This session focuses on variability in the ocean circulation and its role in the climate system. We welcome contributions on all aspects of ocean circulation from observations, models and theory, from microscales to global scales, from timescales of seconds to millennia, from air-sea exchanges to abyssal mixing, from coastal processes to the open ocean, from the tropics to the polar oceans, from global energy budgets to small-scale turbulence, on externally forced and on internal physical processes. We particularly encourage submissions on interactions of the ocean with the atmosphere and cryosphere and their role in weather extremes and abrupt climate change. In addition, we are excited to see submissions that do not fit to any of the other sessions, including studies on the Pacific Ocean.

Air-sea interactions play a key role in the climate system. The ocean and atmosphere are intricately linked through the exchanges of momentum, mass, and energy. This drives processes on a wide range of spatial and temporal scales, from localised extreme events to the global climate. Air-sea interactions can dramatically impact extreme events such as tropical cyclones, marine heat waves, high precipitation events, and sea storms. They also shape the large-scale oceanic and atmospheric circulation affecting, for example, mesoscale eddies, Western Boundary Currents, convective precipitation, the Intertropical Convergence Zone, and ocean CO2 uptake. The complexity of air-sea interactions makes it hard to disentangle the different mechanisms at play, identify the driving processes, and properly model and parametrize them. This often results in widespread and persistent biases in coupled ocean-atmosphere models. Improving our knowledge of the physical and biogeochemical processes involved, through modeling or observations, is of fundamental importance to deepen our understanding of the Earth system and to improve the reliability of future projections as well as weather and ocean forecasts. This session aims to gather research efforts on air-sea interaction on global and regional scales over multiple temporal scales from interdisciplinary studies, modeling efforts, satellite, and in situ observations. This includes but is not limited to: turbulent air-sea fluxes, mesoscale eddies impact on CO2 fluxes, SSTs coupling with the atmospheric dynamic, tropical cyclones and cyclogenesis, extreme events onset, intensification and decay, parametrization of air-sea interactions, biases in coupled models, thermal and currents feedback, sea-spray role in air-sea exchanges and cloud formation.

The ocean surface mixed layer mediates the transfer of heat, freshwater, momentum and trace gases between atmosphere, sea ice and ocean, thus playing a central role in the dynamics of our climate. This session will focus on the surface mixed layer globally, from the coasts to the pelagic ocean. We will review recent progress in understanding the key processes taking place in the mixed layer: dynamic processes such as surface waves, Langmuir circulations and turbulence, shear-induced mixing, internal waves, coherent structures, fronts, frontal instabilities, entrainment and detrainment at the mixed layer base, convection, restratification induce physical effects on this important layer. From a biogeochemical perspective, the physical dynamics of the euphotic layer, as well as biogeochemical processes affecting the cycling of carbon, micro- and macronutrients, production and degradation of trace gases as well as microbial dynamics from basic to higher trophic levels affect the layer’s role and sensitivity as part of the earth system. The improvement of the representation of surface mixed layer processes in numerical models is a complex and pressing issue: this session will bring together new advances in the representation of mixed layer processes in high resolution numerical models, as well as evaluation of mixed layer properties in climate models using most recent observational datasets. The coupling of the ocean and atmospheric boundary layers as well as the special processes occurring under sea ice and in the marginal sea ice zone will be given special consideration. This session welcomes all contributions related to the study of the oceanic mixed layer, independent of the time- and space scales considered. This includes small scale process studies, short-term forecasting of the mixed layer characteristics for operational needs, studies on the variability of the mixed layer’s physical and biogeochemical properties from sub-seasonal to multi annual time scales and mixed layer response to external forcing. The use of multiple approaches (coupled numerical modeling, reanalyses, observations, experiments) is encouraged.

The rapid decline of the Arctic sea ice in the last decade is a dramatic indicator of climate change. The Arctic sea ice cover is now thinner, weaker and drifts faster. Freak heatwaves are common. On land, the permafrost is dramatically thawing, glaciers are disappearing, and forest fires are raging. The ocean is also changing: the volume of freshwater stored in the Arctic has increased as have the inputs of coastal runoff from Siberia and Greenland and the exchanges with the Atlantic and Pacific Oceans. As the global surface temperature rises, the Arctic Ocean is speculated to become seasonally ice-free by the mid 21st century, which prompts us to revisit our perceptions of the Arctic system as a whole. What could the Arctic Ocean look like in the future? How are the present changes in the Arctic going to affect and be affected by the lower latitudes? What aspects of the changing Arctic should observational, remote sensing and modelling programmes address in priority?
In this session, we invite contributions from a variety of studies on the recent past, present and future Arctic. We encourage submissions examining interactions between the ocean, atmosphere and sea ice, on emerging mechanisms and feedbacks in the Arctic and on how the Arctic influences the global ocean. Submissions taking a cross-disciplinary, system approach and focussing on emerging cryospheric, oceanic and biogeochemical processes and their links with land are particularly welcome.
The session supports the actions of the United Nations Decade of Ocean Science for Sustainable Development (2021-2030) towards addressing challenges for sustainable development in the Arctic and its diverse regions. We aim to promote discussions on the future plans for Arctic Ocean modelling and measurement strategies, and encourages submissions on the results from IPCC CMIP and the recent observational programs, such as the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), which cosponsors this session.

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 also a modelling component. Another important issue is the interaction between the atmosphere and the ocean as well as the cryosphere with the ocean, and how this affects the climate.

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

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

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

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

This session invites contributions based on observations, modelling, theory, and palaeo proxy reconstructions in the Indian Ocean that focus on recent observed and projected changes in Indian Ocean physical and biogeochemical properties and their impacts on ecological processes, diversity in Indian Ocean modes of variability (e.g., Indian Ocean Dipole, Indian Ocean Basin Mode, Madden-Julian Oscillation) and their impact on predictions, interactions and exchanges between the Indian Ocean and other ocean basins, as well as links between Indian Ocean variability and monsoon systems across a range of timescales. We encourage submissions on weather and climate extremes of societal relevance in the Indian Ocean and surrounding regions, including evaluating climate risks, vulnerability, and resilience.

We also welcome contributions that address research on the Indian Ocean grand challenges highlighted in the IndOOS Decadal Review, and as formulated by CLIVAR, the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), the International Indian Ocean Expedition 2 (IIOE-2), findings informed by the Coupled Model Intercomparison Project v6 on past, present and future variability and change in the Indian Ocean climate system, and contributions making use of novel methodologies such as machine learning.

The Southern Ocean around the latitudes of the Antarctic Circumpolar Current is vital to our understanding of the climate system. It is a key region for vertical and lateral exchanges of heat, carbon, and nutrients, with considerable past and potential future global climate implications. The role of the Southern Ocean as a dominant player in heat and carbon exchanges as well as its response to changing atmospheric forcing and increased melting of Antarctic ice masses remains uncertain. Indeed, the sparsity of observations of this system and its inherent sensitivity to small-scale physical processes, which are not fully represented in current Earth system models, result in large climate projection uncertainties. To address these knowledge gaps, the Southern Ocean is currently subject to investigations with increasingly advanced observational platforms, and theoretical, numerical, and machine learning techniques. These efforts are providing deeper insight into the three-dimensional patterns of Southern Ocean change on sub-annual, multi-decadal, and millennial timescales, as well as potential future changes 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, ocean productivity, climate-carbon feedbacks, and ocean-ice-atmosphere interactions. We will also discuss how changes in Southern Ocean heat and carbon transport affect lower latitudes and global climate more generally.

Solicited speaker: Katherine R. Hendry

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? How does the Antarctic Slope Current interact with the continental shelf and connect the basins around the continent? What role do ice-related processes play in nutrient upwelling on the continental shelf and in triggering carbon export to deep waters? 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 and interactions between ice shelves, sea ice and the ocean. 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 and biological oceanography as well as contributions from the PALMOD project and the SCAR INSTANT program.

This session aims to showcase an exciting diversity of state-of-the-art advances in all aspects of paleoceanography and paleoclimatology. We invite studies ranging across organic and inorganic geochemistry, sedimentology, and paleontology from marine and terrestrial environments, as well as multidisciplinary and modeling studies reaching into the future. We invite contributions that provide insight into the evolution of the Earth on short and long timescales, including how studies of paleoclimate and drivers can inform our current climatic changes and the implications for future Earth.

Today, the Indian, Pacific and Southern Oceans and associated ocean gateways capture the complex intermediate and deep-water return pathways of the global thermohaline circulation. The Indo-Pacific Warm Pool (IPWP) acts as a low latitude heat source for the polar regions and is a crucial part in globally significant climatic systems like the Australasian Monsoon, Intertropical Convergence Zone (ITCZ), El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). This highlights the Indo-Pacific’s importance in deciphering past and future coupled ocean-atmosphere dynamics.
The Cenozoic also sees large reorganisation of the hydrographic and atmospheric fronts across the Southern Hemisphere (SH). These changes have significant consequences for icesheet build-up in Antarctica and ocean-atmosphere carbon cycling, with further implications for surface ocean dynamics and productivity. Characterisation of these fronts using sedimentary records, located in mid-to-high latitudes in the SH allow us to understand the sensitivity and interconnection between Antarctic icesheets and carbon cycle to frontal shifts.
This session explores the role of the Indian, Pacific and Southern Oceans and their gateways in global climate change and as a biogeographic diversity hot spot from the geological past to the present. To understand the Cenozoic evolution of these Oceans and associated low- and high-latitude (especially SH) gateways, we invite submissions on wide-ranging topics including paleoclimatology, palaeoceanography, sedimentology, palaeontology, and data-model comparisons. This session will examine how feedbacks between the IPWP, Australasian hydroclimate and tectonic and/or weathering processes affect the evolution of the global monsoons and the ITCZ. We also encourage marine and/or terrestrial multi-proxy studies, investigating Cenozoic teleconnections of both equatorial Indo-Pacific (e.g., ENSO/IOD) and high latitude SH processes (e.g., variability of hydrographic fronts).

Regional climate is often influenced by or connected to changes in remote locations, a phenomenon known as a teleconnection. Changes in the ocean, sea ice, atmosphere or land conditions in remote locations can trigger atmospheric or oceanic disturbances, which then propagate and influence the climate in one or multiple distant regions. These changes could be periodic modes of variability (such as ENSO, IOD, QBO, AMV, PDV etc.) or a response to anthropogenic forcing (such as the warming Western Tropical Pacific or the North Atlantic Warming Hole etc.). Fleshing out the teleconnections associated with such changes provides us with a clearer understanding of the variations in the climate of a particular region and may also provide a source of predictability. This session invites contributions that focus on this aspect of climate variability and yield new understanding on the origin, dynamics and predictive potential of teleconnections. The studies may be observational or modelling in nature and may be based on paleoclimatic time-scales, the historical period or future scenarios. Research on new methods to diagnose and understand teleconnections is also welcome.

Atmospheric circulation is unquestionably listed among the fundamental causes of weather and climate. The session is dedicated to all aspects of relationships between atmospheric circulation in different spatial scales and climate as well as environmental variables. Contributions concerning theoretical aspects of circulation classifications development and their applications in various tasks (climatological, and environmental), and different scales are particularly welcome as well as submissions on recent climate variability and change studied by tools of synoptic climatology.

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

In 2015, the UN Sustainable Development Goals and the Paris Agreement on climate recognized the deteriorating resilience of the Earth system, with planetary-scale human impacts constituting a new geological epoch: the Anthropocene. Earth system resilience critically depends on the nonlinear interplay of positive and negative feedbacks of biophysical and increasingly also socio-economic processes. These include dynamics and interactions between the carbon cycle, the atmosphere, oceans, large-scale ecosystems, and the cryosphere, as well as the dynamics and perturbations associated with human activities.

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

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

The Arctic Realm is changing rapidly and the fate of the cryosphere, including Arctic sea ice, glaciers and ice caps, is a source of concern. Whereas sea ice variations impact the radiative energy budget, thus playing a role in Arctic amplification, the Greenland Ice Sheet retreat contributes to global sea level rise. Moreover, through various processes linking the atmosphere, ice and ocean, the change in the Arctic realm may modify the atmospheric and ocean circulation at regional to global scales, the freshwater budget of the ocean and deep-water formation as well as the marine and terrestrial ecosystems, including productivity. The processes and feedbacks involved operate on all time scales and it require a range of types of information to understand the processes, drivers and feedbacks involved in Arctic changes, as well as the land-ocean-cryosphere interaction. In this session, we invite contributions from a range of disciplines and across time scales, including observational (satellite and instrumental) data, historical data, geological archives and proxy data, model simulations and forecasts, for the past, present and future climate. The common denominator of these studies will be their focus on a better understanding of mechanisms and feedbacks on short to long time scales that drive Arctic and subarctic changes and their impact on climate, ocean, and environmental conditions, at regional to global scales, including possible links to weather and climate outside the Arctic.

To address societal concerns over rising sea level and extreme events, understanding and quantifying the contributions behind these changes is key to anticipate potential impacts of sea level change on coastal communities and global economy. In this session, we address these challenges and we welcome contributions from the international sea level community that improve our knowledge of the past, present and future changes in global and regional sea level, extreme events and coastal impacts.
We focus on studies exploring the physical mechanisms for sea level rise and variability and the drivers of these changes, at any time scale (from high-frequency phenomena to paleo sea level). 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 also encouraged, as well as those discussing potential short-, medium-, and long-term impacts on coastal environments, as well as the global oceans.

Analysis of energy transfers between and within climate components has been at the core of many step changes in the understanding of the climate system. Large-scale atmospheric circulation, hydrological cycle and heat/moisture transports are tightly intertwined. Dynamics and radiative exchanges are linked at the global scale, through the net impact of cloud feedbacks, sea-ice albedo changes, surface absorption by vegetation.

In the Tropics, the zonal mean Hadley circulation determines meridional energy transports, while Rossby and planetary-scale waves modulate the energy exchanges carried by extratropical eddies. In the ocean, the role of Atlantic Meridional Overturning Circulation is essential for the heat budget of continental regions in the Northern Hemisphere: long-term oceanic and sea-ice variability is crucial to understand and predict the dynamics in high latitudes. Observational and model studies have indeed shown that the Arctic is very susceptible to climate change, and climate perturbations in the Arctic likely have wide-spread influence. High-latitude atmosphere, biosphere, oceans and cryosphere have experienced significant changes over the observational era. Hence, advancing the understanding of variability and change, governing mechanisms and global implications, improving predictions and projections of high latitude climate in both hemispheres is highly important for global society.

We invite submissions on the interplay between Earth’s energy exchanges and the general circulation through modeling, theory, and observations, on the forced response and natural variability of the general circulation, understanding present-day climate, past and future changes, impacts of global features and change on regional climate. This session also aims to improve knowledge and representation of the multi-scale mechanisms that control high-latitude climate variability and predictability in both hemispheres from sub-seasonal to multi-decadal and longer time scales. We thus invite contributions on the causes, mechanisms and climate feedbacks associated with the Arctic and Antarctic climate, ocean and sea ice change, including the potential links of the pronounced Arctic amplification to weather and climate outside the Arctic, and teleconnections of high latitude climate with lower latitude climate. We also aim to link climate variability, predictions and projections to potential ecosystem and socio-economic impacts and encourage submissions on this topic.

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.

The polar climate system is strongly affected by interactions between the atmosphere and the cryosphere. Processes that exchange heat, moisture and momentum between land ice, sea ice and the atmosphere, such as katabatic winds, blowing snow, ice melt, polynya formation and sea ice transport, play an important role in local-to-global processes. Atmosphere-ice interactions are also triggered by synoptic weather phenomena such as cold air outbreaks, polar lows, atmospheric rivers, Foehn winds and heatwaves. However, our understanding of these processes is still incomplete. Despite being a crucial milestone for reaching accurate projections of future climate change in Polar Regions, deciphering the interplay between the atmosphere, land ice and sea ice on different spatial and temporal scales, remains a major challenge.

This session aims at showcasing recent research progress and augmenting existing knowledge in polar meteorology and climate and the atmosphere-land ice-sea ice coupling in both the Northern and Southern Hemispheres. It will provide a setting to foster discussion and help identify gaps, tools, and studies that can be designed to address these open questions. It is also the opportunity to convey newly acquired knowledge to the community.

We invite contributions on all observational and numerical modelling aspects of Arctic and Antarctic meteorology and climatology, that address atmospheric interactions with the cryosphere. This may include but is not limited to studies on past, present and future of:
- Atmospheric processes that influence sea-ice (snow on sea ice, sea ice melt, polynya formation and sea ice production and transport) and associated feedbacks,
- The variability of the polar large-scale atmospheric circulation (such as polar jets, the circumpolar trough and storm tracks) and impact on the cryosphere (sea ice and land ice),
- Atmosphere-ice interactions triggered by synoptic and meso-scale weather phenomena such as cold air outbreaks, katabatic winds, extratropical cyclones, polar cyclones, atmospheric rivers, Foehn winds and heatwaves,
- Role of clouds in polar climate and impact on the land ice and sea ice through interactions with radiation,
- Teleconnections and climate indices and their role in land ice/sea ice variability.

This session invites innovative Earth system and climate studies employing geodetic observations and methods. Modern geodetic observing systems have been instrumental in studying a wide range of changes in the Earth’s solid and fluid layers at various spatiotemporal scales. These changes are related to surface processes such as glacial isostatic adjustment, the terrestrial water cycle, ocean dynamics and ice-mass balance, which are primarily due to changes in the climate. To understand the Earth system response to natural climate variability and anthropogenic climate change, different time spans of observations need to be cross-compared and combined with several other datasets and model outputs. Geodetic observables are also often compared with geophysical models, which helps in explaining observations, evaluating simulations, and finally merging measurements and numerical models via data assimilation.



We look forward to contributions that:

1. Utilize geodetic data from diverse geodetic satellites including altimetry, gravimetry (CHAMP, GRACE, GOCE and GRACE-FO), navigation satellite systems (GNSS and DORIS) or remote sensing techniques that are based on both passive (i.e., optical and hyperspectral) and active (i.e., SAR) instruments.

2. Cover a wide variety of applications of geodetic measurements and their combination to observe and model Earth system signals in hydrological, ocean, atmospheric, climate and cryospheric sciences.

3. Show a new approach or method for separating and interpreting the variety of geophysical signals in our Earth system and combining various observations to improve spatiotemporal resolution of Earth observation products.

4. Work on simulations of future satellite mission (such as SWOT and GRACE-2) that may advance climate sciences.

5. Work towards any of the goals of the Inter-Commission Committee on "Geodesy for Climate Research" (ICCC) of the International Association of Geodesy (IAG).



We are committed to promoting gender balance and ECS in our session. With author consent, highlights from this session will be tweeted with a dedicated hashtag during the conference in order to increase the impact of the session.

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, exchange flows in semi-enclosed seas, eddies, sub-mesoscale processes, 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.

Coastal oceanographic processes present important differences with deep water oceanography, resulting in higher prediction errors, where bottom topography in shallow domains exerts a strong control on wave/current/turbulence fields. These fields are modified by many additional factors that include stratification, land boundary conditions and interactions with coastal infrastructure. The strong non-linear interactions (breaking waves, nearshore circulation), the choice of numerical strategy (nested meshes, finite-elements) or the modulations in restricted domains (suspended sediment clouds, vegetation filtering) may also play a critical role in the predictive quality. Coastal observations (in-situ and remote) are therefore necessary to drive and calibrate numerical models, where the advent of new satellite capabilities (e.g. Sentinel resolution and sensors) and new modelling advances (e.g. couplings or unstructured grids) together with enhanced Coastal Observatories, are leading to a qualitative advance of coastal oceanography. Coastal issues become more relevant in a framework of changing climate, since transitional areas are more strongly impacted by climate (e.g. changing domains due to sea-level rise) and therefore more in need of new approaches that include Natural based Solutions.
Because of these reasons, it is timely to discuss recent advances in: a) coastal coupled hydro-morpho-eco modelling at different scales; b) aggregation of in-situ/satellite/numerical data from different sources; c) knowledge-based coastal applications, including the assessment of Nature-based interventions; d) uncertainties in coastal decision-making, framed by an ethical approach and supported by quantitative information. Building upon these challenges, we invite presentations on coastal modelling and coupling, local assimilation, boundary effects or operational coastal predictions with/out interactions with Nature based or traditional interventions. Contributions exploring the potential and currently open issues of non-linear response functions, support from artificial intelligence and big data or uncertainty assessments for coastal applications are also welcome. These and related coastal topics should conform a fruitful session for discussing applications of coastal science to conventional and nature-based interventions under climate change. Please state if you would be interested in submitting your presentation to a peer reviewed special issue in Ocean Science.

Among other stressors, the Mediterranean and Black Seas have recently shown clear signs of climate change, including an increase in sea surface temperature in both basins, salinization of the intermediate and deep waters, a rise in sea level over the last century, and deoxygenation trends. These trends stress the vulnerability of these semi-enclosed and densely populated basins.

The urgent social and economic drivers require targeted improvements in weather, climate, water, oceans, and relevant environmental information and services. The risks associated with climate variability and extreme environmental events can lead to social and economic stresses that require new meteorological, hydrological, oceanographic, and climate services to ensure the safety and security of populations and the development of adaptive economic strategies.

This session is devoted to multidisciplinary scientific advances highlighting environmental trends at different spatial and temporal scales in the Mediterranean and Black Seas. We call for studies that address those threats in the Mediterranean and Black Seas including new approaches in physical and biogeochemical monitoring, ocean modeling, operational oceanography, and downstream product development.

The Paris Agreement on Climate sets the international objective to keep climate warming well below two degrees. This extraordinary challenge requires a dramatic improvement of current scientific capabilities to estimate the budgets and their trends of greenhouse gases (GHG) at regional scale, and how they link up to the global growth rates of the major GHGs (N2O, CH4 and CO2). This session aims to bring together studies to help understand and quantify regional budgets, trends and variability, and drivers of major GHG (N2O, CH4 and CO2) through the analyses of emissions inventories, field and remotely-sensed observations, terrestrial and ocean biogeochemical modeling, and atmospheric inverse modeling. We encourage contributions from the REgional Carbon Cycle Assessment and Processes (RECCAP2), a new global assessment of the Global Carbon Project, as well as studies combining different datasets and approaches at multi-scales from regional to global.

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

The radioactive materials are known as polluting materials that are hazardous for human society, but are also ideal markers in understanding dynamics and physical/chemical/biological reactions chains in the environment. Therefore, man-made radioactive contamination involves regional and global transport and local reactions of radioactive materials through atmosphere, soil and water system, ocean, and organic and ecosystem, and its relations with human and non-human biota. The topic also involves hazard prediction, risk assessment, nowcast, and countermeasures, , which is now urgent important for the nuclear power plants in Ukraine.

By combining long monitoring data (> halftime of Cesium 137 after the Chernobyl Accident in 1986, 12 years after the Fukushima Accident in 2011, and other events), we can improve our knowledgebase on the environmental behavior of radioactive materials and its environmental/biological impact. This should lead to improved monitoring systems in the future including emergency response systems, acute sampling/measurement methodology, and remediation schemes for any future nuclear accidents.

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

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

Tsunamis can produce catastrophic damage on vulnerable coastlines, essentially following major earthquakes, landslides, extreme volcanic activity or atmospheric disturbances.
After the disastrous tsunamis in 2004 and 2011, tsunami science has been continuously growing and expanding its scope to new fields of research in various domains, and also to regions where the tsunami hazard was previously underestimated.

The tsunami following the eruption of Hunga Tonga - Hunga Ha'apai in January 2022 provided a new and urging challenge, being an event with an extremely complicated source process and a consequently non-trivial global propagation, posing new questions in terms of modeling, hazard assessment and warning at different scales and evidencing the need for a closer cooperation among different research communities.

The spectrum of topics addressed by tsunami science nowadays ranges from the “classical” themes, such as analytical and numerical modelling of different generation mechanisms (ranging from large subduction earthquakes to local earthquakes generated in tectonically complex environments, from subaerial/submarine landslides to volcanic eruptions and atmospheric disturbances), propagation and run-up, hazard-vulnerability-risk assessment, especially with probabilistic approaches able to quantify uncertainties, early warning and monitoring, to more “applied” themes such as the societal and economic impact of moderate-to-large events on coastal local and nation-wide communities, as well as the present and future challenges connected to the global climate change.

This session welcomes multidisciplinary as well as focused contributions covering any of the aspects mentioned above, encompassing field data, geophysical models, regional and local hazard-vulnerability-risk studies, observation databases, numerical and experimental modeling, real time networks, operational tools and procedures towards a most efficient warning, with the general scope of improving our understanding of the tsunami phenomenon, per se and in the context of the global change, and our capacity to build safer and more resilient communities.

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.

Climate induced alterations to net primary production act alongside changes to biogeochemical cycling of oxygen and nutrients to affect marine ecosystem structure and function, as well as the ocean carbon cycle on decadal to centennial timescales. Climate change is driving alterations to these key components of ocean health, both via long term changes and the emergence of extremes. The 6th Climate Model Intercomparison Project provides new opportunities to analyze the long-term changes in biogeochemistry under different emissions scenarios, as well as to explore the emergence and potential impacts of extremes. Additionally, historical variability linked to climate oscillations such as ENSO and the Southern Annular Mode provide an opportunity to bring insights from observed changes and impacts. Moreover, isotope systems and proxies are often used in paleoclimate and paleoceanography across geologic timescales of climate change to interpret past environmental changes in Earth's history. Their interpretation relies heavily on these isotope systems' budget in the ocean.



This session invites submissions, from both observations and modelling efforts, that address the impact of climate change operating over multiple timescales on net primary production, biogeochemical cycling of nutrients and oxygen, and the ocean carbon cycle, including cascading effects for marine ecosystems to modulate biodiversity and ecosystem services.

Due to the growing pressures on marine resources and the ecosystem services demand, the interest of scientific and politic world is moving to ensure marine ecosystems conservation and environmental sustainable development providing policies to meet the UN 2030 Agenda Goal 14 in order to “Conserve and sustainably use the oceans, seas and marine resources for sustainable development”. To act against the decline of ocean health and to create a framework of stakeholders, the UN proposed the establishment of the “Decade of Ocean Science for Sustainable Development” able to bring regional knowledge and priorities together in an international action plan. Anthropogenic activities could have an impact on the marine environment and affect the ecosystem equilibrium. The marine environment is a dynamic, sensitive and fragile area in which it is advantageous to apply new methodologies and observing methods to increase the quantity and quality of the data. Since ocean dynamics affect the dispersion of pollutants such as chemicals, plastics, noise and invasive species, the ecosystems status should be analyzed through the study of abiotic variables distribution at a proper spatio-temporal scale. To analyze the ocean environmental quality, a large amount of data obtained by global observation systems (e.g. GOOS, EMODNET) is needed, which requires the development of cost-effective technologies for integrated observing systems and to support the study of, e.g., biological variables. The session focuses on marine ecosystems, technological developments for the study of abiotic and biotic factors, with a focus on anthropogenic impacts. 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 maintain, restore and 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; new technology development; advanced methods for collection, data processing, and information extraction; benthic and pelagic community dynamics; economic evaluation of natural capital.

Keeping global warming below 2°C will require drastic reductions in emissions together with large-scale removal of CO2 from the atmosphere that must be initiated within this decade to remove hundreds of gigatons of CO2 from the atmosphere over the coming decades. Ocean alkalinity enhancement (OAE) is a promising method to actively remove CO2 from the atmosphere whereby well-known chemical reactions, accelerate the ocean uptake of additional CO2 from the atmosphere, imitating geologic weathering processes that have sequestered trillions of tons of atmospheric CO2 in the ocean over millennia.
Compared to other carbon dioxide removal technologies, OAE has noticeable advantages since it is applicable to large regions of the coastal and open ocean and helps to mitigate ocean acidification. However, the effect of introducing gigatons of alkalinity, and potentially silicate, and dissolved metals on marine pelagic ecosystems remains unknown and the direct measurement of CO2 drawdown at scale from OAE is still unclear.
In this session, we welcome research ranging from field and laboratories experiments, theory, comparison with natural analogues and numerical modelling addressing the potential application of OAE and that could shed light on some still open questions: i) which are the ecological risks or co-benefit of OAE (ii) how can desired and undesired effects be identified, monitored, and mitigated; iii) under what conditions does OAE most efficiently sequester atmospheric CO2?

Over the past decade the increasing abundance of marine carbon measurements and the development of robust interpolation methods to fill gaps in space and time has led to an unprecedented increase in observation-based estimates of the air-sea CO2 exchange, as well as pH change in the open ocean and coastal seas and the storage rate of anthropogenic carbon in the subsurface ocean. Likewise, new model development has boosted our understanding of the driving processes and the future evolution of the global ocean carbon cycle. Altogether, the volume of data has exponentially increased, leading to new challenges and opportunities in further closing our outstanding knowledge gaps. In this session, we want to showcase the latest progress in our understanding of the marine carbon cycle from local to global scales. We invite observational studies, model studies and the combination of both e.g. through observational systems, simulation experiments, emergent constraints, machine learning, explainable AI techniques. The session will focus on the past, present and future ocean carbon cycle as well as its environmental impacts.

Coastal areas around the world are contaminated with dumped munitions. Most of these were dumped during and after the two world wars. Heavily populated coastal Europe is a particular hotspot, while also of great importance for shipping, fishing, offshore energy production and tourism. Apart from that, they are home to important ecosystems.
Off German coasts alone, it is estimated that more than 1.6 million tons of munitions have been corroding in the water in part for more than 100 years. These munitions are literally a ticking time bomb, as they pose a high risk of damage to the environment, both from possible detonations and from the leakage of toxic compounds. Experiments show that those munitions will corrode completely between 2020 and 2100. Most substances used in conventional munition are carcinogenic, mutagenic and toxic. In the last 10 years, there has been a growing awareness of the issue in Europe. Science is striving to qualify and quantify the exact hazard potential posed to humans and the environment by munitions submerged in the sea. This is the only way to establish action and prioritize recommendations for targeted clearance.
We are seeking contributions from the fields of biology, toxicology, and biochemistry that demonstrate studies of the effects of munitions components such as TNT, ADNT, DNB, TNB, and RDX on the marine environment. The overall goal is to expand the network within Europe and beyond to increase knowledge of the effects of these dormant hazards.

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 has depleted geological 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 on the magnitude and timing of P fluxes into aquatic ecosystems, influencing their trophic state. Burial in sediments returns P to the geological sink, eventually forming economically viable P deposits. Throughout the P cycle, redox conditions play a key role in transformations and mobility of P.

This interdisciplinary session invites contributions to the study of P from across the geosciences, and aims to foster 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 forests, soils and groundwater, through lakes, rivers and estuaries, to oceans, marine sediments and geological P deposits. We welcome studies of both past and present P cycling, with a focus on novel techniques and approaches.

The session will explore a wide range of key research (and policy) questions for blue carbon, carbon stored in marine and coastal ecosystems. This will support understanding of adaptation and mitigation processes within marine, small islands, and coastal ecosystems.
Since 196 Parties to the Paris Agreement committed to transforming their development trajectories towards sustainability and called for limiting global warming to well below 2°C – ideally 1.5°C – above pre-industrial levels, to meet these goals, global carbon dioxide emissions need to be reduced by 45% by 2030 and reach net zero by 2050. Global averages for carbon pools (soil organic carbon and living biomass) of focal coastal habitats. Carbon is stored in three coastal habitats, seagrass meadows, salt marshes, and mangroves, which are thought to be the largest repositories of carbon in marine and coastal ecosystems. Marine and coastal ecosystems, including small islands that are the interface between the terrestrial and marine ecosystems and are directly affected by climate change for relatively short periods, sequester and store more carbon per unit area than terrestrial forests and are now being recognized for their role in mitigating climate change.

IPCC has admitted Blue Carbon as carbon fluxes and storage in marine and coastal ecosystems. All biologically driven carbon fluxes and storage in marine and coastal ecosystems amenable to management can be considered blue carbon.
Therefore, we see blue carbon as an opportunity to contribute to global carbon reduction and climate change mitigation objectives.

This session invites researchers to work on:
1. Carbon uptake capabilities of marine, small islands, and coastal ecosystems
2. Functions of the marine, small islands, and coastal ecosystems
3. Comparison between coastal and terrestrial ecosystems by remote-sensed and in-situ observational, experimental, conceptual, and modeling approaches
4. Spatial and temporal changes of coastal ecosystems (marine, small islands, and coastal areas) in the past, present, and future

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 initiation, 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.

Tides play a pervasive role in the Earth system. They supply mechanical energy to fuel ocean turbulent dissipation and mixing, which in turn sustain the meridional overturning circulation, they modulate ice-shelf basal melt rates, cause coastal erosion, affect marine ecosystems and ocean biogeochemistry, and may raise or lower the sea-level baseline for storm surges. There are also tides in the atmosphere, which can impart terrestrial weather and climate variability well into the geospace. Looking down, precise measurements of solid Earth tides and the closely related ocean tidal loading are a unique means of probing Earth's interior and the frequency dependence of viscoelastic properties. Moreover, corrections for ocean tide signals underlie many Earth observation applications, including analyses of satellite altimetry and gravimetry data to determine sea level and ocean mass changes on local to global scales.

This session is open to research on any aspect of tides in the ocean, atmosphere, and solid Earth. We invite contributions on progress in numerical and empirical modelling of surface and internal tides in the ocean, the implications of internal tides for mixing and ocean circulation, modelling and observation of tidal variability, tidal analysis, atmosphere-ionosphere coupling through tides, and research into the role of tides in shaping Earth's ability to host life. Contributions may highlight tidal processes at any spatial and temporal scale on Earth and other planets.

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

Although it is a fundamental physical principle, energy conservation is generally not achieved in state-of-the-art ocean models. This can be mainly attributed to the model’s governing equations and their discretization, the coupling of different model components, or the parameterization of unresolved processes. This problem is not trivial, since from a theoretical and observational perspective the question of closing the energy budget poses several challenges: The energy is converted and propagated by a variety of processes such as eddies and waves acting on different spatial and temporal scales. In particular, instabilities and non-linear interactions among these processes transfer energy between the different dynamical regimes. For an appropriate description and understanding of our climate system, it is crucial to develop energetically consistent models to confidently predict climatic changes and quantify associated uncertainties.

This session invites contributions from theoreticians, modellers, and experimentalists with an aim to characterize oceanic energy pathways and their accurate representation in numerical models. This includes, but is not limited to, processes involving internal gravity waves,  (sub-)mesoscale turbulence, small-scale mixing, and ocean-atmosphere coupling. We welcome work that focuses on energy transfer processes and their quantification from in-situ measurements, (semi-)analytical approaches, and numerical models, as well as parameterizations of the key energy transfer processes, and spurious energy transfers associated with numerical discretizations. We also encourage cross-disciplinary contributions and presentations of novel approaches to data science that diagnose, quantify, and minimize energetic inconsistencies and related uncertainties.

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 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.

Despite their socio-economic and environmental impacts, extreme events in the marine environment are generally poorly understood, simulated or predicted. In particular, the dynamics of these events involve multiple temporal and spatial scales and can be driven by different mechanics and complex feedback involving the ocean and its interaction with the other spheres of the climate system.
In response to climate change, frequency and magnitude of these events could dramatically change with significant impacts on human life and properties as well as on marine ecosystems. Hence, advancing our understanding on the dynamics leading to extremes in marine environments is crucial to improving their predictability, which in turn will help to achieve environmental and social sustainability.
Starting with this rationale, the session will focus on marine extremes at multiple time and spatial scales. Studies discussing ocean dynamics and air-sea interactions that can influence the evolution of marine extremes are particularly welcome, as well as ones using techniques ranging from in-situ to remote sensing observations, from numerical models to innovative AI techniques (e.g., machine learning). This diversity of topics will make for a highly multidisciplinary session, open to multiple applications in the field of marine extremes.
Contributions related to the investigation of marine heatwaves, marine storminess, storm surge and sea level rise, dense water formation, deep ocean extreme events, etc. are other examples of potential topics.

Oceanographic monitoring and modeling are both widely used to study the pathways and fate of marine pollutants such as anthropogenic hydrocarbons, marine litter (including plastics, microplastics, and nanoplastics), POPs, HNS, radionuclides, pharmaceutics, etc. This session focuses on monitoring frameworks, computational tools, lab experiments and emerging technologies related to tracing pollutants and their impacts on local, regional, and global scales. Coupling with met-oceanographic and biogeochemical datasets provided, for example, by the Copernicus programme will also be discussed. State-of-the-art observational techniques and protocols, ensemble and multi-model methods, risk assessment algorithms and decision support systems are solicited topics. Integration of modelling, observing systems, and lab experiments for both data assimilation and model validation are also very welcome.

We welcome studies based on in situ and lab observational, and modeling work looking at physical and biogeochemical transformation of pollutants and impacts on ocean biogeochemistry and ecosystems such as fragmentation, biofouling, ingestion but also chemical impacts such as adsorption, transport and desorption of nutrients, heavy metals, and microbes. Discussions about newly discovered phenomena, as, for example, the mucilage outbreaks, a role of Extracellular Polymeric Substances (EPS), and other ecotoxicological issues are also encouraged.

Studies that link effects to broader ecosystem stressors like environmental degradation and climate change are particularly welcome. Monitoring and modeling the pollutants’ transport under the ice conditions are also appreciated, which is related to the increase in shipping traffic in the Arctic Ocean and melting the Polar ice as a consequence of the climate changes.

Key questions of the session are identified as follows: Which factors affect the dispersion of pollutants in the marine environment? What happens to the contaminants on the ocean’s surface, in the water column, and sediments? How do marine pollutants interact with marine habitats? How do they influence marine and maritime resources? How should Integrated Coastal Zone Management (ICZM) protocols be optimized to minimize negative impacts?

Influence of other environmental stressors, including artificial light, noise, and thermal pollution, on marine ecosystems and resilience to them, is also important subjects for discussion.

Over the last few years, there have been many evolutions in oceanographic models (e.g., NEMO), as well as in data assimilation used in marine environments.
NEMO (Nucleus for European Modelling of the Ocean) is a state-of-the-art modelling framework of the ocean that includes components for the ocean dynamics, sea-ice and biogeochemistry, along with a nesting package allowing for zooms, and versatile data assimilation interfaces (see https://www.nemo-ocean.eu/). The past few years have seen a great expansion in code functionality and capability. Additionally, the H2020 project IMMERSE and others have seen a multitude of new uses and exciting research coming out of the NEMO academic and operational oceanography community.
This session provides a platform for communication of NEMO and data assimilation developments in tandem with advertising the variety of applications (e.g., co-ocean dynamics at high latitudes; ocean biogeochemistry, climate projections: CMIP7 and beyond, coupling with data assimilation systems). This session aims to facilitate a lively exchange between developers and users, and together to identify gaps in our understanding.
Presentations of results based on new NEMO and data assimilation functionalities and new model configurations are welcome.

The Copernicus Marine Service (previously known as the Copernicus Marine Environment Monitoring Service, CMEMS) 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 (analysis and near-real time observations), the prediction of the ocean state a few days ahead (forecast), and the provision of consistent retrospective data records for recent decades (reanalyses and reprocessed observations). Copernicus Marine Service provides a sustainable response to private and public user needs, for academic, operational and private-sector activities and to support policies. The Copernicus Marine Service has started a new 7-yr phase covering 2021-2028.
The session focuses on the main Copernicus Marine Service activities on ocean modelling and coupling with other components of the climate system; data assimilation; processing of observations, impact and design of in-situ and satellite observing systems; verification, validation and uncertainty estimates of Copernicus Marine products; monitoring and long-term assessment of the ocean physical and biogeochemical states. Presentations dealing with the use and impact of Copernicus Marine products for downstream applications, including support to policies and directives, are also welcome.
Further, the session will encompass research activities that are required to maintain a state-of-the-art and user responsive Copernicus Marine Service and to prepare its long-term evolutions: extended range and ensemble ocean predictions, pan-European coastal zone monitoring, coupling with coastal systems and rivers, marine biology including higher trophic level modelling, Arctic ocean monitoring and forecasting and uptake of future Sentinel and other satellite missions, air/sea CO2 fluxes and carbon uptake, long-term regional ocean projections both for physics and biogeochemistry, digital oceans, big data and data science (AI, machine learning, etc).
Presentations are not limited to research teams directly involved in the Copernicus Marine Service and participation from external teams is strongly encouraged (e.g., from Horizon Europe projects relevant to Copernicus Marine and from downstream applications).

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.

This session covers predictions of climate from seasonal to decadal timescales and their applications. With a time horizon from a few months up a few decades, such predictions are of major importance to society, and improving them presents an interesting scientific challenge. This session embraces advances in our understanding of the origins of seasonal to decadal predictability, as well as in improving the forecast skill and making the most of this information by developing and evaluating new applications and climate services.

The session welcomes contributions from dynamical as well as statistical predictions (including machine learning methods) and their combination. This includes predictions of climate phenomena, including extremes, from global to regional scales, and from seasonal to multi-decadal timescales ("seamless predictions"). The session also covers physical processes relevant to long-term predictability sources (e.g. ocean, cryosphere, or land) and predictions of large-scale atmospheric circulation anomalies associated to teleconnections as well as observational and emergent constraints on climate variability and predictability. Also relevant is the time-dependence of the predictive skill and windows of opportunity. Analysis of predictions in a multi-model framework, and ensemble forecast initialization and generation, including innovative ensemble approaches to minimize initialization shocks, are another focus of the session. The session pays particular attention to innovative methods of quality assessment and verification of climate predictions, including extreme-weather frequencies, post-processing of climate hindcasts and forecasts, and quantification and interpretation of model uncertainty. We particularly invite contributions presenting the use of seasonal-to-decadal predictions for risk assessment, adaptation and further applications.

An increasing number of single model large ensemble simulations from Global Climate Models (GCM), Earth System Models (ESM), or Regional Climate Models (RCM) have been generated over recent years, to investigate internal variability and forced changes of the climate system — and to aid the interpretation of the observational record by providing a range of historical climate trajectories that could have been. The increased availability of large ensembles also enables new and inter-disciplinary applications beyond large-scale climate dynamics.

This session invites studies using large GCM, ESM, or RCM ensembles looking at the following topics: 1) Reinterpretation of the observed record in light of internal variability; 2) forced changes in internal variability; 3) development of new approaches to attribute and study observed events or trends; 4) impacts of natural climate variability; 5) assessment of extreme and compound event occurrence; 6) combining single model large ensembles with CMIP archives for robust decision making; 7) large ensembles as testbeds for method development.

We welcome research across all components of the Earth system. Examples include topics ranging from climate dynamics, hydrology and biogeochemistry to research on the role of internal variability in impact studies, focused for example on agriculture, air pollution or energy generation and consumption. We particularly invite studies that apply novel methods or cross-disciplinary approaches to leverage the potential of large ensembles.

A big challenge in Earth system science is providing reliable climate predictions on sub-seasonal, seasonal, decadal and longer timescales. Resulting data can potentially be translated into climate information for better assessment of global and regional climate-related risks. Latest developments and progress in climate forecasting on different timescales will be discussed and evaluated, including predictions for different time horizons from dynamical ensemble and statistical/empirical forecast systems, and the aspects required for their application: forecast quality assessment, multi-model combination, bias adjustment, downscaling, etc. Contributions on initialization methods that use observations from different Earth system components, on assessing and mitigating impacts of model errors on skill and on ensemble methods will be included, much as 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 development of early warning systems.
Another focus is on the use of operational climate predictions (C3S, NMME, S2S), results from CMIP5-CMIP6 decadal prediction experiments, and climate-prediction research and application projects. Since an important part of climate forecast is to apply appropriate downscaling methods -dynamic, statistical or a combination- to generate time series and fields with appropriate spatial or temporal resolution, this will be covered by the session, which aims to bring together scientists from all geoscientific disciplines working on the prediction and application problems. Following the new WCRP strategic plan for 2019-2029, prediction enhancements are also sought that embrace climate forecasting from an Earth system science perspective, including study of coupled processes between atmosphere, land, ocean and sea-ice components, and the impacts of coupling and feedbacks in physical, chemical, biological and human dimensions including migration. On migration, the focus is on migratory species or those that are forced to migrate due to a change in the frequency and severity of climatic disturbances or human intervention, i.e. land use land cover change. This part of the session is for researchers working on terrestrial, marine or freshwater species and studies covering all aspects of migration including trait and behavioral changes as a response to sudden or gradual environmental changes, at all temporal scales.

Modelling past climate states, and the transient evolution of Earth’s climate remains challenging. Time periods such as the Paleocene, Eocene, Pliocene, the Last Interglacial, the Last Glacial Maximum or the mid-Holocene span across a vast range of climate conditions. At times, these lie far outside the bounds of the historical period that most models are designed and tuned to reproduce. However, our ability to predict future climate conditions and potential pathways to them is dependent on our models' abilities to reproduce just such phenomena. Thus, our climatic and environmental history is ideally suited to thoroughly test and evaluate models against data, so they may be better able to simulate the present and make future climate projections.

We invite papers on palaeoclimate-specific model development, model simulations and model-data comparison studies. Simulations may be targeted to address specific questions or follow specified protocols (as in the Paleoclimate Modelling Intercomparison Project – PMIP or the Deep Time Model Intercomparison Project – DeepMIP). They may include anything between time-slice equilibrium experiments to long transient climate simulations (e.g. transient simulations covering the entire glacial cycle as per the goal of the PalMod project) with timescales of processes ranging from synoptic scales to glacial cycles and beyond. Comparisons may include past, historical as well as future simulations and focus on comparisons of mean states, gradients, circulation or modes of variability using reconstructions of temperature, precipitation, vegetation or tracer species (e.g. δ18O, δD or Pa/Th).

Evaluations of results from the latest phase of PMIP4-CMIP6 are particularly encouraged. However, we also solicit comparisons of different models (comprehensive GCMs, isotope-enabled models, EMICs and/or conceptual models) between different periods, or between models and data, including an analysis of the underlying mechanisms as well as contributions introducing novel model or experimental setups.

Inverse Problems are encountered in many fields of geosciences. One class of inverse problems, in the context of predictability, is assimilation of observations in dynamical models of the system under study. Furthermore, objective quantification of the uncertainty during data assimilation, prediction and validation is the object of growing concern and interest.
This session will be devoted to the presentation and discussion of methods for inverse problems, data assimilation and associated uncertainty quantification throughout the Earth System like in ocean and atmosphere dynamics, atmospheric chemistry, hydrology, climate science, solid earth geophysics and, more generally, in all fields of geosciences.
We encourage presentations on advanced methods, and related mathematical developments, suitable for situations in which local linear and Gaussian hypotheses are not valid and/or for situations in which significant model or observation errors are present. Specific problems arise in situations where coupling is present between different components of the Earth system, which gives rise to the so called coupled data assimilation.
Of interest are also contributions on weakly and strongly coupled data assimilation - methodology and applications, including Numerical Prediction, Environmental forecasts, Earth system monitoring, reanalysis, etc., as well as coupled covariances and the added value of observations at the interfaces of coupled models.
We also welcome contributions dealing with algorithmic aspects and numerical implementation of the solution of inverse problems and quantification of the associated uncertainty, as well as novel methodologies at the crossroad between data assimilation and purely data-driven, machine-learning-type algorithms.

The nonlinear nature of fluid flow gives rise to a wealth of interesting and beautiful phenomena. Many of these are of fundamental importance in the understanding of lakes, oceans and the atmosphere because of their role in such things as transport, the energy cascade and, ultimately, in mixing. This session is intended to bring together researchers interested in the fundamental nature of nonlinear processes in rivers, lakes, oceans and the atmosphere. Examples include, but are not limited to, nonlinear and solitary waves, wave-current and wave-wave interactions, flow instabilities and their nonlinear evolution, turbulence, frontogenesis, double diffusion and the nonlinear equation of state, convection, and river plumes. Presentations on theoretical, modelling, experimental or observational work are welcome.

Lagrangian tools allow to predict the dispersion of pollutants and track their sources, capture unresolved physics, and reveal transport pathways and barriers between flow regimes of fluid parcels that have different dynamical fates. As such, Lagrangian tools are used in a vast array of applications in geophysical fluid dynamics, from turbulent scales to planetary scales.

This session brings together scientists with experimental, numerical, and theoretical backgrounds.

Latest advancements will be presented on the following topics:
• Mesoscale to planetary-scale studies of transport and mixing (e.g. the AMOC, mixing in the surface ocean, identification of eddies and transport barriers);
• Tracking anthropogenic and natural influence (e.g. spread of microplastics, oil spills, volcanic ashes, and diseases);
• Micro-scale studies of turbulent flows (e.g. bubbles in the ocean surface layer, turbulence in the ocean and atmosphere);
• Tool development and numerical advances (e.g. use of machine learning, dynamic mode decomposition, trajectory rotation average, effects of model resolution);

Despite increasing public awareness about global plastic pollution and rising concerns about associated ecotoxicological risks, the annual amount of plastic waste released into natural environments continues to increase drastically. Proceeding pollution inevitably leads to spreading and accumulation of plastics through any sedimentary system, which is why plastics have been detected in almost every environment and natural habitat on Earth. To fully grasp the magnitude of the global plastic pollution problem and time scales associated with ecotoxicological consequences, we need to understand where plastic waste accumulates and how plastic items have been fragmented, depredated, and altered along their pathway. This includes a fundamental understanding of hydrodynamic transport processes including plastic-sediment interactions, as well as leaching processes of different types of plastics under various environmental conditions.

- Occurrence and spatial distribution of plastic waste in the environment
- Transport, deposition, and burial of plastics
- Fragmentation and degradation of plastics
- Leaching of chemical additives from plastics
- Toxicological studies on plastics or on chemical additives release from plastics
- Studies on the interaction between plastic and natural materials such as sediments
- Advanced analytical workflows suitable for the time-efficient and accurate analysis of small microplastics in sediments

The ocean represents a vast and largely untapped resource, which is being explored as a source of low carbon renewable energy. There is much research within the ocean science community into resource characterization and the interaction of energy conversion technologies with the ocean environment. We seek contributions spanning a broad range of topics relating to ocean renewable energy, including offshore wind, wave, ocean current and tidal resources over timescales ranging from semi-diurnal to decadal, and feedbacks between the available resource and energy extraction at local and regional scales. The session also seeks discussions on the application of ocean energy for ocean instrumentation/observation, powering off-grid buoys, unpiloted surface and underwater vehicles, and desalination. This session will gather and relate research methods and results from investigations into field techniques, and numerical/statistical modelling used to assess interactions of ocean renewable energy with ocean processes. The session will also include studies of physical impacts (e.g. impacts on sedimentary systems), and societal interactions (e.g. marine spatial planning). We also invite innovative research on ocean energy arrays/sites for co-located applications (e.g. offshore wind combined with aquaculture) that would benefit from combined infrastructure and reduced levelized costs.

The ocean floor hosts a tremendous variety of landforms that reflect the action of a range of tectonic, sedimentary, oceanographic and biological processes at multiple spatio-temporal scales. Many such processes present hazards to coastal populations and offshore installations, and their understanding constitutes a key objective of national and international research programmes and IODP expeditions. Recent advances in geophysical imaging, scientific ocean drilling, and seafloor instrumentation have increased the understanding of offshore geohazards; however, significant knowledge gaps remain in understanding the timing and interplay of geological processes at the origin of geohazards. High quality bathymetry, especially when combined with sub-seafloor and/or seabed measurements, provides an exciting opportunity to integrate the approaches of geomorphology and geophysics, as well as to extend quantitative geomorphology offshore and to integrate it into hazard analysis. 3D seismic reflection data has also given birth to the discipline of seismic geomorphology, which has provided a 4D perspective to continental margin evolution.

This interdisciplinary session aims to examine the causes and consequences of geomorphic processes shaping underwater landscapes, including submarine erosion and depositional processes, submarine landslides and canyons, sediment transfer and deformation, volcanic activity, fluid migration and escape, faulting and folding, and other processes acting at the seafloor. The general goal of the session is to bring together researchers who characterise the shape of past and present seafloor features, seek to understand the sub-surface and surface processes at work and their impacts, or use bathymetry and/or 3D seismic data as a model input, as well as to promote cooperation between different parties (academic, industrial, and governmental) involved in geohazard research and management. Contributions to this session can include work from any depth or physiographic region, e.g. oceanic plateaus, abyssal hills, mid-ocean ridges, accretionary wedges, and continental margins (from continental shelves to abyssal plains), as well as from lakes. Datasets of any scale, from satellite-predicted depth to ultra-high-resolution swath bathymetry, sub-surface imaging and sampling, are anticipated.

This session is co-organised by the IAG Submarine Geomorphology Working Group.

Fibre optic based techniques allow probing highly precise direct point and distributed sensing of the full ground motion wave-field including translation, rotation and strain, and environmental parameters such as temperature and even chemicals at a scale and to an extent previously unattainable with conventional geophysical methods. Considerable improvements in optical and atom interferometry enable new concepts for inertial rotation, translational displacement and acceleration sensing. Laser reflectometry using both fit-to-purpose and commercial fibre optic cables have successfully detected a variety of signals including microseism, local and teleseismic earthquakes, volcanic events, ocean dynamics, etc. Significant breakthrough in the use of fibre optic sensing techniques came from the new ability to interrogate telecommunication cables at high precision both on land and at sea, as well as in boreholes and at the surface. Applications of the resulting new type of data are manifold: they include seismic source and wave-field characterization with single point observations in harsh environments like active volcanoes, the ocean bottom, the correction of tilt effects, e.g. for high performance seismic isolation facilities, as well as seismic ambient noise interferometry and seismic building monitoring.

We welcome contributions on developments in instrumental and theoretical advances, applications and processing with fibre optic point and/or distributed multi-sensing techniques, light polarization and transmission analyses, using standard telecommunication and/or engineered fibre cables. We seek studies on theoretical, observation and advanced processing in fields, including seismology, volcanology, glaciology, geodesy, geophysics, natural hazards, oceanography, urban environment, geothermal applications, laboratory studies, large-scale field tests, planetary exploration, gravitational wave detection, fundamental physics. We encourage contributions on data analysis techniques, machine learning, data management, instrumental performance and comparison as well as new experimental, field, laboratory, modeling studies in fibre optic sensing studies.

We are happy to announce Prof. Martin Landrø, Prof. Kuo-Fong Ma and Dr. David Sollberger as invited speakers!

The state of the planet, especially climate and ocean (C&O), has become even more dire than just a year ago. Some quotes (mostly 2022) will illustrate this:
• The world is halfway through the time allocated for achieving the SDGs and the UN reports [that] countries have gone backwards on most of them. Bendell.
• Our world is suffering from the impact of unprecedented emergencies caused by the climate crisis, pollution, desertification and biodiversity loss. UN Secr-General, Guterres.
• Multiple climate tipping points could be triggered if global temperature rises beyond 1.5°C above pre-industrial levels. This will be disastrous for people across the world. futureearth.org, McKay, Rockström.

System-wide C&O education, with a good dose of geoethics, is a crucial key to reducing the impending tragedy. Thus C&O educators carry a great geoethical responsibility for the health of the Earth and the life that it carries, including humans. This also is a well-supported idea:
• Climate literacy is the key to a greener future. Conner.
• Understanding human behavior and the social drivers of climate change are essential for the public to fully appreciate the climate system. Shwom et al.
• Improved science and climate literacy are needed for planetary citizens to better understand the implications of global change. Harrington.
• Creating a climate-literate population is key to driving green jobs – and ambitious climate action. earthday.org
• It is about empowering people with tools, to better use that ocean knowledge to become more responsible and able to take decisions that involve ocean resources. Santoro, 2022.

The state of the climate and the related urgent need for climate education are captured in this quote:
• Since the IPCC (2018) 1.5°C Report, the global climate emergency has become widely acknowledged. With all adverse climate change indicators at record highs and global emissions still increasing, political will needs to be driven, hard and fast, making climate change literacy a survival imperative for civilization. Carter.

The above can be applied, mutatis mutandis, to related threats, such as biodiversity, pollution, food security and fossil-fuel-driven war. We welcome presentations from all cultures on a broad range of topics, from hands-on pedagogical methods and practices, through geo-communication, curriculum matters, outreach and research, to policy and its implementation.

Geoscience expertise is essential for the functioning of modern societies, to address many of the most urgent global problems, inform decision-making, and guide education at all levels, by equipping citizens to discuss, shape and implement solutions to local, regional and global social-environmental problems. In recent years, geoscientists have become more and more aware of ethical responsibilities to put their knowledge at the service of society, foster public trust in geosciences, and reflect on the environmental footprint of research practices. Geoethics aims to provide a common framework for orienting geoscientists’ concerns on delicate issues related geoscience-society interaction and to nourish a discussion on the fundamental principles and values which underpin appropriate behaviors and practices, wherever human activities interact with the Earth system.
The goal of the session is to foster the discussion on the following spectrum of topics:
- philosophical and historical aspects of geoscience, their contemporary relevance and role in informing methods for effective and ethical decision-making;
- geoscience professionalism and deontology, research integrity and issues related to harassment and discrimination, gender and disability in geosciences;
- ethical and social questions related to the management of land, air and water including environmental changes, pollution and their impacts;
- socio-environmentally sustainable supply of georesources (including energy, minerals and water), importance of effective regulation and policy-making, social acceptance, and understanding and promoting best practices;
- questioning professional practices in geosciences and their impact on the environment, and implementation of new practices to reduce it;
- resilience of society related to natural and anthropogenic hazards, risk management and mitigation strategies, including adaptation knowledge and solutions;
- ethical aspects of geoscience education and communication;
- culture and value of geodiversity, geoconservation, geoheritage, geoparks and geotourism;
- role of geosciences in achieving socio-economic development that respects cultures, traditions and local development paths, regardless of countries' wealth, and in promoting peace, responsible and sustainable development and intercultural exchange.
Session sponsored by International Association for Promoting Geoethics (www.geoethics.org).

Cloud computing has emerged as the dominant paradigm, supporting practically all industrial applications and a significant number of academic and research projects. Since its introduction in the early 2010s and its widespread adoption thereafter, migration to cloud computing has been a considerable task for many organisations and companies. Processing of big data close to their physical location is a perfect use case for cloud technologies and cloud storage infrastructure which offer all the necessary infrastructure and tools, especially if cloud infrastructure is offered together with HPC resources.
Pangeo (pangeo.io) is a global community of researchers and developers that tackle big geoscience data challenges in a collaborative manner using HPC and Cloud infrastructure.
This session's aim is threefold:
(1) Focuses on Cloud/Fog/Edge computing use cases and aims to identify the status and the steps towards a wider cloud computing adoption in Earth Observation and Earth Modeling.
(2) to motivate researchers that are using or developing in the Pangeo ecosystem to share their endeavors with a broader community that can benefit from these new tools.
(3) 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 encourage contributions describing all kinds of Cloud/Fog/Edge computing efforts in Earth Observation and Earth Modeling domains, such as:
- Cloud Applications, Infrastructure and Platforms (IaaS, PaaS SaaS and XaaS).
- Cloud federations and cross domain integration
- Service-Oriented Architecture in Cloud Computing
- Cloud Storage, File Systems, Big Data storage and Management.
- Networks within Cloud systems, the Storage Area, and to the outside
- Fog and Edge Computing
- Operational systems on the cloud.
- Data lakes and warehouses on the cloud.
- Cloud computing and HPC convergence in 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.

Awareness of the importance of the reproducibility of research results has increased considerably in recent years. Knowledge must be robust and reliable in order to serve as a foundation to build further progress on it. Reproducibility is a complex topic that spans technology, research communities, and research culture. In the narrow sense, reproducibility refers to the possibility of another researcher independently achieving the same result with the identical data and calculation methods. Put simply, one could say that research is either reproducible or not, but more practically there is a continuum of reproducibility where some factors weigh more heavily on influencing results. Replicability or replication, on the other hand, is a broader term and refers to one’s ability to replicate their own research. One problem, however, is that a large percentage of existing studies cannot be successfully reproduced or replicated. This endangers trust in science.

However, with the increasing complexity, volume and variety of Earth System Science (ESS) data - where data can be of multiple types like source code, entire workflows, observational or model output data - and the continuing push towards compliance with the FAIR data principles, achieving reproducibility is challenging. Dedicated solutions do exist only for a subset of implementation factors, but are mostly focused on single institutions or infrastructure providers. Current developments to establish the FDOs (FAIR Digital Objects) and corresponding frameworks go one step further to eventually enable a global interoperable data space to achieve scientific reproducibility. The adoption of Artificial Intelligence (AI), especially machine learning (ML), and other computational-intensive processes complicate this even further.

This session will explore current practices, methods and tools geared towards enabling reproducible results and workflows in ESS. We promote contributions from the areas of infrastructures, infrastructure requirements, workflow frameworks, software/tools, description of practices or other aspects (e.g. provenance tracking, quality information management, FDOs, AI/ML) that must be considered in order to achieve and enable reproducibility in Earth system sciences. These can be contributions that are generally valid and/or transferable or focus on certain areas of application. Finally, best practice examples (or as a counter-example bad practice) are also invited.

Taking inspiration from the Mathematics of Planet Earth 2013 initiative, this session aims at bringing together contributions from the growing interface between the Earth science, the mathematical, and the theoretical physical communities. Our goal is to stimulate the interaction among scientists of these and related disciplines interested in solving geophysical challenges. Considering the urgency of the ongoing climate crisis, such challenges refer, for example, to the theoretical understanding of the climate and its subsystems as a highly nonlinear, chaotic system, the improvement of the numerical modelling of the climate system, and the search for new data analysis methods.

Specific topics include: PDEs, numerical methods, extreme events, statistical mechanics, thermodynamics, dynamical systems theory, large deviation theory, response theory, tipping points, model reduction techniques, model uncertainty and ensemble design, stochastic processes, parametrizations, data assimilation and machine learning. We invite contributions both related to specific applications as well as more speculative and theoretical investigations. We particularly encourage early career researchers to present their interdisciplinary work in this session.

Solicited speakers: David Stainforth, Oana Lang

Networking is crucial for scientists of all career stages for collaborations as well as for their personal growth and career pathways. Your scientific network can support you when struggling with everyday academic life, help with making career choices and give feedback on job applications/proposals/papers. Further, having a scientific network can provide new perspectives and opportunities for your research while leading to interdisciplinary collaborations and new projects.
Building up an initial network can be challenging, especially outside of your research institution. As scientific conferences and social media platforms are evolving, the possibilities of academic networking are also changing. In this short course we will share tips and tricks on how to build, grow and maintain your scientific network. Additionally, panelists will talk about their own personal experiences. In the second part of the short course, we will do a networking exercise. This short course is relevant to scientists who are starting to build/grow their network or want to learn more about networking in today’s scientific settings.

Building a successful academic career is a challenge. Doing it while also building a family might push you to your limit. Many early and mid-career scientists are faced with the question of how to balance family and academic career. They are finding themselves left with a private problem, when it is actually a shared and societal issue, linking to other overarching themes of participation and diversity.
It is crucial to find support and confidence in going forward as an individual, and we as a community need to talk about parenting in academia to be able to demand and develop sustainable solutions that benefit many, instead of fighting private battles over and over again.
This short course aims to (1) provide some insight into how being a parent affects your every day academic life, (2) highlight the existing support measures for parents in academia in different countries, and (3) offer some experience-based strategies that are being shared by a panel of academic parents, (4) concluding with an open discussion, touching on the public discourses on equal parenting and life-work balance. This course targets scientists who think about having a family, as well as parents in academia keen to connect, and faculty staff with responsibilities towards parenting employees.

The work of scientists does not end with publishing their results in peer-reviewed journals and presenting them at specialized conferences. In fact, one could argue that the work of a scientist only starts at this point: outreach. What does science outreach mean? Very simply, it means to engage with the wider (non-scientific) public about science.
The way of doing outreach has radically changed in the last decades, and scientists can now take advantage of many channels and resources to tailor and deliver their message to the public: to name a few, scientists can do outreach through social media, by writing blogs, recording podcasts, organizing community events, and so on.
This short course aims to give practical examples of different outreach activities, providing tips and suggestions from personal and peers’ experiences to start and manage an outreach project. Specific attention will be paid to the current challenges of science communication, which will encompass the theme of credibility and reliability of the information, the role of communication in provoking a response to critical global issues, and how to tackle inequities and promote EDI in outreach, among others.
The last part of the course will be devoted to an open debate on specific hot topics regarding outreach. Have your say!

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
-Knowing your audience – harnessing the power of tailored openings/closings
-Captivating delivery – leveraging body language to your advantage
-Harnessing creativity - choosing the right medium
-Enunciating to engage – communicating across borders
-Effectively practising your pitch – making the best of your time
Early career and underrepresented scientists are particularly encouraged to participate as they can gain the most from the learning outcomes of this short course.

Visualisation of scientific data is an integral part of scientific understanding and communication. Scientists have to make decisions about the most effective way to communicate their results everyday. How do we best visualise the data to understand it ourselves? How do we best visualise our results to communicate with others? Common pitfalls can be overcrowding, overcomplicated plot types or inaccessible color schemes. Scientists may also get overwhelmed by the graphics requirements of different publishers, for presentations, posters etc. This short course is designed to help scientists improve their data visualization skills in a way that the research outputs would be more accessible within their own scientific community and reach a wider audience.
Topics discussed include:
- Choosing a plot type – keeping it simple
- Color schemes – which ones to use or not to use
- Creativity vs simplicity – finding the right balance
- Producing your figures and maps – software and tools
- Figure files – publication ready resolutions
This course is co-organized by the Young Hydrologic Society (YHS), enabling networking and skill enhancement of early career researchers worldwide. Our goal is to help you make your figures more accessible by a wider audience, informative and beautiful. If you feel your graphs could be improved, we welcome you to join this short course.

If you think your research is important and can make a difference in the world, but aren’t writing papers about making the world realize this, this is the session for you! To us, geoscience communication spans education, outreach, engagement and any studies into how any public (e.g. government, industry, an interest group) interacts with or consumes the geoscience that is your core business.

The session is a drop-in ‘clinic’ with the journal editors, so bring your ideas and questions!

The session will consist of roughly 10 mins of us talking, followed by small group or 1-to-1 discussion with a Geoscience Communication editor about your research idea – or how to integrate research into your geoscience communication activity (i.e. make it publishable).

It doesn’t matter if you know very little already. No question is too basic. It doesn’t matter how well developed (or not) your idea is. We can help you think about how to improve it, and to make it publishable – of course, we’d prefer Geoscience Communication. Alternatively, you could be an experienced geoscience communication practitioner who gets on with doing it, getting results, rather than writing a paper on it. In that case, we’d like to convince you that trying to publish is worth it!

The proposed short course is one that we have taught twice in-person and once virtually at the EGU over the past 4 years, and that has always been attended to full capacity and with very positive feedback, so that we propose to teach it again this year.

The climate system as a whole can be viewed as a highly complex thermal/heat engine, in which numerous processes continuously interact to transform heat into work and vice-versa. As any physical system, the climate system obeys the basic laws of thermodynamics, and we may therefore expect the tools of non-equilibrium thermodynamics to be particularly useful in describing and synthesising its properties. The main aim of this short course will be twofold. Part 1 will provide an advanced introduction to the fundamentals of equilibrium and non-equilibrium thermodynamics, irreversible processes and energetics of multicomponent stratified fluids. Part 2 will illustrate the usefulness of this viewpoint to summarize the main features of the climate system in terms of thermodynamic cycles, as well as a diagnostic tool to constrain the behavior of climate models. Although the aim is for this to be a self-contained module, some basic knowledge of the subject would be beneficial to the participants.
- The first part, chaired by Remi Tailleux, will provide an advanced introduction on the fundamentals of equilibrium and non-equilibrium thermodynamics, irreversible processes and energetics.
- The second part, chaired by Valerio Lembo and Gabriele Messori, will illustrate some applications of thermodynamics to the study of the climate system and its general circulation.

The climate is highly variable over wide ranges of scale in both space and time so that the amplitude of changes systematically depends on the scale of observations. As a consequence, climate variations recorded in time series or spatial distributions, which are produced through modelling or empirical analyses are inextricably linked to their space-time scales and is a significant part of the uncertainties in the proxy approaches. Rather than treating the variability as a limitation to our knowledge, as a distraction from mechanistic explanations and theories, in this course the variability is treated as an important, fundamental aspect of the climate dynamics that must be understood and modelled in its own right. Long considered as no more than an uninteresting spectral “background”, modern data shows that in fact it contains most of the variance.

We review techniques that make it possible to systematically analyse and model the variability of instrumental and proxy data, the inferred climate variables and the outputs of GCM’s. These analyses enable us to cover wide ranges of scale in both space and in time - and jointly in space-time - without trivializing the links between the measurements, proxies and the state variables (temperature, precipitation etc.). They promise to systematically allow us to compare model outputs with data, to understand the climate processes from small to large and from fast to slow. Specific tools that will be covered include spectral analysis, scaling fluctuation analysis, wavelets, fractals, multifractals, and stochastic modeling; we discuss corresponding software. We also include new developments in the Fractional Energy Balance Equation approach that combines energy and scale symmetries.

The main goal of this short course is to provide an introduction into the basic concepts of numerical modelling of solid Earth processes in the Earth’s crust and mantle in a non-technical manner. We discuss the building blocks of a numerical code and how to set up a model to study geodynamic problems. Emphasis is put on best practices and their implementations including code verification, model validation, internal consistency checks, and software and data management.

The short course introduces the following topics:
(1) The physical model, including the conservation and constitutive equations
(2) The numerical model, including numerical methods, discretisation, and kinematical descriptions
(3) Code verification, including benchmarking
(4) Model design, including modelling philosophies
(5) Model validation and subsequent analysis
(6) Communication of modelling results and effective software, data, and resource management

Armed with the knowledge of a typical numerical modelling workflow, participants will be better able to critically assess geodynamic numerical modelling papers and know how to start with numerical modelling.

This short course is aimed at everyone who is interested in, but not necessarily experienced with, geodynamic numerical models; in particular early career scientists (BSc, MSc, PhD students and postdocs) and people who are new to the field of geodynamic modelling.

Observations and measurements of geoscientific systems and their dynamical phenomena are genuinely obtained as time series or spatio-temporal data whose dynamics usually manifests a nonlinear multiscale (in terms of time and space) behavior. During the past decades, dynamical system, information theoretic, and stochastic approaches have rapidly developed and allow gaining novel insights on a great diversity of phenomena like weather and climate dynamics, turbulence in fluids and plasmas, or chaos in dynamical systems.

In this short course, we will provide an overview on a selection of contemporary topics related with complex systems based approaches and their utilization across the geosciences, exemplified by recent successful applications from various fields from paleoclimate over present-day atmospheric dynamics to Space Weather. The focus will be on tipping points and associated early warning indicators, the identification of causal relations among a multitude of observables, and how to combine both approaches in a multi-scale dynamical framework. The discussed data analysis tools are promising for investigating various aspects of both known and unknown physical processes.

Due to the continuous increase in geographical data set sizes and the number of computations that have to be performed in numerical modelling or data analyses, there is often a need to improve the performance and scalability of the software used. Developing such software can be challenging.

In this short course we will introduce the asynchronous many-tasks (AMT) approach, which can be used to develop software that performs and scales well over cores in a single computer as well as over nodes in a computer cluster. We will explain the general principles behind AMT, and show how the HPX C++ software library [1] can be used to develop an example algorithm, calculating hill shading from a digital elevation model, in parallel.

One advantage of using the HPX library is that it provides a single high-level API for performing parallel computations on both shared and distributed memory systems. This contrasts with a popular approach of using multiple APIs - and their associated programming models - for these, like OpenMP and MPI.

The HPX library is successfully being used in various HPC applications, one of which is the LUE numerical modelling framework [2, 3, 4]. With LUE model developers can implement their models using Python and execute them unchanged on their laptop or on a computer cluster.

The goal of this short course is to introduce the attendants to the principles behind AMT and the HPX library, and allow them to be able to decide whether the approach is applicable in their own use-cases. The short course is especially relevant for research software engineers, but we welcome everybody interested in the topic.

- [1] HPX website, https://hpx.stellar-group.org
- [2] LUE website, https://lue.computationalgeography.org
- [3] De Jong, K., Panja, D., Van Kreveld, M., Karssenberg, D. (2021), An environmental modelling framework based on asynchronous many-tasks: scalability and usability, Environmental Modelling & Software, doi: 10.1016/j.envsoft.2021.104998
- [4] De Jong, K., Panja, D., Karssenberg, D., Van Kreveld, M. (2022), Scalability and composability of flow accumulation algorithms based on asynchronous many-tasks, Computers & Geosciences, doi: 10.1016/j.cageo.2022.105083

Policies and decisions are often based on data products, such as dynamic maps and time series. The underlying data is ideally of high quality, but generating complete and accurate data is often a costly endeavour. Integrating sparse accurate sensors and low-cost instruments is a way to overcome this issue but it results in challenges related to interoperability. Moreover, the quality of combined data and how the resulting data product (e.g., a map showing an interpolation) is generated needs to be communicated transparently to users. An aggravating factor is that quality is not an absolute indicator but might depend on the use case and other factors (e.g, accuracy/precision of the sensors, deployment, data management). A computational notebook (e.g., R Markdown) can help to communicate how the quality of a dataset and the data product are calculated. For example, the notebook can show which observations are included/excluded in a map showing an interpolation.
In this short course, we will show how reproducible computational notebooks can help to communicate information on data quality effectively and transparently allowing users to understand, verify, and build on top of shareable workflows. To achieve that, we will demonstrate a use case from the EU-funded project MINKE on how the cooperation between the metrology and the oceanographic community can lead to an improved data reliability and use to address wicked problems related to “Life below water” (SDG 14). MINKE focuses on data quality and interoperability and aims to improve the use of existing research infrastructures and stimulate collaborations across research fields and citizen science.
In this hands-on course, we will apply tools to publish reproducible research, including R, R Markdown, Binder, and git. Furthermore, we will touch upon issues related to the computational environment and data management, thus covering Open Science principles (e.g., open code and data). This course is open to everyone interested in reproducibility of R-based workflows. We invite participants to follow the use case on their laptops and experiment with the computational workflow. Basic knowledge in R is needed, whereas knowledge in the other technologies is recommended but optional. The workflows will be reproducible in the browser. While the use case is from MINKE, the reproducibility concepts are applicable to other scenarios based on computational workflows.
Please register: https://forms.gle/34uD45xH3UKY6tiHA