ocean circulation, mixing and evolutionary processes.
Observations (in-situ measurements and remote sensing), models (numerical and data-driven) and geological reconstructions are important tools in understanding how tides and storm surges vary across space and time. The aim of this session is to share innovative approaches, technical advancements in observation and modelling techniques, and recent improvements in understanding of these tide- and surge-driven processes and their implications for coastal, ocean and Earth system processes. Submissions are encouraged both from regional and global-scale studies on all aspects of tides and surges in the past, present and future, including those from estuaries, rivers, lakes, and even other planetary bodies.

Co-organized by G3
Convener: Sophie-Berenice WilmesECSECS | Co-conveners: Peter Robins, Joanne Williams, Friederike Pollmann, Roman Sulzbach
OS2.4 EDI

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

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

Co-organized by BG8/GM8
Convener: Laurent Amoudry | Co-conveners: Kaja Gentsch, Markus Meier, Maren Voss
OS2.5

Coastal oceans are dynamic interfaces between land and sea, playing a critical role in global biogeochemical cycles with a high impact on socio-economic activities and social developments. The dynamic and physical processes as well as the human activities that take place in coastal areas make them natural laboratories to improve our knowledge about several biogeochemical interactions. In addition, these regions are affected by both natural and anthropogenic factors such as coastal acidification, organic matter, nutrients, and pollution, among others. All these factors have impacts on the natural cycles and the magnitude of these impacts should be studied and understood in order to propose solutions to the decision makers that could help to know, understand, take decisions, and protect or regulate the coastal environments.
This session aims to bring together researchers from diverse fields to discuss the latest findings on the biogeochemical processes occurring in coastal oceans, improve our knowledge, identify impacts, and propose solutions. We welcome research studies that focus on both natural and anthropogenic processes that are affecting the trace metal chemistry, CO2 system, ocean acidification, nutrient cycle, organic matter, CO2 sequestration and their impacts on the chemical processes, etc.

Convener: Aridane González González | Co-conveners: David González-Santana, J. Magdalena Santana-Casiano, Melchor Gonzalez-Davila
OS2.6 EDI

The global carbon cycle involves the flux, storage, and transformations of carbon in different forms across and within a variety of major reservoirs. Particularly, the land and the ocean carbon reservoirs are key gatekeepers controlling atmospheric carbon dioxide and Earth’s climate. In recent years, there has been growing recognition of the need to understand the carbon cycle not as an isolated system within specific environments but as a dynamic and interconnected process, especially spanning the entire land-to-ocean aquatic continuum (LOAC). The LOAC—including inland waters, rivers, estuaries, tidal wetlands, and continental shelf waters—serves as a vital pathway for carbon transport and transformations. Moreover, the riverine input of carbon to the ocean remains a poorly understood yet important component of the global carbon budget. A better understanding of the carbon cycle along the LOAC is crucial to supporting the development of climate policies, projecting future climate change, and monitoring, reporting, and verifying (MRV) carbon dioxide removal interventions.
This session seeks to bring together scientists studying various forms of carbon—organic, inorganic, dissolved, and particulate — to deepen our understanding of how human activities are reshaping the carbon cycle within the LOAC. We welcome research that explores carbon dynamics in the LOAC, particularly about the changes driven by anthropogenic impacts, including but not limited to:
- Characterisation of the carbon flux from land to ocean and the impacts of human activities on that flux
- Quantifying anthropogenic-influenced carbon in inland waters and rivers, estuaries and tidal wetlands, continental shelf waters, and freshwater/coastal/marine sediments.
- Quantification of the ocean carbon sink in coastal waters
- Redistribution of carbon among different carbon forms under anthropogenic perturbations.
- Changes in biogeochemical processes due to natural variability and anthropogenic impacts that influence the LOAC carbon cycle.
- Impacts of carbon dioxide removal interventions on the LOAC carbon cycle.
We strongly encourage contributions using diverse approaches, including cruise-based observations, autonomous platform observations, and machine learning and modeling techniques.

Convener: Xinyu LiECSECS | Co-conveners: Jonathan Sharp, Junjie Wang, Goulven G. Laruelle, Neill Mackay
OS2.7

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

Co-organized by BG4
Convener: Eugenio Ruiz-Castillo | Co-conveners: Josefa VerdugoECSECS, Laura Gillard, Johnna Holding
OS2.8

This session, organized by the UN Decade Program CoastPredict, aims to directly contribute to the UN Decade Challenge 6: Enhancing community resilience to ocean hazards. The focus is on addressing critical gaps in scientific knowledge, particularly in key areas such as coastal risk assessment, warning and mitigation strategies. Key topics include: (i) the collection and generation of observational and modeling datasets essential for risk assessment, including downscaled climate projections for coastal regions, all within a robust data-sharing frameworks; (ii) the promotion of interdisciplinary and international research and innovation to comprehensively address these challenges c, with a particular emphasis on approaches like Digital Twin technology; (iii) the enhanced Early Warning Systems for Ocean-related Hazards through Machine learning and Predictive Modeling, and (iv)the development of standards for risk communication at both national and international levels. The session will also explore multi-hazard early warning systems for events such as tsunamis, storm surges, marine heatwaves, and coastal biogeochemical hazards, including pollution and other extreme coastal events such as erratic extratropical cyclones Contributions on machine learning applications, compound event analysis, and disaster risk reduction strategies are strongly encouraged, as are science-based management practices for enhancing coastal resilience. By leveraging innovative tools like digital twins, this session highlights how predictive modeling can significantly improve risk assessment and response strategies. Its relevance extends to policymakers, scientists, and coastal communities, fostering collaboration to strengthen coastal resilience.

Convener: Giovanni Coppini | Co-conveners: Nadia Pinardi, Agustín Sánchez-Arcilla, Vijaya Sunanda, Joanna Staneva
ESSI4.10 EDI

The coastal zone is globally of great environmental and economic importance, but the stability and sustainability of this region faces many threats. Climate-induced sea level rise, coastal erosion and flooding due to increased storms, and pollution and disturbance of ecosystems are all stresses shaping the present coastline and near-shore environments. These direct impacts on the coast are driving coastline management and marine policies worldwide.



These initiatives rely on key, up-to-date, and repeatable environmental information layers, which are required to effectively monitor coastal change and make informed and coordinated decisions on the sustainable use of coastal and marine resources, in alignment with climate strategies and the protection of coastal areas.



To address this need, advanced methodologies based on remote sensing are becoming more widely used. These techniques have benefited from the surge of Earth Observation data, and advancements in computational and classification algorithms. In recent years, together with the upsurge of cloud computing, there has been a growing focus on new challenges such as sensor and data fusion from multiple sources, and its potential application to effectively monitoring the changes in coastal environments.



This session calls for papers that advance our capability or understanding of the application of Earth Observation remote sensing to coastal zone monitoring, with specific interest in contributions that (1) develop novel methodologies or data fusion workflows in coastal geomorphology, near-shore satellite-derived bathymetry, coastal altimetry, coastal dynamics, water quality and coastal ecosystems (2) include validation and uncertainty budgets, (3) incorporate temporal resolution for monitoring and prediction of coastal change, and (4) impact a wide range of applications.

Co-organized by OS2
Convener: Xavier Monteys | Co-conveners: Paula Gomes da Silva, Salvatore Savastano

OS3 – Ocean Biogeochemistry and Biology

Sub-Programme Group Scientific Officer: Peter Landschützer

OS3.1 EDI

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

Co-organized by AS2/BG4
Convener: Oliver Wurl | Co-conveners: Janina Rahlff, Dr. Naama Lang-Yona, Ana Cvitesic Kusan, Lasse Jensen
OS3.2

Gelatinous zooplankton (GZ), including jellyfish, salps, and ctenophores, are increasingly recognized as key players in the ocean carbon cycle. GZ spans multiple trophic levels and thrives in diverse marine habitats. Although there are uncertainties, GZ populations may be expanding globally due to changing ocean conditions, potentially exerting large-scale impacts on marine ecosystems. Although historically underappreciated, recent studies indicate that GZ contributes significantly to carbon sequestration, facilitating particulate organic carbon (POC) export through the sinking of carcasses, fecal pellets, and the formation of marine snow.
This session will explore the multifaceted roles of diverse GZ in vertical carbon export, their impact on biogeochemical processes, and how their unique interactions with microbial communities influence nutrient cycling. We invite contributions from experimental, observational, and modeling studies that shed light on GZ-mediated carbon fluxes, their ecological and biogeochemical importance, and their potential to reshape the biological carbon pump. Insights into GZ contributions to the soft-tissue pump, microbial loop dynamics, and carbon storage are particularly encouraged.
Additionally, we welcome new surveys and methodologies, including metabarcoding and omics techniques, to improve understanding of GZ diversity and their ecological roles. Innovative approaches to monitoring GZ through remote sensing, drones, ROVs, and citizen science, alongside advancements in ecosystem modeling, are highly welcomed. This session aims to bridge gaps in our understanding of GZ's role in past and future oceanic changes and their broader implications for marine ecosystem services. By advancing our knowledge of GZ ecology and their contributions to the global carbon cycle, this session aims to enhance the integration of GZ into biogeochemical models and improve predictions of ocean carbon storage.

Convener: Aino Hosia | Co-conveners: Tinkara Tinta, Dhugal Lindsay, Sarah Lou Carolin Giering
OS3.3 EDI

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

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

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

Co-organized by BG8
Convener: Ruth Parker | Co-conveners: Lucas PorzECSECS, Natalie Hicks, Mark Coughlan, Sarah Paradis
OS3.4 EDI

The combined effects of climate change and anthropogenic pressures threaten marine ecosystems, coastal human activities, with significant implications for safety, economy, marine biodiversity, and habitat integrity.
To sustain both ecosystem functioning and ocean-based economic activities, knowledge and forecast in the framework of climate research (WMO), the 2021-2030 UN Ocean Decade and the G7 Future of the Seas and Oceans Initiative have identified as an absolute priority the increase of a sustained, multi-disciplinary integrated ocean observing systems.
Integrated observing systems require data both by global (e.g. GOOS, EMODNET) and regional observation systems to be assimilated into numerical and statistical models, but their sustainability depends on the development of cost-effective technologies to improve the observing capacities (including spatial and temporal resolution) and reduce the costs of observations, aiming for a ‘’more environmentally sustainable ocean observing system”.
The session focuses on marine ecosystems, technological developments for the study of abiotic and biotic factors, with a focus on anthropogenic impacts, climate drivers, and other key indicator/proxies. Multidisciplinary approaches using data coming from multiple sources are encouraged. Integration of mathematical models, in-situ and remote observations is suggested with the aim to develop methods, technologies and best practices to restore, improve resilience, monitor biodiversity and to guarantee sustainable use of marine resources.
The following topics will be discussed: effects of pollution on biota considering their natural and anthropogenic sources; global change effects on marine ecosystem; marine ecosystem restoration; new technology development; advanced methods for collection, data processing, data curation, and information extraction; benthic and pelagic community dynamics; economic evaluation of natural capital.

Convener: Marco Marcelli | Co-conveners: Daniele Piazzolla, Xiaoxia Sun, Shan Zheng, Yéssica Contreras Pacheco
OS3.5 EDI

The North Sea, one of the most well-observed and heavily exploited shelf sea regions, faces substantial challenges due to climate change, with far-reaching effects on food security, ocean health, and through feedback effects, on the climate system. To address these pressing issues, it is crucial to understand the complex and dynamic processes driving the North Sea system and their future evolution. The North Sea's extensive spatiotemporal observational coverage provides a unique opportunity to study the effects of climate change on the coastal ocean. This session aims to bring together multidisciplinary perspectives to address the current state, future threats such as compound extremes, and other critical issues affecting the North Sea. We invite submissions from observational and modelling studies across multiple disciplines, including physics, chemistry, and biology, that address, but are not limited to, the following topics related to the North Sea: primary production, biogeochemical cycling of nutrients and oxygen, the ocean carbon cycle, carbon dioxide removal technologies (CDR), monitoring, reporting and verification of CDR, ocean acidification, climatic variability, extreme events, circulation patterns, land-ocean interactions, biophysical interactions, sediment dynamics, marine ecology and biodiversity, and socio-economic impacts and ecosystem services.

Convener: Andrea van Langen RosónECSECS | Co-conveners: Alizée Roobaert, Arthur Capet, Matthew Humphreys, Vlad Macovei
OS3.6

Many key ocean variables are defined by consensus without a clear linkage to the international system of units (SI). As the amount of data from diverse sources and platforms increases, measurement bias and discrepancies in signal-to-noise-ratio emerge, complicating the detection and quantification of Global Change effects. Thus, metrology (the science of measurements) becomes increasingly important. This session invites studies that evaluate the impact of instrument calibration, metrological traceability, and the use of reference materials on marine biogeochemical measurements. Focus areas include the seawater carbonate system, dissolved inorganic nutrients, dissolved oxygen, and carbon and oxygen isotopes. This session will discuss how accurate calibration enhances data reliability, improves reproducibility, and drives scientific advancements in marine biogeochemistry. The session will promote dialogue between metrologists, oceanographers and manufacturers to shape a future where data legacy is guaranteed.

Co-sponsored by IAPSO and BIPM
Convener: Maribel I. García-Ibáñez | Co-conveners: Marta Álvarez, Tobias Steinhoff, Matthew Humphreys
BG1.7 EDI

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

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

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

Co-organized by OS3/SSS5
Convener: Nelly Sophie RaymondECSECS | Co-conveners: Julian Helfenstein, Sonya Dyhrman, David O'Connell, Tom Jilbert
BG2.6 EDI

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

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

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

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

Co-organized by OS3/SSS5
Convener: Carsten SimonECSECS | Co-conveners: Hannelore Waska, Hongyan Bao, Gonzalo Gomez Saez, Sinikka Lennartz
BG7.1 EDI

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

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

Co-organized by ERE4/OS3
Convener: Helge Niemann | Co-conveners: Alina Stadnitskaia, Tina Treude, Claudio Argentino
ERE4.6 EDI

Pyrite is the most common sulphide in the Earth’s crust and occurs in many different types of rock. Following many decades of research, the morphology, trace element and isotopic composition of pyrite can be used to reconstruct a range of bio- and geological processes across a broad spectrum of scales.
In the oceans, pyrite is the dominant sink for reduced sulphur and is intimately connected to biological pathways of sulphate reduction, meaning the formation and isotopic composition of pyrite can be used to reconstruct the redox architecture of ancient marine environments. As a major gangue mineral phase in hydrothermal ore deposits, the formation and geochemistry of pyrite can be used to investigate and potentially detect ore forming processes. At the other end of the life-cycle, the weathering of pyrite during acid mine drainage and subsurface geological storage is a major environmental concern.
This session will bring together scientists investigating pyrite across a range of physico-bio-geochemical conditions in various earth science disciplines e.g. nuclear waste, ore deposits or acid mine drainage. Our aim is to foster intradisciplinary knowledge transfer of experiences between different research areas. We invite contributions presenting geochemical field studies, in-situ and laboratory investigations of rocks and formations as well as numerical simulation studies within the given context.

Co-organized by GMVP5/OS3
Convener: Michael Kühn | Co-conveners: Alwina Hoving, Joseph Magnall, Daniel Smrzka
AS2.5 EDI

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

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

Co-organized by BG4/OS3, co-sponsored by SOLAS and GESAMP WG38
Convener: Parvadha Suntharalingam | Co-conveners: Maria Kanakidou, Damian Leonardo Arévalo-Martínez, Manuela van Pinxteren, Liselotte Tinel

OS4 – Global ocean processes and oceanographic techniques

Sub-Programme Group Scientific Officer: Aida Alvera-Azcárate

OS4.1 EDI | PICO

This open PICO session welcomes presentations on all aspects of ocean processes and oceanographic techniques that are not covered in specialised sessions, as well as advances due to new instruments and techniques such as gliders and autonomous vehicles. This includes all marine disciplines as well as interaction of the ocean with the atmosphere and/or the cryosphere. Global studies and topics that have global relevance are welcome (i.e. both open ocean and shelf seas). Studies focusing on ocean processes might include turbulent mixing, phytoplankton bloom characterisation, or air-sea interactions, for example. Studies about the development of new oceanographic techniques might include robotics, design of numerical models or parameterisations, applications of novel instrumentation, or novel applications of traditional technology.

Convener: Karen J. Heywood | Co-conveners: Sabrina Speich, Marcel du Plessis
OS4.2 EDI

Marine extreme events, including phenomena such as storm surges, marine heatwaves, harmful algal blooms, jellyfish blooms, acidification, severe storms and temporally or spatially compounding events are becoming increasingly frequent under climate change. These events have significant impacts on marine ecosystems, coastal communities and global economies. Despite their profound socio-economic and environmental impact, extreme events in the marine environment remain largely understudied, poorly understood and difficult to simulate, making them difficult to predict. The dynamics of these events span a broad range of spatial and temporal scales and are often influenced by complex feedback mechanisms between the ocean and other components of the climate system. Fundamental research remains crucial in enhancing our understanding of these phenomena and in predicting their occurrence and related risks.

This session encourages contributions addressing dynamic mechanisms across an entire spectrum of atmospheric and ocean extremes, event attribution studies and projections under future climate. Relevant submissions also encompass new observation techniques, new modeling and machine learning methods to marine extremes forecasting, novel detection strategies and, finally, ecosystem or socio-economic impact assessments, relevant for prevention, mitigation and adaptation policies.

Convener: Antonio Ricchi | Co-conveners: Coline Poppeschi, Giovanni Liguori, Matjaz Licer, Baptiste Mourre
OS4.3 EDI

Marine heatwaves (MHWs) are prolonged and extreme warm ocean conditions that cause substantial ecological and socio-economic damage. Understanding of the physical mechanisms that generate MHWs is important to improving our capacity to forecast them. Meanwhile, gaining a better understanding of the impacts of MHWs on ecosystems, and their interactions with other parts of the climate system, is significant for promoting sustainable development in the face of climate change. We welcome abstract submissions across all aspects of marine heatwave research and particularly encourage studies of the following themes:

- Definition and Methods: novel physics and impact-based definitions which challenge the now-traditional statistical framework; observational and modelling requirements; spatial and temporal evolution); AI/ML-based detection; local/coastal to regional/global scales.
- Impacts: Socio-economic damage to marine activities and industries including but not limited to tourism, fisheries, aquaculture; discussions with stakeholders.
- Mitigation/Adaptation: forecasting efforts on short-term to decadal timescales; projections of future changes; studies of precursors and predictability.
- Interactions: compound and concurrent events, ecosystem and biogeochemical implications (e.g. on nutrient/oxygen availability and trophic web), impact on atmospheric circulation/weather.

Convener: Ronan McAdamECSECS | Co-conveners: Ana Oliveira, Saurabh Rathore, Emanuele Organelli, Neil Holbrook
OS4.4

Advanced remote sensing capabilities have provided unprecedented opportunities for monitoring and studying the ocean environment as well as improving ocean and climate predictions. Synthesis of remote sensing data with in situ measurements and ocean models have further enhanced the values of oceanic remote sensing measurements. This session provides a forum for interdisciplinary discussions of the latest advances in oceanographic remote sensing (using electromagnetic or acoustic waves) and the related applications and to promote collaborations.

We welcome contributions on all aspects of the oceanic remote sensing and the related applications. Topics for this session include but are not limited to: physical oceanography, marine biology and biogeochemistry, biophysical interaction, marine gravity and space geodesy, linkages of the ocean with the atmosphere, cryosphere, and hydrology, new instruments and techniques in ocean remote sensing, new mission concepts, development and evaluation of remote sensing products of the ocean, and improvements of models and forecasts using remote sensing data. Applications of multi-sensor observations to study ocean and climate processes and applications using international (virtual) constellations of satellites are particularly welcome.

Convener: Aida Alvera-Azcárate | Co-conveners: Craig Donlon, Cristina González-Haro, Tong Lee, Adrien Martin
OS4.5 EDI

To investigate the routes and endpoints of marine contaminants such as anthropogenic hydrocarbons, heavy metals, marine litter, including plastics and e-waste, HNS, POPs, radionuclides, PFAS, pharmaceutics, etc., oceanographic monitoring and models are widely applied. This session covers monitoring strategies, lab studies, computational tools, and web-based applications to track marine pollutants and their effects at the local, regional, and global levels. Advanced observational techniques, protocols, and toxicity testing; ensemble and multi-model simulations; machine learning and artificial intelligence applications are among the subjects that are being solicited.

Studies linking effects to broader ecosystem stressors, such as climate change and environmental degradation, are particularly welcome. Increased anthropogenic pressure in the Arctic Ocean resulting from the melting of polar ice makes researching marine pollutant transfer under ice conditions extremely valuable.

The session's key questions are: What do we know about sources of marine pollution? Which factors affect the dispersion of pollutants in the marine environment? What happens to the contaminants in the water column, sediments, and on the sea surface? How do marine pollutants interact with marine ecosystems?

The impact of other environmental stressors such as artificial light, noise, and thermal pollution on marine ecosystem resilience is also a significant topic for discussion.

Convener: Svitlana Liubartseva | Co-conveners: George Zodiatis, Sebastien Legrand, Luisa Galgani, Panagiota Keramea
OS4.6

Argo is one of the Global Ocean Observing System components. Initiated in the late 90s in the context of GODAE (the Global Ocean Data Assimilation Experiment) and CLIVAR (Climate and Ocean: Variability, Predictability and Change) to provide in situ measurements of temperature and salinity in the upper 2000m of the global ice-free ocean, Argo has always had a strong connection with ocean predictions.

OneArgo is the ongoing extension of the Argo array into seasonal ice zones, marginal seas, deeper waters (Deep-Argo) and biogeochemical parameters (BGC-Argo). The aim of the Argo programme is to achieve the full implementation of this new ambitious global, full-depth and multidisciplinary OneArgo array by the end of the UN Ocean Decade (2030).

The session focuses on the use of Argo data in physical and biogeochemical ocean monitoring, forecasting and reanalysis systems. It covers the use of Argo data for model parameter optimization, model trajectory correction through data assimilation, verification/validation activities, field reconstruction through AI methods, and model/data fusion (e.g., bias correction, AI tools). The session also covers design studies such as results from Observing System Experiments and Observing System Simulation Experiments. Specific focus will be put on highlighting the role of Deep-Argo and BGC-Argo data, and synergies between OneArgo and other observing systems. Contributions are also expected from research teams involved in the development and implementation of the OneArgo array in terms of design, data processing, and novel functionalities.

Convener: Claire Gourcuff | Co-conveners: Stephanie Guinehut, Birgit Klein, Gianpiero Cossarini
OS4.7 EDI

The Copernicus Marine Service provides regular and systematic reference information on the physical (including sea-ice and wind waves) and biogeochemical states of the global ocean and European regional seas. This capacity encompasses the description of the current ocean state, the prediction of the ocean state a few days ahead, and the provision of consistent retrospective data records for recent decades. In the coming years, Copernicus Marine will prepare the implementation of the next generation of ocean monitoring and forecasting systems and new services for the coastal ocean and for marine biology. Copernicus Marine will also progressively embrace the new capabilities of digital services in synergy with the European Digital Twin of the Ocean (DTO) developments. The European DTO will connect and interoperate, on a common digital platform, a large variety of ocean and coastal numerical tools, allowing for global, regional-to-coastal model configurations and the co-development of new simulations and what-if-scenarios for enhanced on-demand ocean forecasting and ocean climate prediction.
The session focuses on the main Copernicus Marine Service research and development activities on ocean modelling; data assimilation; processing of observations, impact and design of in-situ and satellite observing systems; verification, validation, and uncertainty estimates; monitoring and long-term assessment of the ocean physical and biogeochemical states. The session also includes research activities that are required to prepare the next generation of ocean monitoring and forecasting systems (improved Arctic monitoring, ensemble forecasting, higher resolution, regional ocean climate projections, use of artificial intelligence techniques) and new services for the coastal ocean and for marine biology. The session will also encompass research activities that are required for the development of the European DTO, including the next generation of ocean models combining artificial intelligence and high-performance computing, dedicated infrastructures and platforms as well as protocols and software and the definition of what-if-scenarios.
Presentations are expected from research teams involved in the Copernicus Marine Service, the European DTO, the development of downstream applications and in relevant Horizon Europe projects. Contributions from the international OceanPredict community and from the relevant UN Decade programmes and projects are strongly encouraged.

Convener: Stephanie Guinehut | Co-conveners: Anna Teruzzi, Julien Brajard, Benjamin Jacob, Andrea Storto
ITS1.2/OS4.8 EDI

Machine learning (ML) methods have emerged as powerful tools to tackle various challenges in ocean science, encompassing physical oceanography, biogeochemistry, and sea ice research.
This session aims to explore the application of ML methods in ocean science, with a focus on advancing our understanding and addressing key challenges in the field. Our objective is to foster discussions, share recent advancements, and explore future directions in the field of ML methods for ocean science.
A wide range of machine learning techniques can be considered including supervised learning, unsupervised learning, interpretable techniques, and physics-informed and generative models. The applications to be addressed span both observational and modeling approaches.

Observational approaches include for example:
- Identifying patterns and features in oceanic fields
- Filling observational gaps of in-situ or satellite observations
- Inferring unobserved variables or unobserved scales
- Automating quality control of data

Modeling approaches can address (but are not restricted to):
- Designing new parameterization schemes in ocean models
- Emulating partially or completely ocean models
- Parameter tuning and model uncertainty

The session welcomes also submissions at the interface between modeling and observations, such as data assimilation, data-model fusion, or bias correction.

Researchers and practitioners working in the domain of ocean science, as well as those interested in the application of ML methods, are encouraged to attend and participate in this session.

Convener: Julien Brajard | Co-conveners: Aida Alvera-Azcárate, Redouane Lguensat
ITS1.19/OS4.9 EDI

NASA successfully launched the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission on February 8, 2024. The spacecraft carries three groundbreaking instruments: the Ocean Color Imager (OCI), the Hyper-Angular Rainbow Polarimeter #2 (HARP 2), contributed by the University of Maryland Baltimore County, and the Spectro-polarimeter for Planetary Exploration (SPEXone), contributed by the Netherlands. This mission makes simultaneous measurements of the optical properties of water bodies, land, and the atmosphere that are first of their kind. This interdisciplinary session invites research on oceans, lakes, land, aerosols, and clouds, covering topics such as radiative transfer theory, algorithm development (including machine learning), validation, ocean and aquatic system biogeochemistry, terrestrial processes, and atmospheric process studies. Submissions demonstrating the connections between the atmosphere, ocean/aquatic systems, and land, as well as the synergistic use of PACE’s three sensors, are highly encouraged. We welcome the submissions that are using data collected during PACE validation campaigns (e.g., PACE-PAX). The session aims to strengthen collaboration across disciplines to fully utilize PACE’s unique dataset.

Convener: Ivona Cetinic | Co-conveners: Skye Caplan, Otto Hasekamp, Morgaine McKibben, Bastiaan van Diedenhoven
GI3.1

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

Co-organized by BG4/OS4
Convener: Pietro Tizzani | Co-convener: Andrea VitaleECSECS
GM8.1 EDI

Underwater landscapes, from shallow coastal zones to deep oceans, are shaped by geologic, biologic, oceanographic and anthropogenic processes. The resulting morphologies are manifold and their description and quantification provide critical insights into associated underlying processes. Many such processes act at multiple spatial and temporal scales, and their understanding is key for a safe and sustainable use of coastal regions and the assessment of offshore geohazards. This interdisciplinary session aims to examine the causes and consequences of processes shaping underwater landscapes, including erosional and depositional dynamics, gravitational driven and current-induced sediment transport, submarine landslides, active deformation, volcanic activity, fluid migration and escape, faulting and folding, and other processes responsible of seafloor geomorphic changes. Contributions to this session can include work from marine or lacustrine environments and all physiographic regions such as coastal oceans and marginal seas, oceanic plateaus, abyssal hills, mid-ocean ridges, accretionary wedges, continental shelves and margins. We welcome integrative studies that combine satellite-derived and hydroacoustic seabed characterizations, visual observations, seismic images of the sub-seafloor as well as sedimentary, geochemical, and geological seabed samples. Such interdisciplinary studies provide an exciting opportunity to integrate the approaches of geomorphology and geophysics, and to extend quantitative geomorphology offshore.

Co-organized by OS4/SSP3, co-sponsored by ILP and IAG
Convener: Jacob Geersen | Co-conveners: Alessandra Savini, Sebastian Krastel, Aaron Micallef, Luca Fallati
GM8.6 EDI

The phenomenon of “fluid venting” is globally recognized across various geodynamic contexts, leading to diverse surface morphologies such as pockmarks and mud volcanoes, as well as a range of geological, geochemical, and biological phenomena. Fluid venting involves the upward migration of fluids (including gas) due to subsurface overpressure and/or buoyancy through plumbing systems that are not yet fully understood. Sedimentary layers and geological structures (faults, fractures) can either facilitate or block fluid migration. Fluid seepage in shallow subsurface, increasing pore pressure in sediments, modifies the slope stability leading to landslides and, mutually, the presence of mass-transport deposits influences the location and morphology of fluid venting features.
Two main types of fluid vents are commonly distinguished: (i) “cold seeps,” which are characterized by low-temperature fluid emissions, and (ii) hydrothermal vents, where fluids emerge at temperatures between 200-400°C. In submarine settings, marine geophysical data of different bandwidths can be used to identify fluid-related features on the seafloor and the presence of gas in the water column, which appears as acoustic flares, and below the seafloor, as acoustic anomalies. These anomalies include focused or diffused acoustic turbidity and blanking, bright spots, high-amplitude reflections, chimney or pipe structures, and bottom simulating reflectors (BSRs) associated with gas hydrate.
Sampling and direct observation are also essential for assessing the chemosynthetic ecosystems thriving in these extreme environmental conditions. This session aims to explore the role of submarine fluid flow and venting in: (i) shaping the seafloor as a geomorphic process, (ii) driving other geological processes (i.e. slope instability) (iii) posing potential marine geohazards, and (iv) driving biological processes. Contributions are invited from any offshore region, ranging from continental shelves to abyssal plains, based on multi-scale datasets including hydro-acoustic imagery, 2D/3D seismic reflection data, samples, and ROV observations.

Co-organized by OS4
Convener: Daniele Spatola | Co-conveners: Giulia Matilde Ferrante, Marzia Rovere, Elena Scacchia, George Papatheodorou
ESSI4.6 EDI

Humans have been successfully mapping the remotest and most inhospitable places on Earth, and the surfaces and interiors of other planets and their moons at highest resolution. However, vast areas here on Earth remain blank spots and are located in areas that have not been accessed either through field surveys, geophysical methods or remote sensing due to technical and/or financial challenges. Some of these regions are crucial, as they hold the potential to uncover important geological and habitat information to facilitate future exploration efforts and an overall better understanding of our environment.
Such extreme and remote locations are commonly associated with the ocean floor, or planetary surfaces, but these extreme worlds might also be found in hot deserts, under the ice, in high-mountain ranges, in volcanic edifices, hidden underneath dense canopy cover, or located within the near-surface crust. All such locations are prime targets for remote sensing mapping in a wider sense. The methodological and technical repertoire to investigate extreme and remote locations is thus highly specialized and despite different contexts there are commonalities not only with respect to technical mapping approaches, but also in the way how knowledge is gathered and assessed, interpreted and visualised regarding its scientific but also its economic value.
This session invites contributions to this field of geologic mapping and cartography of extreme (natural) environments with a focus on the scientific synthesis and extraction of information and knowledge.
A candidate contribution might cover, but is not limited to, topics such as:
- ocean mapping using manned and unmanned vehicles and devices,
- offshore exploration using remote sensing techniques,
- crustal investigation through drilling and sampling,
- mapping campaigns in glaciated regions
- subsurface investigation using radar techniques,
- planetary geologic and geophysical mapping,
- geologic investigation of desert environments.
The aim of this session is to bring together researchers mapping environments that are hardly accessible or not accessible at all, thus often relying on geophysical or remote sensing techniques as main source for collecting data and information. We would like to focus on geological and geophysical mapping of spots for which we have no or only very limited knowledge due to the harsh environmental conditions, and we would thus exclude areas that are inaccessible for political reasons.

Co-organized by GM2/OS4/PS7
Convener: Anu Kaskela | Co-conveners: Kristine Asch, Anett Blischke, Marco Pantaloni
NH4.1 EDI

The assessment of the earthquake hazard and risk and the enhancement of the society’s resilience is greatly dependent on the knowledge of impact data sets of past earthquakes. For earthquakes that occurred in the historical period such data sets could be based on various types of historical documentation and in addition on geological observations and possibly on archaeological evidence. After the establishment and gradual improvement of macroseismic scales the earthquake impact data sets are translated to macroseismic intensity with the use of several methods and techniques. In the modern period the collection of macroseismic observations and the assignment of intensities has been expanded to the so-called citizen seismology. These new achievements are of significance to advance the methods that may contribute to the assignment of macroseismic intensities to historical earthquakes.
This session is devoted to the advancement of methods and techniques that may contribute to the compilation, storage and elaboration of impact data sets useful for the intensity characterization of historical earthquakes as well as for seismic hazard and risk assessment purposes. Welcomed to this session are also similar studies focusing on the collection and elaboration of impact data sets for other earthquake-related natural hazards, e.g. tsunamis and landslides, with the aim to help the assessment of hazards and risks.

Co-organized by OS4/SM8
Convener: Gianfranco Vannucci | Co-conveners: Ioanna TriantafyllouECSECS, Laura Gulia
NP2.1 EDI

The Earth system is a complex, multiphysics system with nonlinear interactions on multiple spatial and temporal scales. Understanding constituent processes (linear, nonlinear, stochastic, etc.) on the one hand, and the complexity of individual subsystems or the full integrated system on the other, is key to being able to better model the Earth System in a predictive fashion. The renaissance of machine and deep-learning in the past decade has led to rapid progress in the development of advanced approaches in, e.g., nonlinear time series analysis, dynamical and stochastic systems theory, complex systems theory, and these approaches in turn show promise in facilitating further advances in modeling the Earth system.

In this context, this session seeks contributions on all aspects of complexity, nonlinearity, and stochastic dynamics of the Earth system, including the atmosphere, the hydrosphere, the cryosphere, the solid earth, etc. Communications on theoretical, experimental and modeling studies are all welcome, where the latter modeling studies can span the range of model hierarchy from idealized models to complex Earth System Models (ESM). Studies based on emerging approaches such as data driven models, Artificial Intelligence approaches, complex network methods, dynamical and stochastic systems theory, etc., are particularly encouraged.

Co-organized by OS4
Convener: Naiming Yuan | Co-conveners: Christian Franzke, Balasubramanya Nadiga, Paul Williams, Da Nian
NP6.5 EDI

Gravity flows are driven by gravity because of a density different from that of the surrounding environment, often due to temperature (e.g. katabatic winds) and/or salinity (e.g. density currents) differences, and/or the presence of particles (e.g. snow avalanches, debris-flows turbidites, pyroclastic flows). This can be observed either as a current along a slope or as an intrusion in the bulk of a stratified environment. While occurring in various planetary environments, and involving different fluids and particles, they share numerous features due to the common and similar physical processes that govern their dynamics. Yet, a universal description of their dynamics remains elusive, as specifically the feedback on the flow of various processes, such as entrainment, fluid-particle interactions,
internal waves, etc., is difficult to predict.

This session then aims to present complementary physical-based approaches, by gathering researchers from different communities, all focusing on these flows by either studying field data, improving risk assessment techniques, using analogue laboratory experiments or numerical simulations, or focusing on analytical modelling. We therefore welcome contributions including (but not limited to):
- snow avalanches, dust storms, landslides, turbidity currents
- river, volcanic and oceanic plumes
- mud, debris and pyroclastic flows
- katabatic winds, oceanic density currents
-offshore waste discharge

We particularly encourage the participation of early-career researchers and students.

Co-organized by OS4
Convener: Yvan Dossmann | Co-conveners: Gauthier Rousseau, Claudia Adduce, Maria Eletta Negretti, Guillaume Carazzo
NP6.1 EDI

Join us for the third edition of the Lagrangian session, where researchers across disciplines showcase their work using Lagrangian tools and techniques on turbulent to planetary scales. In this session, you can expect to hear about the latest developments in Lagrangian techniques, learn about a wide range of topics and applications, and expand your professional network.

We invite presentations on topics including – but not limited to – the following:
- Large-scale circulation studies using direct Lagrangian modeling and/or age and chemical tracers (jets, gyres, overturning circulations);
- Exchanges between reservoirs and mixing studies (e.g. transport barriers and Lagrangian Coherent Structures in the stratosphere and in the ocean, stratosphere-troposphere exchange);
- Tracking long-range anthropogenic and natural influence (e.g. effects of recent volcanic eruptions and wildfire smoke plumes on the composition, chemistry, and dynamics of the atmosphere, transport of pollutants, dusts, aerosols, plastics, and fluid parcels in general, etc);
- Inverse modeling techniques for the assessment and constraint of emission sources (e.g. backtracking, including diffusion and buoyancy);
- Model and tool development, computational advances.

Co-organized by AS4/OS4
Convener: Louis RivoireECSECS | Co-conveners: Jezabel Curbelo, Silvia Bucci, François G. Schmitt, Ignacio Pisso
NP6.2 EDI

Geophysical and astrophysical flows in stratified media exhibit stratified turbulence that gives rise to a variety of flow phenomena spanning a range of spatial scales from the Kolmogorov to planetary scales. Stratified turbulence significantly influences the flow dynamics on various temporal scales via complex nonlinear interactions, which continue to be challenging to understand, diagnose, and quantify from both theory and numerics. This understanding is fundamental to advance our knowledge of turbulent flow dynamics, and a prerequisite for improved turbulent closures and parameterizations for robust predictions of weather and climate. This session aims at bringing together the recent advancements in the field of fluid dynamics, with a focus on geophysical and astrophysical flows, as well as magneto-hydro dynamics.

Our session invites fundamental and applied contributions on stratified turbulence in fluids from theoretical, numerical, and experimental observational perspectives. The topics include, but are not limited to: two dimensional, three dimensional, isotropic, and anisotropic turbulence; energy transitions and cascades in turbulent flows; turbulent fluxes and transports; turbulent decay, mixing, and dissipation; stable boundary layer flows and intermittent turbulence; wave-vortex dynamics in various turbulent regimes; wave turbulence; clear air turbulence; turbulence in weakly and strongly stratified flows and stratified shear flows.

We particularly encourage participation from early career researchers.

Co-organized by OS4/PS4
Convener: Manita ChoukseyECSECS | Co-conveners: Georg Sebastian Voelker, Mark Schlutow

OS5 – Short courses and Sessions of general interest for Ocean Science

Sub-Programme Group Scientific Officer: Johan van der Molen

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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
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Crafting and publishing papers is a crucial part of science communication, but it can be challenging. Whether you are working on your first draft, or perfecting your tenth, there can still be uncertainties about good writing and the publishing process. This course aims to provide early career scientists with straightforward guidelines for effectively communicating their research and, consequently, enhancing their prospects of successful publication. In this short course you will have the opportunity to meet editors of internationally renowned journals in the field of geoscience, hydrology and biogeoscience. After a short introduction of the editors, we will explore various facets of scientific writing and publishing, such as:
• How to start and improve an efficient writing process?
• What are the duties, roles and rights of editors, authors and reviewers?
• How to choose a suitable journal for your manuscript and what is important for early career authors?
• How to address reviewers' comments?
In this short course, there will be an opportunity to have an open discussion about how to make your manuscript ready for submission and navigate the peer-reviewing process. Together with the editors from different journals, we will explore other aspects, complementary to writing a paper, such as preparing the cover letters, choosing a suitable journal and understanding your rights as an author.
If you like to learn what is required to become a good peer-reviewer join the short course: Meet the Editors (3): How to peer-review - Fundamentals & EGU’s model. Both short courses can be attended independently.

Co-organized by GM12/OS5
Convener: Julia Schroeder | Co-convener: Faranak TootoonchiECSECS
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Peer-reviewing is the heart of quality control when it comes to publishing our scientific results. It is almost exclusively based on voluntary service by the scientific community itself. Yet peer-reviewers are currently the most limited human resource in scientific publishing. Insights about the peer-reviewing process are essential for the successful publication of your manuscript (if you are interested in more details, see also the short course “Meet the Editors (1 & 2): How to write, revise and publish your manuscript”), but the prospect of reviewing scientific manuscripts can appear daunting, especially to early career scientists. Open questions regarding the general role as reviewer, expectations by the journal editors, the degree of detail and pitfalls, but also ethical responsibilities may lead to doubts. This short course offers the opportunity to meet editors of internationally renowned journals – among others, from EGU journals – to get answers to those questions and to eliminate the doubts for one’s eligibility/aptitude as a reviewer:
• How is the peer-review process organized? How do editors search for and select reviewers?
• What are (and are not!) the duties and roles of reviewers?
• What are the ethical responsibilities as reviewer? How do I deal with conflict of interests?
• What are the benefits of voluntary peer-reviewing?
• Tips for my first review: What to focus on and how to structure?
• What are the dos and don’ts for appropriate peer-reviewing?
• What help can I get during the peer-review process?
Subsequently, the EGU peer-review model is presented as well as the details that are specific to the EGU journals. This includes the advantages of the EGU’s interactive open access publishing with multi-stage open peer review, as compared to traditional journals with closed peer review. Participants will have the opportunity to indicate their interest in the next edition of the EGU Peer Review Training (Fall 2025), where hands-on experience will be provided including reviewing preprints on EGUsphere, to complement the theory learned in the course. Participants who successfully complete the full training will be added to the reviewer data base for the EGU journals, so that they are visible to the journal editors and can efficiently contribute to the dissemination of high-quality science.

Co-organized by GM12/OS5
Convener: Janek Walk | Co-conveners: Eduardo Queiroz Alves, Rachel Oien, Barbara Ervens, Melissa Reidy
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The scientific communication landscape in the digital era is rapidly becoming all about effectively delivering ideas in brief. As scientific conferences move from longer physical meetings to more condensed hybrid formats, not only are short presentations necessary for pitching yourself to senior scientists or your next entrepreneurial venture to Venture Capitalists, but also for promoting your research. The opportunities of networking rarely reveal themselves, unless you are able to tell a brief, informative, and compelling story about you and your research.
It is truly an art to engage people through these short presentations and ignite a fire in their hearts, which will burn long enough for them to remember you and reach out to you later about relevant opportunities. While practice makes perfect is the mantra for delivering power-packed short presentations, there are several tricks to make your content stand out and set yourself apart from the crowd.
In this hybrid format course, we will bring together ideas and tips from years of sci-comm experience to provide you a one stop shop with the tricks of the trade. Finally, a hands-on exercise where participants will receive structured feedback on all aspects of their talk will help solidify the learning outcomes. The learning objectives of this short course are as follows:
Structuring a killer elevator pitch – learning from 1/2/3-min examples
3 minute
2019 Monash 3MT Winner - Beatrice Chiew, Pharmacy and Pharmaceutical Sciences
Three Minute Thesis (3MT) 2013 QUT winner - Megan Pozzi
Knowing your audience – harnessing the power of tailored openings/closings
Captivating delivery – leveraging body language to your advantage
TED Talk: How to speak so that people want to listen: https://youtu.be/eIho2S0ZahI
Harnessing creativity - choosing the right medium
Enunciating to engage – communicating across borders
Effectively practising your pitch – making the best of your time + confidence (maybe also acting training - presentations are performances)
Early career and underrepresented scientists are particularly encouraged to participate as they can gain the most from the learning outcomes of this short course.

Co-organized by GM12/OS5
Convener: Antara DasguptaECSECS | Co-conveners: Hannah Cloke, Hazel Gibson, Simon Clark
SC 3.3 EDI

Transdisciplinary research offers a powerful approach to tackling complex challenges in natural hazards and risk management, but it also presents unique challenges, particularly for early career scientists and practitioners. This short course is specifically designed to equip early career participants with practical tools and strategies for effectively engaging in and contributing to transdisciplinary projects. By focusing on the cross-fertilisation of hard and social sciences, the course will provide actionable insights into how to communicate across disciplines, deliver impactful research, and find common ground for collaboration. Participants will engage in hands-on activities and discussions, drawing from the experiences of leading projects such as The HuT (https://thehut-nexus.eu), PARATUS (https://www.paratus-project.eu), MYRIAD (https://www.myriadproject.eu), and DIRECTED (https://directedproject.eu). Attendees are also welcome to join the scientific session and splinter meeting that are part of this unified path, allowing them to choose between engaging in the entire programme or specific parts according to their interests.

Co-organized by GM12/NH12/OS5
Convener: Maria Vittoria GargiuloECSECS | Co-conveners: Gaetano Pecoraro, Cicilia Steffi Lukman, Julius Schlumberger, Janne Parviainen
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Building a successful academic career is challenging. Doing so while also raising a family can push you to your limits. Many early- and mid-career scientists grapple with balancing family life and academic responsibilities. The fear-of-missing-out dualism between family and academia causes an inner conflict and feeling of injustice and inadequateness. Families often find themselves confronted with what feels like a personal problem when, in reality, it is a shared societal issue. Modern families come in diverse forms, including dual-career parents, single parents, same-sex parents, and various shared parenting arrangements. The academic world must recognize and adapt to this reality, aligning with broader themes of inclusion, participation, and diversity.

It is crucial to find support and confidence in moving forward as an individual while remaining aligned with your personal values and goals. As a community, we need to openly discuss parenting in academia so that we can demand and develop sustainable solutions that benefit everyone, rather than repeatedly fighting private battles to follow the academic career dream. Parenthood can also shift your priorities, which may lead you to consider leaving academia altogether.

This short course provides a platform that allows an honest exchange on diverse experiences and continue the discussion from previous EGU General Assemblies on this topic. It will:
1. Provide insight into how being a parent impacts everyday academic life.
2. Present scientific studies on parenting in academia and explore the varying cultural and societal experiences.
3. Highlight personal experiences made by a panel of current and previous academic parents.
4. Conclude with an open discussion addressing public discourse on equal parenting and work-life balance.
This course is intended for scientists considering starting a family, current academic parents seeking to connect, and faculty staff responsible for supporting parenting employees.

Co-organized by GM12/OS5
Convener: Johanna Kerch | Co-conveners: Rebekka Steffen, Gerald Raab, Bart Root, Katrin Löer
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In this short course we will address the increasing role of artificial intelligence (AI) in geoscientific research, guiding participants through the various stages of the research process where AI tools can be effectively implemented, however with responsibility. We will explore freely available AI tools that can be used for data analysis, model development, and research publication. Additionally, the course aims to provoke reflections on the ethical implications of AI use, addressing concerns such as data bias, transparency, and the potential for misuse. Participants will engage in interactive discussions to explore what constitutes responsible and acceptable use of AI in geoscientific research, aiming to establish a set of best practices for integrating AI into scientific workflows.

Co-organized by EOS4/AS6/ESSI1/GM12/OS5
Convener: Edoardo MartiniECSECS | Co-convener: Fernanda DI Alzira Oliveira Matos
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The European Research Council (ERC) is a leading funding body at European level. It aims to support excellent investigator-driven frontier research across all fields of science. The ERC offers various outstanding funding opportunities, including grant budgets for individual scientists of up to €3.5 million. ERC calls are open to researchers around the world: all nationalities of applicants are welcome for projects carried out at a host institution in European Union member states or/and associated countries. At this session, the main features of ERC funding will be presented, including the recent changes implemented in the work programme concerning the evaluation process. Furthermore, two invited speakers, a current ERC grantee and a former member of the evaluation panel, will provide different perspectives of their experience with the ERC evaluation.

Co-organized by GM12/OS5
Convener: David Gallego-Torres | Co-conveners: Claudia Jesus-Rydin, Eystein Jansen
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Global challenges, such as climate change and natural hazards, are becoming increasingly complex and interdependent, and solutions have to be global in scope and based on a firm scientific understanding of the challenges we face. At the same time, Science and technology are playing an increasingly important role in a complex geopolitical landscape. In this difficult setting, scientific collaboration can not only be used to help address global challenges but also to foster international relations and build bridges across geopolitical divisions. Science diplomacy is a broad term used both to describe the various roles that science and researchers play in bridging geopolitical gaps and finding solutions to international issues, and also the study of how science intertwines with diplomacy in pursuing these goals


During this Short Course, experts will introduce key science diplomacy concepts and outline the skills that are required to effectively engage in science diplomacy. They will also provide practical insights on how researchers can actively participate in science diplomacy, explore real-life examples of science diplomacy, and highlight resources where participants can learn more about science diplomacy moving forward.

This Short Course is of interest to researchers from all disciplines and career levels.

Co-organized by EOS4/GM12/OS5
Convener: Lene Topp | Co-conveners: Chloe Hill, João Bettencourt
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
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
EOS2.3 EDI

“The truth is almost ten years since the Paris Agreement was adopted, the target of limiting long-term global warming to 1.5 degrees Celsius is hanging by a thread.
"The truth is the world is spewing emissions so fast that by 2030, a far higher temperature rise would be all but guaranteed. …
"Now is the time to mobilise, now is the time to act, now is the time to deliver. This is our moment of truth.” (Guterres, 2024)

One of the surest ways to mobilise, to act and deliver is through geo-education, geo-communication and geoethics. Humanity is dependent on both the climate and the ocean, and on their interaction. The danger of climate and ocean change can be applied, mutatis mutandis, to related threats, such as biodiversity, pollution, food security and fossil-fuel-driven war. Humanity appears to be in the grip of manic growth and ecological overshoot.

Far greater numbers of citizens than is currently the case need to increase their knowledge and communication skills in climate and ocean change and their underlying causes. This is achieved through a broad variety of methods: encounters, meetings, field trips, associations, classes, publications, peer pressure, workshops, geoethical awakening, social media, direct experience of extreme weather, association memberships, legal action and so on.

We welcome abstracts on a broad range of topics, from hands-on geo-communication of all kinds, through pedagogical ideas and practices, best practices, research, programme implementation and activism. Come and share your experience, your ideas, your anger, your vision, your research, your drive, your actions, your successes – from hands-on pedagogical ideas and practices, through geo-communication, curriculum matters and research, to policy and its implementation.

This session is organised in parallel to, but independently of, the special issue of the EGU journal *Geoscience Communication*, see https://gc.copernicus.org/articles/special_issue1271.html. You are invited to submit an article; be in touch directly with David.

Co-organized by CL3.2/GM11/OS1/OS5, co-sponsored by IAPG
Convener: David Crookall | Co-conveners: Giuseppe Di Capua, Svitlana Krakovska, Rachel Wellman, Pimnutcha Promduangsri
EOS3.1 EDI

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

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

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

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

Co-organized by AS6/BG0/GD11/GM11/OS5/PS0/SSS12, co-sponsored by AGU and JpGU
Convener: Claudia Jesus-Rydin | Co-conveners: Stefanie Kaboth-Bahr, Alberto Montanari, Hori, S. Rie, Billy Williams
EOS4.3

Geoethics is essential for tackling global human-caused changes. It integrates ethical considerations into geoscience, improving policy and decision-making. Geoscientists must provide accurate, transparent, and unbiased data to policymakers, ensuring decisions reflect environmental, social, and economic impacts. In times of rapid climate change, resource overexploitation, increasing risks, and environmental damages, geoethics promotes sustainable, just, and respectful geoscience practices. This framework encourages scientifically sound, socially responsible, and environmentally sustainable actions, building trust between scientists, policymakers, and the public through transparency, accountability, and community engagement. In practical terms, integrating geoethics into policymaking and decision-making involves:

a) Building Trust: Highlighting the importance of transparency, accountability, and community engagement in fostering trust between scientists, policymakers, decision-makers, and the public.
b) Transparent Communication: Clearly sharing scientific findings and uncertainties with all stakeholders to support informed and democratic decision-making.
c) Inclusive Practices: Involving local communities, indigenous peoples, and marginalized groups to ensure their voices are heard and their rights respected in geoscientific work.
d) Sustainable Solutions: Focusing on long-term sustainability over short-term gains to ensure resource extraction and land use do not compromise future generations' needs.
e) Interdisciplinary Collaboration: Working with other fields like sociology, economics, and political science to address complex environmental issues holistically.
f) Geoscience Education: Training young people to understand Earth system complexities and prepare the next generation of geoscientists to address global challenges.

By fostering a culture of ethical responsibility, geoscience can guide actions that mitigate adverse effects, promote resilience, and contribute positively to society. Ultimately, geoethics strengthens the capacity of geoscience to inform and influence policy, fostering a more sustainable and equitable future for all.
This session aims to collect and stimulate discussions about ideas, initiatives, project outcomes, tools (including new technologies), and case studies that highlight the positive contributions (as well as exemplify failures) of geoscientists in informing the decision-making and policy-making processes.

Co-organized by ERE1/GM11/OS5/SSS12, co-sponsored by IAPG
Convener: Silvia Peppoloni | Co-convener: Giuseppe Di Capua
EOS4.1 EDI

Evidence-based policymaking aims to ground public policies in the best available research and data, ensuring that decisions are informed by robust evidence rather than by ideology, assumptions, or political considerations. To support and inform policy, stakeholders need to engage in a way that addresses needs and develops solutions. To ensure this engagement is effective, it is important to identify the most effective formats for engagement to ensure re-searchers contributions enrich and strengthen local, national or international policy.
This session aims to show how research activities and outputs may impact society and policy beyond the academic world. It will highlight stories of success and failure from scientists who have engaged in policy or other activities that made critical societal impacts – either on an international, European, national, or local level – across different geoscience disciplines. Equally important, the session will also present the role of those working from within political institutions who have facilitated successful science-society-policy-dialogues. It will also aim to examine the various challenges that researchers face when engaging on the science-society-policy interface and various strategies that others have taken to manage and overcome them.

This session is relevant for researchers, policymakers, and those working on the interface from all career levels and science disciplines and will provide space for follow-up questions and a discussion with the participants at the session and at a splinter meeting during EGU25 week.

Co-organized by GM11/OS5/SSS12
Convener: Marie Heidenreich | Co-conveners: Maria Vittoria Gargiulo, Aoife Braiden, David Gallego-Torres, Georg Sebastian Voelker
EOS4.4 EDI

Despite an ever-growing body of scientific literature outlining the need for radical transformations, efforts to address the climate and ecological crisis keep falling painfully short of what is necessary. At the same time, the situation continues to worsen as global warming gets dangerously close to 1.5 degrees. While the role of geoscientists has traditionally been to provide neutral information to be used by the public and policy makers, several studies pointed out that the main blockade to urgent climate action is not currently a lack of understanding or awareness or the situation (Oreskes, 2022, The trouble with the supply-side model of science) but rather opposition to necessary transformations by vested interests and powerful actors (Stoddard et al, 2021, Three decades of climate mitigation: Why haven’t we bent the emissions curve?). Our own institutions, universities, and research centers are also failing to rise to the challenge of this crisis and partly contribute to maintaining the status quo (Thierry et al, 2023, No research on a dead planet).
In that context, what role can geoscientists play to contribute to the urgent transformations necessary to mitigate the climate and ecological crisis? To explore this topic, we invite contributions that broadly address the following questions, whether from a theoretical perspective or through firsthand experiences:
– How to engage with civil society, stakeholders and policymakers to ensure that research findings lead to appropriate policies?
– How to assess and reduce the ecological footprint of scientific institutions?
– How to expand outreach and training efforts, in particular to enable under-represented actors, reduce power imbalances in climate politics, and oppose greenwashing?
– Should scientists engage in disruptive actions and civil disobedience to highlight the urgency of the situation, oppose destructive projects, and/or press on problematic actors?
– How can scientific institutions prevent reinforcing the status quo and instead contribute to radical transformations ?
In 2024, presentations considered: Outreach efforts towards policymakers or in rural areas, campaigns for universities to cut ties with the fossil industry, sustainable travel policies for researchers, strategies to debunk greenwashing, barriers to the public engagement of academics, and discussion about academic activism. We particularly encourage submissions presenting interdisciplinary work including social sciences.

Co-organized by GM11/OS5/SSS1
Convener: Elodie Duyck | Co-conveners: Odin Marc, Rosa Rantanen, Jean-Philippe Vidal, Paolo Colombo
ESSI2.15 EDI

Pangeo (pangeo.io) is a global community of researchers and developers that tackle big geoscience data challenges in a collaborative manner using laptop to HPC and Cloud infrastructure. This session's aim is:
to motivate researchers who are using or developing in the Pangeo ecosystem to share their endeavours with a broader community that can benefit from these new tools.
to contribute to the Pangeo community in terms of potential new applications for the Pangeo ecosystem, containing the following core packages: Xarray, Iris, Dask, Jupyter, Zarr, Kerchunk and Intake.

We warmly welcome contributions that detail various Cloud computing initiatives within the domains of Earth Observation and Earth System Modelling, including but not limited to:
- Cloud federations, scalability and interoperability initiatives across different domains, multi-provenance data, security, privacy and green and sustainable computing.
- Cloud applications, infrastructure and platforms (IaaS, PaaS SaaS and XaaS).
- Cloud-native AI/ML frameworks and tools for processing data.
- Operational systems on the cloud.
- Cloud computing and HPC convergence and workload unification for EO data processing.

Also, presentations using at least one of Pangeo’s core packages in any of the following domains:
- Atmosphere, Ocean and Land Models
- Satellite Observations
- Machine Learning
- And other related applications

We welcome any contributions in the above themes presented as science-based in other EGU sessions, but more focused on research, data management, software and/or infrastructure aspects. For instance, you can showcase your implementation through live executable notebooks.

Co-organized by AS5/CL5/GI1/OS5
Convener: Tina Odaka | Co-conveners: Anne Fouilloux, Alejandro Coca-Castro, Dean Summers, Ross A. W. Slater
ESSI4.3 EDI

The visualization and user-friendly exploration of information from scientific data is one of the main tasks of good scientific practice. But steady increases in temporal and spatial resolutions of modeling and remote sensing approaches lead to ever-increasing data complexity and volumes. On the other hand, earth system science data are getting increasingly important as decision support for stakeholders and other end users far beyond the scientific domains.

This poses major challenges for the entire process chain, from data storage to web-based visualization. For example, (1) the data has to be enriched with metadata and made available via appropriate and efficient services; (2) visualization and exploration tools must then access the often decentralized tools via interfaces that are as standardized as possible; (3) the presentation of the essential information must be coordinated in co-design with the potential end users. This challenge is reflected by the active development of tools, interfaces and libraries for modern earth system science data visualization and exploration.

In this session, we hence aim to establish a transdisciplinary community of scientists, software-developers and other experts in the field of data visualization in order to give a state-of-the-art overview of tools, interfaces and best-practices. In particular, we look for contributions in the following fields:

- Developments of open source visualization and exploration techniques for earth system science data
- Co-designed visualization solutions enabling transdisciplinary research and decision support for non-scientific stakeholders and end-users
- Tools and best-practices for visualizing complex, high-dimensional and high frequency data
- Services and interfaces for the distribution and presentation of metadata enriched earth system science data
- Data visualization and exploration solutions for decentralized research data infrastructures

All contributions should emphasize the usage of community-driven interfaces and open source solutions and finally contribute to the FAIRification of products from earth system sciences.

Co-organized by AS5/OS5
Convener: Tobias Kerzenmacher | Co-conveners: Lucile Gaultier, Christof Lorenz, Philipp S. Sommer, Berit Arheimer