Inter- and Transdisciplinary Sessions
Disciplinary sessions AS–GM
Disciplinary sessions GMPV–TS

Session programme


OS – Ocean Sciences

Programme group chair: Karen J. Heywood

OS4 – Global ocean processes and oceanographic techniques

Programme group scientific officer: Aida Alvera-Azcárate


This open session welcomes presentations in 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 AUVs. This includes all marine disciplines as well as interaction with the atmosphere and 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.

Convener: Callum RolloECSECS | Co-conveners: Isabelle GiddyECSECS, Matjaz Licer, Charles Troupin
| Attendance Tue, 05 May, 10:45–12:30 (CEST)

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

Co-organized by AS2
Convener: Alexander Babanin | Co-conveners: Francisco J. Ocampo-Torres, Miguel Onorato, Fangli Qiao
| Attendance Thu, 07 May, 14:00–18:00 (CEST)

In many respects internal gravity waves (IGWs) still pose major questions both to the atmospheric and ocean sciences, and to stellar physics. Important issues are IGW radiation from their various relevant sources, IGW reflection at boundaries, their propagation through and interaction with a larger-scale flow, wave-induced mean flow, wave-wave interactions in general, wave breaking and its implications for mixing, and the parameterization of these processes in models not explicitly resolving IGWs. Also the observational record, both on a global scale and with respect to local small-scale processes, is not yet sufficiently able to yield appropriate constraints. The session is intended to bring together experts from all fields of geophysical and astrophysical fluid dynamics working on related problems. Presentations on theoretical, modelling, experimental, and observational work with regard to all aspects of IGWs are most welcome. Besides, this year we welcome abstracts reporting results on the SouthTRAC campaign in the Southern Hemisphere, as well as any other major collaborative projects such as MS-GWaves.

Co-organized by AS1/NP7
Convener: Alvaro de la CamaraECSECS | Co-conveners: Ulrich Achatz, Chantal Staquet, Claudia StephanECSECS
| Attendance Fri, 08 May, 14:00–15:45 (CEST)

This session is open to science on the tides of the ocean, atmosphere and solid earth; on spatial scales from global to coastal, estuarine and river; and on all timescales. Tides can cause flooding, particularly in combination with storm surge, and tidal currents and water levels can be both a help and a hindrance to shipping and energy generation. There is a critical role for tides in ocean mixing and the cryosphere, and accurate tide models are required for the processing of remote sensing and satellite geodesy data.
We welcome presentations on progress in modelling of past, present, and future tides, assessment of the accuracy of tide models, novel methods for tide predictions, advances in instrumentation and data processing, new findings from the analysis of historical tide gauge data, and understanding of secular changes in tides due to sea-level change and other environmental forcing factors. We also invite submissions on tides of lakes and of other planets.
Déborah Idier of BGRM, the French Geological Survey, will give the invited presentation for this session, on the mechanisms of changes to tides on the European Shelf under sea-level rise.

Co-organized by G3/NH5
Convener: Joanne Williams | Co-conveners: Mattias Green, Michael Schindelegger, Sophie-Berenice WilmesECSECS
| Attendance Mon, 04 May, 14:00–15:45 (CEST)

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.

Solicited talk by Rosemary Morrow (LEGOS - OMP, France) & co-authors: Innovation in ocean satellite sensors in the next decade: an OceanObs19 perspective

Convener: Aida Alvera-Azcárate | Co-conveners: Craig Donlon, Christine Gommenginger, Guoqi Han, Tong Lee
| Attendance Mon, 04 May, 08:30–12:30 (CEST)

The Copernicus Marine Environment Monitoring Service (CMEMS) provides regular and systematic reference information on the physical and biogeochemical states (including sea-ice and sea state) of the global ocean and the European regional seas. This capacity encompasses the description of the current situation (analysis and near-real time observations), the prediction of the situation a few days ahead (forecast), and the provision of consistent retrospective data records for recent decades (re-analysis and reprocessed datasets). CMEMS provides a sustainable response to private and public user needs, for academic, operational, policy and blue growth activities related to all sectors of the blue economy: polar environment monitoring, marine conservation & policies, science & climate, natural resources & energy, water quality, coastal monitoring, society & education, marine food, marine navigation and safety & disaster.

The session will cover research activities that are required to maintain CMEMS systems at the state of the art and prepare their long-term evolution (e.g. physical and biogeochemical modeling; coupling with coastal systems and hydrology; coupling with sea-ice, atmosphere & waves; data assimilation both for physics and biogeochemistry, probabilistic forecasting; big data, cloud computing and processing, artificial intelligence etc.). Presentations on the use, impact and design of in-situ and satellite (e.g. Sentinel missions) observing systems relevant to CMEMS are also much welcome.

Presentations are not limited to research teams directly involved in CMEMS and participation from external teams is strongly encouraged (e.g. from H2020 projects relevant to CMEMS and downstream applications, from projects on seasonal to multidecadal regional projections for the coastal ocean and marine ecosystems, from projects dealing with the monitoring and forecasting of river discharge of freshwater and nutrients).

We also welcome scientific presentations (i) on the verification, validation and uncertainty estimates of CMEMS products, (ii) on the use of CMEMS products for downstream applications (including support to maritime regulations and directives) and (iii) on the monitoring and long-term assessment of the ocean physical and biogeochemical states.

Public information:
Programme (Public on EGU website)
4-5 minutes per display, except for solicited ones

8:30-8:32 Introducing the session

8:32-8:50 Solicited presentations
D2426 Pierre-Yves Le Traon | Copernicus Marine Service: achievements, future challenges and long-term evolution
D2433 Mike Bell | Challenges in ocean modelling and data assimilation for CMEMS

8:50-9:15 Blue Ocean
D2428 Eric De Boissésson | Monitoring marine heatwaves in CMEMS ocean analysis systems
D2440 Shihe Ren | Intercomparison and validation of detected SST fronts based on CMEMS high-resolution reanalysis data and satellite observations in the South China Sea
D2431 Hao Zuo | Benefits of dynamically modelled river discharge input for ocean and coupled system
D2432 Yicun Zhen | An adaptive optimal interpolation based on analog forecasting: application to SSH in the Gulf of Mexico
D2434 Markus Meier | Sources of uncertainty of Baltic Sea future projections
D2427 Stéphane Law Chune | WAVERYS : A CMEMS global wave reanalysis during the altimetry period

9:15-9:19 White Ocean
D2435 Guillaume Boutin (Timothy Williams) | Impact of wave-induced sea ice fragmentation on sea ice dynamics in the MIZ

9:19-9:35 Green Ocean
D2429 Elodie Gutknecht | Modelling the marine ecosystem of IBI European waters for CMEMS operational applications
D2436 Paolo Lazzari | Simulating bio-optical properties in the Mediterranean Sea
D2437 Anna Conchon | Gathering knowledge on mesopelagic ecosystems: insights from a parsimonious modelling approach
D2430 Marine Bretagnon | CMEMS Primary production from satellite remote sensing: spatial and temporal evolution and comparison with other products

9:35-9:45 Brown (coastal) ocean
D2441 Encarni Medina-Lopez | High-resolution sea surface salinity and temperature in coastal areas from Sentinel-2 and Copernicus Marine in situ data
D2442 Marc Mestres | CURAE – bridging the gap between regional CMEMS forecasts and coastal high-resolution applications

9:45-9:50 Validation
D2443 Marion Mittermaier | High-resolution model Verification Evaluation (HiVE). Part 2: Using object-based methods for the evaluation of algal blooms

9:50-10:05 Downstream applications
D2444 Miguel Inácio | The Copernicus Marine Environment Monitoring Service as a platform to map marine ecosystem services: a Lithuanian case study
D2438 Luis Rodriguez Galvez | Earth Observation services for Wild Fisheries, Oystergrounds Restoration and Bivalve Mariculture along European Coasts
D2439 Anne Vallette | Marine Litter Drift Monitoring (Forecast and Hindcast) in the Channel and the North Atlantic

10:05-10:15 Open Discussion


Chat Time 10:45–12:30

10:45 Introduction to the session

10:45-10:50 Ocean Reporting
D2445 Karina von Schuckmann (Pierre-Yves Le Traon) | Ocean reporting of the Copernicus Marine Environment Monitoring Service

10:50-11:00 In-situ observations
D2453 Mélanie Juza (Tanguy Szekely) | How CMEMS INSTAC contributes to the monitoring of the ocean?
D2461 Jérôme Gourrion | A novel statistical approach for Near-Real Time Quality Control of hydrographic observations

11:00-11:30 Blue Ocean
D2462 Stefania Angela Ciliberti | Progresses in the CMEMS BS-MFC for improving forecasting capabilities and monitoring the Black Sea region through high quality modelling systems
D2447 Guillaume Reffray | A new version of the IBI near real time system for November 2020: what will be changed?
D2450 Anna Chiara Goglio | A baroclinic tidal forecasting model for the Mediterranean Sea - First validation results
D2456 Romain Escudier | A high resolution reanalysis for the Mediterranean Sea
D2454 Alvise Benetazzo | Towards a unified framework for maximum wave computation from numerical models: outcomes from the LATEMAR project
D2455 Rianne Giesen (Ad Stoffelen) | Improved ocean wind forcing products

11:30-11:35 White Ocean
D2449 Timothy Williams | The neXtSIM-F sea ice forecasting platform

11:35-11:50 Green Ocean
D2452 Julien Lamouroux | Assessment of the CMEMS global biogeochemical forecasting operational system, with assimilation of Ocean Colour data
D2460 Yeray Santana-Falcón | Assimilation of chlorophyll data into a stochastic ensemble simulation for the North Atlantic ocean
D2448 Patrick Lehodey (Anna Conchon) | Zooplankton and Micronekton products from the CMEMS Catalogue for better monitoring of Marine Resources and Protected Species

11:50-11:55 Brown (coastal) Ocean
D2458 Francisco Campuzano | Framework for improving land boundary conditions in regional ocean products

11:55-12:05 Validation
D2446 Jan Maksymczuk | High-resolution model Verification Evaluation (HiVE). Part 1: Using neighbourhood techniques for the assessment of ocean model forecast skill
D2451 Malek Ghantous | Validation of the CMEMS-IBI wave model with data assimilation in a high resolution regional configuration

12:05-12:15 Downstream Applications
D2457 Nikolaos Kampanis (Katerina Spanoudaki) | The COASTAL CRETE downscaled forecasting system
D2459 Javier Bárcena (Javier García-Alba) | SOSeas: An assessment tool for predicting the dynamic risk of drowning on beaches

12:15-12:30 Open Discussion

12:30 Closing the session

Convener: Angelique Melet | Co-conveners: Stefano Ciavatta, Emanuela Clementi, Pierre De Mey
| Attendance Fri, 08 May, 08:30–12:30 (CEST)

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, the sea-ice and the biogeochemistry, so as a nesting package allowing to set up zooms and a versatile data assimilation interface (see https://www.nemo-ocean.eu/).
NEMO is used by a large community in Europe and world-wide (~200 projects, ~100 publications each year) covering a wide range of applications : oceanographic research, operational oceanography, seasonal forecast and climate projections.
NEMO is in particular used in 6 Earth System Models within CMIP6 and in Copernicus Marine Services (CMEMS) model-based products.

This session will provide a forum to properly address the new scientific advances in numerical modelling of the ocean and their implication for NEMO developments associated with:
• Ocean dynamics at large to coastal scales, up to 1km resolution ;
• Ocean biogeochemistry
• Sea-ice
• New numerical schemes associated to energy conservation constraints
• High performance computing challenges and techniques

The session will cover both research and operationnal activities contributing to new analysis, ideas and developments of ocean numerical models.
Presentations of results based on new NEMO functionalities and new NEMO model configurations are welcome.

Public information:
Registration for virtual session: https://framaforms.org/virtual-egu-os48-session-1587740583

Co-organized by CL5/ESSI1, co-sponsored by NEMO and IMMERSE
Convener: Claire Levy | Co-conveners: Mike Bell, Jerome Chanut, Doroteaciro IovinoECSECS, Julien Le Sommer
| Attendance Thu, 07 May, 14:00–15:45 (CEST)

Oceanographic monitoring and modeling are both widely used to study the pathways and fate of marine pollutants such as hydrocarbons, marine litter, POPs, HNS, radionuclides, etc. In this session, advanced sampling methods, models, operational applications and techniques related to tracing pollutants on local, regional and global scales, as well as the coupling with met-oceanographic transport fields from operational oceanography products such as Copernicus Marine Monitoring Environment Service will 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 and observing systems for both data assimilation and model validation are also very welcome.
Key questions of the session are identified as follows: Which factors affect the dispersion of the 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 impact on the coastal zone?
Impacts of pollutants, including light and noise pollution, on the marine ecosystems and resilience to pollution events are also important subjects for discussion: What is the behavior of oil, marine litter, heavy metals, and other pollutants in the water column, on various beach sediments, rocks and seabed? e.g., what is the biodegradation rate of oil droplets in the water column and what are the controlling factors? What is the rate of fragmentation, biofouling, and sedimentation of plastics? What are the mechanisms of beaching, seabed deposition, and resuspension of marine pollutants and what are the ways of entering the marine food chains (including human consumption)? What is the impact of light and noise pollution on the marine environment and habitats?

Co-organized by NH5
Convener: Giovanni Coppini | Co-conveners: Sebastien Legrand, Oleg Makarynskyy, Katerina Spanoudaki, George Zodiatis
| Attendance Mon, 04 May, 10:45–12:30 (CEST)

Plastic contamination has been reported in all realms of the environment from the tropics to the polar oceans. Our poor knowledge of plastics sources, pathways and hot spots of accumulation prevents an assessment of risks to ecosystems and human health and the development of appropriate mitigation strategies. In order to understand current distributions of plastics and the way they evolve in space and time, much better observations and common consistent measuring methods are required but simultaneously, observations must be systematically combined with computational models
The session aims to set up a forum for multi-disciplinary discussions to create a global picture of plastic contamination in the environment and to suggest approaches for future research, monitoring and mitigation of plastic pollutions impacts. The session will provide a platform for discussions to advise policy and industry on the best ways to assess potential harm to the environment and human health from this contaminant.
This session will draw together research on plastic contamination across all sizes of plastics from shelf seas to the deep ocean including ice covered seas. The forum will facilitate combining observations with state-of-the-art computational modelling to promote the fast advance of research and improve our understanding of how plastic pollution affects environments worldwide. We invite contributions on field and remote observations, laboratory experiments, novel modelling approaches, related scientific initiatives and projects. New ideas for citizen-science involvement and for mitigation strategies to reduce plastic contamination of the environment are especially welcome.

Co-organized by BG4
Convener: Stefanie RyndersECSECS | Co-conveners: Yevgeny Aksenov, H.G. Orr, Ilka Peeken, Anna Rubio
| Attendance Wed, 06 May, 08:30–10:15 (CEST)

The International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) senses the solid Earth, the oceans and the atmosphere with a global network of seismic, infrasound, and hydroacoustic sensors as well as detectors for atmospheric radioactivity. The primary purpose of the IMS data is for nuclear explosion monitoring regarding all aspects of detecting, locating and characterizing nuclear explosions and their radioactivity releases. On-site verification technologies apply similar methods on smaller scales as well as geophysical methods such as ground penetrating radar and geomagnetic surveying with the goal of identifying evidence for a nuclear explosion close to ground zero. Papers in this session address advances in the sensor technologies, new and historic data, data collection, data processing and analysis methods and algorithms, uncertainty analysis, machine learning and data mining, experiments and simulations including atmospheric transport modelling. This session also welcomes papers on applications of the IMS and OSI instrumentation data. This covers the use of IMS data for disaster risk reduction such as tsunami early warning, earthquake hazard assessment, volcano ash plume warning, radiological emergencies and climate change related monitoring. The scientific applications of IMS data establish another large range of topics, including acoustic wave propagation in the Earth crust, stratospheric wind fields and gravity waves, global atmospheric circulation patterns, deep ocean temperature profiles and whale migration. The use of IMS data for such purposes returns a benefit with regard to calibration, data analysis methods and performance of the primary mission of monitoring for nuclear explosions.

Co-organized by AS4/NH10/OS4
Convener: Martin Kalinowski | Co-conveners: Lars Ceranna, Yan Jia, Peter Nielsen, Ole Ross
| Attendance Mon, 04 May, 08:30–12:30 (CEST)

Satellite altimetry provides the possibility to observe key parts of the hydrosphere, namely the ocean, ice, and continental surface water from space. Since the launch of Topex/Poseidon in 1992 the applications of altimetry have expanded from the open oceans to coastal zones, inland water, land and sea ice. Today, seven missions are in orbit, providing dense and near-global observations of surface elevation and several other parameters. Satellite altimetry has become an integral part of the global observation of the Earth‘s system and changes therein.

In recent years, new satellite altimetry missions have been launched carrying new instruments and operating in new orbits; the CryoSat-2/Sentinel-3 missions equipped with a Delay/Doppler altimeter, the Saral AltiKa mission carrying the first Ka band altimeter, and the recently launched photon counting laser altimeter on-board NASAs ICESat-2.

Fully exploiting this unprecedented availability of observables will enable new applications and results but also require novel and adapted methods of data analysis.
Across the different applications for satellite altimetry, the data analysis and underlying methods are similar and a knowledge exchange between the disciplines will be fruitful.
In this multidisciplinary altimetry session, we therefore invite contributions which discuss new methodology and applications for satellite altimetry in the fields of geodesy, hydrology, cryosphere, oceanography, and climatology.
Topics of such studies could for example be (but not limited to): creation of robust and consistent time series across sensors, validation experiments, combination of radar and laser altimetry e. g. for remote sensing of snow, classification of waveforms, application of data in a geodetic orbit, retracking, or combination with other remote sensing data sets.

Co-organized by CR2/HS6/OS4
Convener: Eva BoergensECSECS | Co-conveners: Stefan Hendricks, Karina Nielsen, Louise Sandberg Sørensen, Bernd UebbingECSECS
| Attendance Wed, 06 May, 10:45–12:30 (CEST)

The session presents the state of art information systems in oceanography (metadata, vocabularies, ISO and OGC applications, data models), interoperability (Virtual Research Infrastructures, Interoperability forms, Web services, Quality of Services, Open standards), data circulation and services (quality assurance / quality control, preservation, network services) and Education in ocean science (Education and Research, Internet tools for education).
The 2020 session should provide new ideas on the interoperability issues deriving from different sources of data.
ISO standards introduce the necessary elements in the abstract process aiming to assess ‘how’ and ‘how much’ data meets applicable regulatory requirements and aims to enhance user needs. Data management infrastructures should include an evaluation of data by assuring relevance, reliability and fitness-for-purposes / fitness-for-use, adequacy, comparability and compatibility. Presenters are strongly encouraged to demonstrate how their efforts will benefit their user communities, facilitate collaborative knowledge building, decision making and knowledge management in general, intended as a range of strategies and practices to identify, create, represent and distribute data, products and information.

Co-organized by OS4
Convener: Antonio Novellino | Co-conveners: Luca BonofiglioECSECS, Cristian MunozECSECS, Simona Simoncelli
| Attendance Mon, 04 May, 10:45–12:30 (CEST)

Environmental systems often span spatial and temporal scales covering different orders of magnitude. The session is oriented in collecting studies relevant to understand multiscale aspects of these systems and in proposing adequate multi-platform and inter-disciplinary surveillance networks monitoring tools systems. It is especially aimed to emphasize the interaction between environmental processes occurring at different scales. In particular, a special attention is devoted to the studies focused on the development of new techniques and integrated instrumentation for multiscale monitoring high natural risk areas, such as: volcanic, seismic, energy exploitation, slope instability, floods, coastal instability, climate changes and other environmental context.
We expect contributions derived from several disciplines, such as applied geophysics, geology, seismology, geodesy, geochemistry, remote and proximal sensing, volcanology, geotechnical, soil science, marine geology, oceanography, climatology and meteorology. In this context, the contributions in analytical and numerical modeling of geological and environmental processes are also expected.
Finally, we stress that the inter-disciplinary studies that highlight the multiscale properties of natural processes analyzed and monitored by using several methodologies are welcome.

Co-organized by AS4/CL2/GM2/GMPV9/NH8/NP3/OS4/SM5/SSS10
Convener: Pietro Tizzani | Co-conveners: Antonello Bonfante, Francesca Bianco, Raffaele Castaldo, Nemesio M. Pérez, Annalisa Cappello
| Attendance Fri, 08 May, 08:30–12:30 (CEST)

This session invites innovative Earth system and climate studies based on geodetic measuring techniques. Modern geodetic observing systems document a wide range of changes in the Earth’s solid and fluid layers at very diverging spatial and temporal scales related to processes as, e.g., glacial isostatic adjustment, the terrestrial water cycle, ocean dynamics and ice-mass balance. Different time spans of observations need to be cross-compared and combined to resolve a wide spectrum of climate-related signals. Geodetic observables are also often compared with geophysical models, which helps to explain observations, evaluate simulations, and finally merge measurements and numerical models via data assimilation.
We appreciate contributions utilizing 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. We welcome studies that 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. Any new approaches helping to separate and interpret the variety of geophysical signals are equally appreciated. Contributions working towards the newly established Inter-Commission Committee on "Geodesy for Climate Research" (ICCC) of the International Association of Geodesy (IAG) would be particularly interesting for this 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.

Co-organized by AS5/CL2/ESSI1/OS4
Convener: Anna KlosECSECS | Co-conveners: Carmen Boening, Henryk Dobslaw, Roelof RietbroekECSECS, Bert Wouters
| Attendance Wed, 06 May, 16:15–18:00 (CEST)

This session aims at fostering discussions on the physical processes at work at the air-sea interface, including their observation and their representation in coupled numerical models. Examples of such processes are solar radiation-induced diurnal warming and rain-induced cool and fresh lenses, as well as gustiness associated with atmospheric boundary layer thermals or moist convection and cold pools induced by rain evaporation. Air-sea interaction related to surface temperature and salinity fronts, as well as oceanic meso- and sub-mesoscale dynamics, are also of great interest.

This session is thus intended for (i) contributions presenting observational or theoretical aspects of the processes described above and their impact on energy, water, momentum, gas and aerosols exchanges at the interface; and (ii) contributions focusing on the mathematical and algorithmic methods used to represent these processes in coupled ocean-atmosphere models.

This session seeks observational studies based on recent field campaigns or satellite remote sensing. This session also aims to gather studies using numerical models of any level of complexity (from highly idealized to realistic) and any resolution from Large Eddy Simulation (LES) to global circulation models. Studies describing the impact of the air-sea interaction physical processes on the mean global or regional climates and variability representation are also welcome.

Co-organized by OS4
Convener: Hugo Bellenger | Co-conveners: Kyla Drushka, Audrey Hasson, Brian Ward
| Attendance Fri, 08 May, 16:15–18:00 (CEST)

Data assimilation systems and numerical weather and climate models are essential to understand the current and past state of the Earth System, and to predict it's future. This session will summarize the latest progress in the development of such models including the assimilation of space-borne and conventional observations, developments for the numerical formulation of the models regarding both the fluid dynamic solver and physical parametrisation schemes, and developments towards weather and climate simulations at higher resolution on modern supercomputers.

Public information:
We will divide the session chats into smaller groups of 4 abstracts based on the order of abstracts in the session programme. Each group will have ~15 minutes. Each mini-session will be organized as follows:

- All authors post a few sentences to present their work.
- Everyone attending the mini-session can post questions or comments to the authors.
- All post related to one particular abstract should begin with the name of the first author. E.g. @David: What is the y-axis of Figure 2?

Co-organized by CL2/OS4
Convener: Peter Düben | Co-conveners: Werner Bauer, Daniel Klocke, Isaac Moradi, Jemma Shipton
| Attendance Thu, 07 May, 08:30–12:30 (CEST)

One of the big challenges in Earth system science consists in providing reliable climate predictions on sub-seasonal, seasonal, decadal and longer timescales. The resulting data have the potential to be translated into climate information leading to a better assessment of multi-scale global and regional climate-related risks.
The latest developments and progress in climate forecasting on subseasonal-to-decadal timescales will be discussed and evaluated in this session. This will include presentations and discussions of predictions for a time horizon of up to ten years from dynamical ensemble and statistical/empirical forecast systems, as well as the aspects required for their application: forecast quality assessment, multi-model combination, bias adjustment, downscaling, etc.
Following the new WCPR strategic plan for 2019-2029, prediction enhancements are solicited from contributions embracing climate forecasting from an Earth system science perspective. This includes the study of coupled processes, impacts of coupling and feedbacks, and analysis/verification of the coupled atmosphere-ocean, atmosphere-land, atmosphere-hydrology, atmosphere-chemistry & aerosols, atmosphere-ice, ocean-hydrology, ocean-ice, ocean-chemistry and climate-biosphere (including human component). Contributions are also sought on initialization methods that optimally use observations from different Earth system components, on assessing and mitigating the impacts of model errors on skill, and on ensemble methods.
We also encourage contributions on the use of climate predictions for climate impact assessment, demonstrations of end-user value for climate risk applications and climate-change adaptation and the development of early warning systems.

A special focus will be put on the use of operational climate predictions (C3S, NMME, S2S), results from the CMIP5-CMIP6 decadal prediction experiments, and climate-prediction research and application projects (e.g. EUCP, APPLICATE, PREFACE, MIKLIP, MEDSCOPE, SECLI-FIRM, S2S4E).
An increasingly important aspect for climate forecast's applications is the use of most appropriate downscaling methods, based on dynamical or statistical approaches or their combination, that are needed to generate time series and fields with an appropriate spatial or temporal resolution. This is extensively considered in the session, which therefore brings together scientists from all geoscientific disciplines working on the prediction and application problems.

Co-organized by NP5/OS4
Convener: Andrea Alessandri | Co-conveners: Louis-Philippe Caron, Marlis HoferECSECS, June-Yi Lee, Xiaosong Yang
| Attendance Tue, 05 May, 14:00–15:45 (CEST)

Lagrangian trajectories are currently used for vast range of purposes in ocean and atmosphere science. Examples include studying the connectivity of ocean basins, forecasting the spreading of ash clouds, mapping global ocean diffusivities, observing the deep ocean, or tracing plastics and other forms of pollutants in the ocean, etc. There is thus a need for numerical models capable of simulating Lagrangian particles in the ocean and atmosphere as well as accurate methods for analysing the data from surface drifters, floats, and simulated particles.

This session aims at bringing together scientists working on all sorts of Lagrangian methods, e.g. observed or simulated particles in the atmosphere and ocean, and a variety of use cases e.g. studying oceanic mixing/diffusivity, tracing pollution in the atmosphere or ocean, iceberg tracking etc. We welcome presentations on e.g.:

- Connectivity and pathways of air- or water-masses in the atmosphere and ocean
- Development of Lagrangian particle-tracking algorithms and algorithms to model particles with active behaviours, e.g. icebergs, fish, ash clouds, plastics etc.
- Methods and new tools to analyse observed or simulated Lagrangian particles, e.g. diffusivity, spreading rates, etc.
- New instrumentations and developments of balloons, surface drifters and floats.

Co-organized by AS5/OS4
Convener: Joakim KjellssonECSECS | Co-conveners: Kristofer Döös, Bror Jonsson
| Attendance Mon, 04 May, 08:30–10:15 (CEST)

The multitude of processes of various scales occurring simultaneously under strong winds in the air and sea boundary layers presents a true challenge for nonlinear science. We want to understand the physics of these processes, their specific role, their interactions and how they can be probed remotely, how these processes differ from their counterparts under moderate/weak winds. We welcome theoretical, experimental and numerical works on all aspects of processes in turbulent boundary layers above and below the ocean surface. Although we are particularly interested in the processes and phenomena occurring under strong wind conditions, the works concerned with similar processes under weaker winds which might provide an insight for rough seas are also welcomed. We are also very interested in works on remote sensing of these processes.
The areas of interest include the processes at and in the vicinity of the interface (nonlinear dynamics of surface water, wave-turbulence interactions, wave breaking, generation and dynamics of spray and air bubbles, thermodynamics of the processes in the boundary layers, heat and gas exchange), all the processes above and below the aIr/water interface, as long as they are relevant for strong wind conditions (such as, e.g. inertial waves generated by changing winds). Relevant nonlinear biological phenomena are also welcomed.
The main aims of the session is to initiate discussion of the multitude of processes active under strong winds across the narrow specializations as a step towards creating an integrated picture. Theoretical, numerical, experimental and observational works are welcomed.

Geophysical Fluid Dynamics (GFD) is a truly interdisciplinary field, including different topics dealing with rotating stratified fluids. It emerges in the late 50s, when scientists from meteorology, oceanography, astrophysics, geological fluid dynamics, and applied mathematics began to mathematically model complex flows and thereby unify these fields. Since then many new aspects were added and deeper insight into many problems has been achieved. New mathematical and statistical tools were developed, standard techniques were refined, classical problems were varied. In this session we primarily focus on contributions from dynamic meteorology and physical oceanography that model flows by mathematical analysis. However, it is also a forum for experimental GFD and for astrophysical and geological aspects of GFD as well.

Co-organized by AS2/NH1/OS4
Convener: Yuliya Troitskaya | Co-conveners: Uwe Harlander, Vladimir Kudryavtsev, Victor Shrira, Wu-ting Tsai, Claudia Cherubini, Michael Kurgansky, Andreas Will
| Attendance Fri, 08 May, 10:45–12:30 (CEST), Attendance Fri, 08 May, 14:00–15:45 (CEST)

Recent years have seen a substantial progress in the understanding of the nonlinear and stochastic processes responsible for important dynamical aspects of the complex Earth system. The Earth system is a complex system with a multitude of spatial and temporal scales which interact nonlinearly with each other. For understanding this complex system new methods from dynamical systems, complex systems theory, complex network theory, statistics and climate and Earth sciences are needed.

In this context the session is open to contributions on all aspects of the nonlinear and stochastic dynamics of the Earth system, including the atmosphere, the ocean and the climate system. Communications based on theoretical and modeling studies, as well as on experimental investigations are welcome. Studies that span the range of model hierarchy from idealized models to complex Earth System Models (ESM), data driven models, use observational data and also theoretical studies are particularly encouraged.

Invited Speaker: Anna von der Heydt (Utrecht University)

Co-organized by AS4/CL4/NH1/OS4
Convener: Christian Franzke | Co-conveners: Hannah Christensen, Balasubramanya Nadiga, Paul Williams, Naiming Yuan, François G. Schmitt, Guillaume Charria, Véronique Garçon
| Attendance Wed, 06 May, 14:00–15:45 (CEST)

The ocean floor hosts a tremendous variety of forms that reflect the action of a range of tectonic, sedimentary, oceanographic and biological processes at multiple spatio-temporal scales. Being able to map the form and shape of the seabed and to understand the processes that shape it is a major prerequisite to ocean and coastal management, nature conservation and hazard assessment as well as a key objective of national and international research programmes and IODP expeditions.

High quality seafloor maps are integral to submarine geomorphic investigations. Acoustic remote-sensing technologies (singlebeam, multibeam, sidescan, interferometric and synthetic-aperture sonars), deployed on various platforms, are fundamental to seafloor mapping. In relatively shallow and transparent waters, optical methods such as aircraft and satellite-based remote sensing and LIDAR are being employed with increasing success. Seafloor maps, especially when combined with sub-seafloor and/or seabed measurements, provide an exciting opportunity to integrate the approaches of geomorphology and geophysics, and to extend quantitative geomorphology offshore. 3D seismic reflection data has also given birth to the discipline of seismic geomorphology, which has provided a 4D perspective to continental margin evolution. Innovative processing and classification software, image analysis, machine and deep-learning applications are advancing developments in seabed-recognition techniques.

The aim of this interdisciplinary session is two-fold: (i) to highlight recent advances in seabed mapping and classification, and (ii) to improve the understanding of the causes and consequences of geomorphic processes shaping underwater landscapes, including submarine erosion and depositional processes, submarine landslides, sediment transfer and deformation, volcanic activity, fluid migration and escape, faulting and folding, among others. Contributions to this session can include work from any physiographic region, ranging from shallow coastal settings to abyssal plains and deep-sea trenches. Datasets of any scale, from satellite-predicted depth to ultra-high resolution swath bathymetry, sub-surface imaging and sampling, are anticipated.

Co-organized by OS4/SSP3, co-sponsored by IAG
Convener: Aaron Micallef | Co-conveners: Markus Diesing, H. Christian Hass (deceased), Sebastian Krastel, Alessandra Savini, Maria Judge, Kim Picard, Anne-Cathrin WölflECSECS
| Attendance Wed, 06 May, 14:00–18:00 (CEST)

This session welcomes contributions presenting advances in, and approaches to, studying, modelling, monitoring, and forecasting of internal waves in stratified estuaries, lakes and the coastal oсean.

Internal solitary waves (ISWs) and large-amplitude internal soliton packets are a commonly observed event in oceans and lakes. In the oceans ISWs are mainly generated by the interaction of the barotropic tides with the bottom topography. Large amplitude solitary waves are energetic events that generate strong currents. They can also trap fluid with larvae and sediments in the cores of waves and transport it a considerable distance. ISWs can cause hazards to marine engineering and submarine navigation, and significantly impact on marine ecosystems and particle transport in the bottom layer of the ocean and stratified lakes. Contributions studying flows due to internal waves, their origin, propagation and influence on the surrounding environment are of great importance.
The scope of the session involves all aspects of ISWs generation, propagation, transformation and the interaction of internal waves with bottom topography and shelf zones, as well as an evaluation of the role of internal waves in sediment resuspension and transport. Breaking of internal-waves also drives turbulent mixing in the ocean interior that is important for climate ocean models. Discussion of parameterizations for internal-wave driven turbulent mixing in global ocean models is also invited.

Co-organized by NP7/OS4
Convener: Kateryna Terletska | Co-conveners: Marek Stastna, Tatiana Talipova, Zhenhua Xu
| Attendance Thu, 07 May, 10:45–12:30 (CEST)

Earth Systems Models aim at describing the full water- and energy cycles, i.e. from the deep ocean or groundwater across the sea or land surface to the top of the atmosphere. The objective of the session is to create a valuable opportunity for interdisciplinary exchange of ideas and experiences among members of the Earth System modeling community and especially atmospheric-hydrological modelers.
Contributions are invited dealing with approaches how to capture the complex fluxes and interactions between surface water, groundwater, land surface processes, oceans and regional climate. This includes the development and application of one-way or fully-coupled hydrometeorological prediction systems for e.g. floods, droughts and water resources at various scales. We are interested in model systems that make use of innovative upscaling and downscaling schemes for predictions across various spatial- and temporal scales. Contributions on novel one-way and fully-coupled modeling systems and combined dynamical-statistical approaches are encouraged. A particular focus of the session is on weakly and strongly coupled data assimilation across the different compartments of the Earth system for the improved prediction of states and fluxes of water and energy. Merging of different observation types and observations at different length scales is addressed as well as different data assimilation approaches for the atmosphere-land system, the land surface-subsurface system and the atmosphere-ocean system. The value of different measurement types for the predictions of states and fluxes, and the additional value of measurements to update states across compartments is of high interest to the session. We also encourage contributions on use of field experiments and testbeds equipped with complex sensors and measurement systems allowing compartment-crossing and multi-variable validation of Earth System Models.

Co-organized by AS2/BG2/NH1/NP5/OS4
Convener: Harald Kunstmann | Co-conveners: Harrie-Jan Hendricks Franssen, Alfonso Senatore, Gabriëlle De Lannoy, Martin Drews, Lars Nerger, Stefan Kollet, Insa Neuweiler
| Attendance Tue, 05 May, 10:45–12:30 (CEST)