At the Ocean Sciences division meeting we will present awards, review our activities, share information with the ocean science community, and discuss how EGU can better meet your needs. Everyone is very welcome, from all career stages.

For the open session, we welcome contributions on all aspects of ocean circulation from observations, models and theory, from regional to global scales, from air-sea exchanges to abyssal mixing. This year our session will include the Fridtjof Nansen medal award lecture, by Anne-Marie Treguier. We particularly encourage studies on the interannual to decadal variability and the internal and externally forced physical processes in the ocean. Because accurate estimation of energy and mass fluxes is critical for the closure of the ocean energy budget and the ocean's impact on the atmosphere, this session also welcomes works dealing with processes at the ocean's boundaries. This includes studies focusing on the fundamentals of air-sea flux physics, on the ocean's interaction with the cryosphere, as well as on the physical processes occurring at topographic boundaries. As usual the OS1.1 session also welcomes submissions that do not fit to any of the other special sessions; this includes the oceanography of the Pacific Ocean.

The rapid decline of Arctic sea ice in the last decade is a dramatic indicator of climate change.  The last 12 years have seen lower Arctic summer sea ice extents than in the previous 29 years of satellite records. The Arctic sea ice cover is now thinner, weaker and drifts faster. The ocean is also changing, the volume of freshwater stored in the Arctic and has increased as have the inputs of coastal runoff from Siberia and Greenland. Concurrently inflows from the Atlantic and Pacific Oceans have warmed. As the global surface temperature rises, the Arctic Ocean is speculated to become seasonally ice-free in the 21st century, which prompts us to revisit our perceptions of the Arctic system as a whole. What could the Arctic look like in the future? How are the present changes in the Arctic going to affect the lower latitudes? What aspects of the changing Arctic should future observations and modelling programs address? The scientific community is investing considerable effort in organising our current knowledge of the physical and biogeochemical properties of the Arctic, exploring poorly understood coupled atmosphere-sea-ice-ocean processes to improve prediction of future changes in the Arctic.
 
In this session, we invite contributions on a variety of aspects of past, present and future climates of the Arctic. We encourage submissions addressing interaction between ocean, atmosphere and sea ice and on studies linking changes in the Arctic to the global ocean. Submissions with a focus on emerging cryospheric, oceanic and biogeochemical processes and their implications are particularly welcome. The session promotes results from current Arctic programmes and discussions on future plans for Arctic Ocean modelling and measurement strategies. This session is cosponsored by the CLIVAR /CliC Northern Ocean Regional Panel (NORP) that aims to facilitate progress and identify scientific opportunities in (sub)Arctic ocean-sea-ice-atmosphere research.

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 years, several projects have been focused on the Atlantic circulation changes, for instance OVIDE, RACE, OSNAP, and ACSIS. 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

Invited Speakers: Professor Ric Williams, University of Liverpool, UK
Dr. Arnaud Czaja, Imperial College, London, UK

The climate state of the Atlantic Ocean is known to exert a huge control and hence a decisive role on the surface climate over the neighbouring continents as well as that of the Arctic Ocean. Heat in the South Atlantic converges from both the Pacific and Indian Oceans and is carried northward to higher latitudes along the dynamically-rich oceanic current systems to key deep water formation regions where the atmosphere is in direct contact with the deep ocean. Understanding what drives the variability of the Atlantic Ocean on multiple time scales and long-term trends is thus imperative for more confident predictions of the climate in the future decades.

This session will offer the opportunity to focus on the dynamics, variability and trends along the key climatic current systems from the South Atlantic to the North Atlantic and into Arctic Ocean and how they are influenced by local-, large- or global-scale processes or teleconnections. We aim to bring together researchers using observations, ocean models and state-of-the-art climate models.

We welcome presentations addressing:

- Sources, dynamics, pathways and meridional connectivity of heat and freshwater anomalies from lower to higher latitudes
- Impact of large- and global-scale atmospheric modes on Atlantic Ocean circulation
- Variations and long-term trends in Atlantic overturning circulation and relationship to sea-level and sea-ice change

Invited speaker: Penny Holliday, National Oceanography Centre, UK

The Southern Ocean, which stretches from Antarctic ice-shelf cavities to the northern fringe of the Antarctic Circumpolar Current, is a key region for water mass formation and for the uptake, storage and lateral exchanges of heat, carbon and nutrients. At present, the Southern Ocean acts as a sink of anthropogenic carbon and heat and as a source of natural carbon, but its role in future climate conditions remains uncertain. Processes on the Antarctic continental shelf also need to be better understood in order to assess the ocean’s role in Antarctic ice loss and the resulting meltwater impact on sea level. To reduce these uncertainties, it is critical to investigate the mechanisms underlying Southern Ocean's internal variability and its response to external forcing. Recent advances in observational technology, data coverage, circulation theories, and numerical models are providing a deeper insight into the three-dimensional patterns of Southern Ocean change. This session will discuss the current state of knowledge and novel findings concerning Southern Ocean circulation, water mass formation and pathways, mixing and mesoscale dynamics, ocean-ice-atmosphere interactions, sea ice changes, inflow of warm water to ice shelf cavities, and biological productivity, as well as the heat, nutrient and carbon budgets. This includes work on all spatial scales (from local to basin-scale to circumpolar) and temporal scales (past, present and future). We particularly invite cross-disciplinary topics involving physical and biological oceanography, glaciology, or biogeochemistry.

The seasonal reversal of monsoon winds and concurrent ocean currents, relatively deep thermocline along the equator due to the lack of steady easterlies, low-latitude connection to the neighboring Pacific and a lack of northward heat export due to the position of the Asian continent make the Indian Ocean unique among the other tropical ocean basins. These characteristics shape the Indian Ocean’s very dynamic intraseasonal, seasonal, and interannual variability, as well as its air-sea interactions. They also make the basin and its surrounding regions, which are home to a third of the global population, particularly vulnerable to anthropogenic climate change, and robust warming and trends in heat and freshwater fluxes have been observed in recent decades. 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 understanding and predicting the links between Indian Ocean variability and monsoon systems on (intra)seasonal to interannual timescales, interactions and exchanges between the Indian Ocean and other ocean basins, decadal variability and its prediction, response to climate change, extreme events, as well as interactions between physical, biogeochemical, and ecological processes. Contributions are also sought that address research on the Indian Ocean grand challenges, as formulated by the Climate and Ocean: Variability, Predictability, and Change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), and the International Indian Ocean Expedition 2 (IIOE-2) programs.

Observations and simulations of ocean circulation and marine atmosphere processes are rapidly growing for meso to basin scale, on diurnal to interannual scale. This session focuses on tropical and subtropical ocean dynamics as well as local interaction between the ocean and the overlying atmosphere from the equator to mid-latitudes. Relevant processes in the ocean include upper and deep ocean circulation variability, mild SST gradients to sharp fronts, eddies, filaments, tropical instability waves, warm pools, upper ocean various layers, cold tongues and eastern boundary upwelling. Regarding air-sea interactions, we seek studies that analyse the local to regional scales, and those discussing the conditions under which they may lead to a large-scale atmospheric response. Surface wind modulations, Madden-Julian Oscillation, cyclones, and convective systems, as well as scale interactions are welcome. In the extra-tropics, we seek also contributions on the role of extra-tropical fronts in regional and large-scale atmospheric circulation. We welcome contributions on how the air-sea interactions may shape modes of climate variability and determine regional climate sensitivity.

Highly productive Eastern Boundary Upwelling Systems (EBUS) play a key role in the global carbon and nitrogen cycles. They also sustain intense fishery activities that could be affected by climate change. EBUS are characterized by a complex interplay of biological, chemical and physical processes taking place in sediments, water column and at the air-sea interface. In particular, physical processes range from regional scales to mesoscale eddies, submesoscale filaments and fronts, down to internal waves and microscale turbulence. They drive the transport of solutes such as nutrients, carbon and oxygen, as well as particulate matter and living organisms. A recent improvement in computational power and new techniques such as multi-nesting approaches, made possible to increase the resolution of regional ocean models down to some hundred meters, allowing to resolve these processes on the fine scale. New observational techniques such as airborne, underway, and autonomous technologies allow for high-resolution adaptive multidisciplinary campaigns. Recent progress in biological/microbial techniques and application of new chemical sensor techniques allow deciphering of biogeochemical patterns with unprecedented high resolution.

Interdisciplinary observational and modeling studies investigating physical, biological and chemical aspects of the major EBUS are welcome. In particular studies which combine observational and modeling efforts, new data analysis techniques and focusing on climate change impacts are of interest.

NEWS: We are glad to announce that Monique Messie (https://www.mbari.org/messie-monique/) will give a solicited contribution to our session.

A wide range of processes in the earth system directly affect geodetic observations. This session invites a wide array of contributions which showcase the use of geodesy for Earth science and climate applications, providing crucial insights into the state and change of the earth system and/or understanding its processes.

Data driven quantification of water mass fluxes through boundaries of Earth’s different regions and spheres provides important insights to other geoscience communities and informs model validation and improvement. Changes in regional sea level and ocean circulation are observed by altimetry and gravimetry. Natural and anthropogenic alterations of the terrestrial water cycle lead to changes in river runoff, precipitation, evapotranspiration, and water storage which may cause surface deformation sensed by GNSS stations and InSAR measurements as well as mass/gravity changes observed by satellite/ground gravimetry. Mass changes in the ice sheets and glaciers are detectable by both geometrical and gravimetric techniques. And other novel applications of geodetic techniques are emerging in many fields.

In addition, individual sensor recordings are often affected by high-frequency variability caused by, e.g., tides in the solid Earth, oceans, and atmosphere and their corresponding crustal deformations affecting station positions; non-tidal temperature and moisture variability in the troposphere modifying microwave signal dispersion; rapid changes in the terrestrially stored water caused by hydrometeorologic extreme events; as well as swift variations in relative sea-level that are driven by mass and energy exchange of the global oceans with other components of the Earth system, which all might lead to temporal aliasing in observational records. 

This session invites a wide array of contributions which showcase the use of geodesy for Earth science and climate applications. This session aims to cover innovative ways to use GRACE, GRACE-FO and other low Earth orbiters, GNSS techniques, InSAR, radar altimetry, and their combination with in-situ observations. We welcome approaches which tackle the problem of separating signals of different geophysical origin, by taking advantage of model output and/or advanced processing and estimation techniques. Since the use of geodetic techniques is not always straightforward, we encourage authors to think of creative ways to make their findings, data and software more readily accessible to other communities in hydrology, ocean, cryospheric, atmospheric and climate sciences. With author consent, highlights from the oral and poster session will be tweeted with a dedicated hashtag during the conference in order to increase the impact of the session.

Changes in the Arctic and Antarctic climate systems are strongly related to processes in the boundary layer and their feedbacks with the free troposphere. An adequate understanding and quantification of these processes is necessary to improve predictions of future changes in the polar regions and their teleconnections with mid-latitude weather and climate, including meridional transport of heat, moisture and air pollutants. Processes include atmosphere-ocean-ice (AOI) interactions, such as physical and chemical snow processes (e.g. snow photochemistry), exchange of chemical constituents, sources of aerosol, polynya formation processes, sea ice production and bottom water formation, and cloud formation, which represent key processes for the atmosphere, ocean and the cryosphere. AOI interactions are also triggered by and have feedbacks with synoptic systems and mesoscale weather phenomena such as cold air outbreaks, katabatic winds and polar lows. Associated processes also include the effect of warm air advection and clouds on the surface energy budget and related boundary layer exchanges. Of increasing interest is the study of extremes such as heat waves and storms, but also extreme meridional transport events that can disturb the physical and chemical state of the high latitudes and may have a large impact on ecosystem changes. In addition, Arctic boundary-layer processes play an important role for local Arctic air pollution and for the health and ecosystem impacts thereof. In addition, understanding natural processes including AOI interactions is essential to understand of the background atmosphere to quantify the anthropogenic impacts. Shallow inversions, mostly during winter-time, lead to high air pollutant concentrations. Even though severe air pollution episodes are frequently observed in the Arctic, knowledge on urban emission sources and atmospheric chemical processing of pollution, especially under cold and dark conditions, are poorly understood.

This session is intended to provide an interdisciplinary forum to bring together researchers working in the area of boundary layer processes and high-latitude weather and climate (including snow physics, air/snow chemistry, and oceanography). Cryosphere and atmospheric chemistry processes (the focus of the IGAC/SOLAS activity “CATCH” and the IGAC/IASC activity “PACES”) are highly relevant to this session. We invite contributions e.g. in the following areas:

1. Observations and research on the energy balance, physical and chemical exchange processes, and atmosphere-ocean-ice (AOI) interactions including particle sources.
2. Results from high-elevation sites where similar processes occur over snow and ice.
3. Field programs, laboratory studies and observational studies (including remote sensing).
4. Model studies and reanalyses.
5. Advances in observing technology.
6. External controls on the boundary layer such as clouds, aerosols, radiation.
7. Teleconnections between the polar regions and mid-latitudes resulting in effects related to atmosphere-ice-ocean interactions as well as insights provided by monitoring of water vapor isotopes that shed light on air mass origins.
8. High-latitude urban air quality studies.

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: Cecile Penland (NOAA)

This session aims at bringing together multidisciplinary studies that address the current state of Arctic observing systems, including strategies to improve them in the future. We invite contributions covering atmosphere, ocean, cryosphere and terrestrial spheres, or combinations thereof, by use of remote sensing, in situ observation technologies, and modeling. Particular foci are placed on (i) the analysis of strengths, weaknesses, gaps in spatial/temporal coverage, and missing monitoring parameters in existing observation networks and databases, and (ii) studies describing the development and/or deployment of new sensors or observation platforms that extend the existing observing infrastructure with multidisciplinary measurements. This session will be supported by the EU-H2020 project INTAROS, and welcomes contributions from other pan-Arctic networks (e.g. INTERACT, GTN-P, NEON, ICOS, SIOS, IASOA, AOOS), multi-disciplinary campaigns (e.g. ABoVE, NGEE Arctic, Arctic Ocean 2018, RV Polarstern cruises) or databases.

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.

Global ocean circulation plays a key role in redistributing heat and in setting the oceanic carbon gradients, and thus modulates global climate on centennial to millennial time scales. With the emergence of new methods, greater spatial and temporal paleo-record coverage, and model simulations with numerous tracers, significant improvement has been made in the understanding of past oceanic changes and their impacts on global climate and the carbon cycle. New proxy approaches and increasing geographical coverage fill important gaps in the reconstruction of different ocean states and decrease uncertainty that arises from interpretations based on individual parameters and sites. Similarly, refined model approaches and increased computing capacity allow for the integration of important small- and intermediate scale processes as well as the direct inclusion of proxies in numerical models.

This session welcomes contributions on the role of the ocean circulation in Pleistocene climate and glacial-interglacial climate transitions. This comprises proxy and model assessments of ocean heat and carbon content, circulation strength and other climatic and biogeochemical parameters, including details on their regional variation, given they are relevant for understanding global processes. Furthermore, we encourage contributions of reconstructions that seem contradictory to the prevailing view insofar as their discussion may hint towards processes or pitfalls that are under appreciated and thus potentially important for future research.

ENSO is the dominant source of interannual climate variability in the tropics and across the globe. Understanding ENSO's dynamics, predicting El Niño and La Niña, and anticipating changes in ENSO's characteristics and impacts are thus of vital importance for society. This session invites contributions regarding the dynamics of ENSO, including multi-scale interactions; low frequency, decadal and paleo ENSO variability; ENSO theory; ENSO diversity; ENSO impacts on climate, society and ecosystems; ENSO teleconnections; seasonal forecasting of ENSO; and climate change projections of ENSO. Studies aimed at understanding ENSO in models of a range of complexity are especially welcomed, including analysis of CMIP model intercomparisons.

The millennial-scale variability associated with Dansgaard-Oeschger (D-O) cycles during the last glacial is known to have affected the climate system on a global scale. New high-resolution sediment and ice core proxy records document in increasing detail local and global variability of ice sheets, sea ice, as well as oceanic and atmospheric circulation during the D-O cycles. In addition, insights into the dynamics of the coupled ocean-cryosphere-atmosphere system during the millennial-scale climate cycles are emerging from improved model simulations. Documenting the precise timing and sequence of events in proxy records and capturing the processes responsible for the global pattern of rapid climate changes, which stretch from Greenland to Antarctica, remains a major challenge. However, understanding the underlying dynamics will provide fundamental information on the stability of the global climate system. In this interdisciplinary session, we welcome proxy- and model-based research that tests hypotheses on causes and processes behind the D-O events and helps understanding past, present and future changes to the climate system. The session is hosted by the ERC synergy project ice2ice.

Solicited talks include:
Oeschger medal lecture by Edward Brook, Oregon State University
Marlene Klockmann, Helmholtz-Zentrum Geesthacht Centre
Bradley Markle, University of Washington

To address societal concerns over rising sea level and extreme events, understanding the contributions behind these changes is key to predict potential impacts of sea level change on coastal communities and global economy, and is recognized as one of the Grand Challenges of our time by the World Climate Research Programme (WCRP). To continue this discussion, we welcome contributions from the international sea level community that improve our knowledge of the past and present changes in sea level, extreme events, and flooding, and produce improved predictions of their future changes. We welcome studies on various drivers of sea level change and linkages between variability in sea level, heat and freshwater content, ocean dynamics, land subsidence from natural versus anthropogenic influences, and mass exchange between the land and the ocean associated with ice sheet and glacier mass loss and changes in the terrestrial water storage. Studies focusing on future sea level changes are also encouraged, as well as those discussing potential short-, medium-, and long-term impacts on coastal and deltaic environments, as well as the global oceans.

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 (GIS) 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. The processes and feedbacks involved operate on all time scales and thus require several types of information: satellite and instrumental data, climate models, and reconstructions based on geological archives. In this session, we invite contributions from a range of disciplines and across time scales, including observational data, historical data, proxy data, model simulations and forecasts, for the past climate and the future. 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 Arctic-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.

The Arctic sea ice and high latitude atmosphere and oceans have experienced significant changes over the modern observational era. The polar climate is crucial for the Earth’s energy and water budget, and its variability and change have direct socio-economic and ecological impacts. Thus, understanding high-latitude variability and improving predictions of high latitude climate is highly important for society. Predictability studies indicate that decadal to multi-decadal variations in the oceans and sub-seasonal to multi-year sea ice variations are the largest sources of predictability in high latitudes. However, dynamical model predictions are not yet in the position to provide us with accurate predictions of the polar climate. Main reasons for this are the lack of observations in high latitudes, insufficient initialization methods and shortcomings of climate models in representing some of the important climate processes in high latitudes.
This session aims for a better understanding and better representation of the mechanisms that control high latitude climate variability and predictability in both hemispheres at sub-seasonal to multi-decadal time-scales in past, recent and future climates. Further, the session aims to discuss ongoing efforts to improve climate predictions at high latitudes at various time scales (as e.g. usage of additional observations for initialization, improved initialization methods, impact of higher resolution, improved parameterizations) and potential teleconnections of high latitude climate with lower latitude climate. We also aim to link polar climate variability and predictions to potential ecologocal and socio-economic impacts and encourage submissions on this topic.
This session offers the possibility to present results from the ongoing projects and research efforts on the topic of high-latitude climate variability and prediction, including, but not limited to Year of Polar Prediction (YOPP), and the ARCPATH-project (Arctic Climate Predictions - Pathways to Resilient, Sustainable Societies).

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).

Solicited talk:
Multi-year prediction of ENSO
By Jing-Jia Luo from the Institute for Climate and Application Research (ICAR), Nanjing University of Science Information and Technology, China

From interannual to multidecadal time scales, there is strong climate variability over both the tropical and extratropical regions of the globe. Several modes of both extratropical atmospheric circulation (NAM/AO, NPO, PNA, NAO, SAM/AAO, etc.) and sea surface temperature (AMO, PDO, North Pacific Gyre Oscillation (NPGO), North Atlantic tripole (NAT), etc.) have been proposed to explain the extratropical climate variability. These modes have profound impacts on the global and regional climates (i.e., temperature, precipitation, frequency of high-impact weather/climate events such as hurricane/typhoon, drought/flood and cold/heat waves, etc.). The associated dynamics and physical processes, such as the ocean-atmosphere interaction, coupled oceanic-atmospheric bridge, atmospheric internal dynamics and oceanic dynamics, are important for understanding the tropical-extratropical climate variability and thus have implications for the interannual to decadal predictability. However, the relevant dynamics and processes are not very well represented in current climate system models. Often this is due to a lack of observations of the processes being modelled. Contributions are welcome from, but not limited to, research on observational, theoretical and modeling studies on the following topics:
1. Physical processes and dynamics in the atmosphere/ocean and atmosphere-ocean coupling associated with the tropical-extratropical climate variability on time scales from years to multi-decades.
2. The impacts and teleconnections of the tropical-extratropical climate variability on a broad range of time scales and underlying physical mechanisms.
3. Comparison of observed and simulated tropical-extratropical climate variability and its climate impacts.
4. Predictability, prediction and projection of tropical-extratropical atmospheric and oceanic variability at various time scales.

In spring and summer 2018, Central and Northern Europe faced a severe drought with rainfall deficits beginning as early as April and lasting until late August in some regions (partly combined with a heat wave in July and August). Due to higher spring temperatures and high radiation the Baltic Sea showed a very unusal low pCO2 signal since late April and a spectacular summer bloom this year. The impact on terrestrial ecosystems became obvious through crop failure and forest fires. This transdiciplinary session calls for scientific results from Earth Observation showing the impact of the drought and for presentations from the interface between science a climate action e.g. adaptation strategies, questions on measuring, reporting and verification of inventories or general communication of climate change to societies.

Tipping elements in the Earth's climate system are continental-scale subsystems that are characterized by a threshold behavior. It has been suggested that these include biosphere components (e.g. the Amazon rainforest and coral reefs), cryosphere components (e.g. the Greenland and Antarctic ice sheets) and large-scale atmospheric and oceanic circulations (e.g. the thermohaline circulation, ENSO and Indian summer monsoon). Once operating near a threshold or tipping point, these components can transgress into a qualitatively different state by small external perturbations. The large-scale environmental consequences could impact the livelihoods of millions of people.

In this session, we aim to bring together experts presenting and discussing the state-of-the-art research on tipping elements in the Earth's climate system, both in empirical data and numerical modelling of past, present and future climate. Among other topics, issues to be addressed in this session include critical thresholds for specific tipping elements, typical time scales of tipping, interactions and feedbacks between tipping elements, the potential for tipping cascades as well as environmental and socio-economic impacts of tipping.

Contributions are invited on innovative observational, theoretical and modelling studies concerning physical processes in coastal and shelf seas. Processes can include hydrodynamics (e.g., waves, tides, currents and Stokes drift, upwelling, eddies, density structures), transport of material (e.g., sediments, contaminants, litter, nutrients), and morphodynamics and sea-bed structure (e.g., evolution of bed forms, banks, Holocene-Antropogene strata or basin shape). Study areas are envisaged between the base of the shelf break and the seaward limit of the surf zone, including tidal basins. However, contributions on processes outside these geographical limits will be considered where they significantly influence processes within these limits. Equally, contributions on climate dynamics, biogeochemistry, and man-made structures will be considered where they significantly influence, or are significantly influenced by, the processes aimed at in this session. In addition to the above, this session welcomes coastal and shelf seas related abstracts that do not fit into the more specialist sessions. Special attention will be given to interactions between physics and biology/biogeochemistry and to global to local scaling of processes, their relative importance, and the representation of these transitions in models. A subsession is envisaged on the Baltic Sea, with emphasis on the Baltic Earth programme, focusing on sea-level variability, salinity dynamics and water budget, biogeochemical feedbacks, extreme events and anthropogenically induced changes.

This session focuses on interaction between freshwater continental discharge and coastal sea from their initial mixing and transformation in river estuaries to formation of buoyant river plumes and their spreading in coastal and shelf areas. We will discuss dynamics of the related transport and mixing of freshwater discharge, as well as its influence on physical, biological, and geochemical processes at the continental shelf.
River plumes play an important role in land-ocean interactions. Despite their relatively small surface area and volume as compared to adjacent coastal sea, they significantly influence global fluxes of buoyancy, heat, terrigenous sediments, nutrients, and anthropogenic pollutants, which are discharged to the coastal ocean with continental runoff. River plumes are characterized by strong spatial inhomogeneity and high temporal variability caused by external forcing and mixing processes. Regional features (delta/estuary, enclosed bay/open sea, shoreline, bathymetry, etc.) also significantly influence morphology and behavior of river plumes. As a result, dynamics and variability of river plumes are key factors for understanding mechanisms of spreading, transformation, and redistribution of continental discharge and river-borne constituents in coastal sea and their influence on adjacent continental shelf.
The session will discuss recent advances in understanding mechanisms which govern dynamics and variability of river plumes and estuarine processes based on in situ measurements, satellite observations, and numerical modelling. The session will focus on influence of freshwater discharge and river plumes on stratification and circulation in esuaries and coastal areas, transport and fate of river-borne suspended and dissolved constituents (nutrients, terrigenous sediments, anthropogenic pollutants, litter), impact on coastal nutrient cycle and food webs, sediment deposition and seabed morphology.

The nearshore zone is one of the most dynamic places on earth. Here, the perpetual interaction between waves, tides, wind and the seabed drive the fluid motions that initiate sediment transport and, ultimately, shape the world’s coastal areas. The magnitudes and spatiotemporal scales at which these processes act vary tremendously, and understanding the small-scale processes that underlie large-scale coastal dynamics remains a challenge.
This session welcomes contributions that focus on small scale (from turbulence to mean flow, sand grains to ripples) physical processes in the nearshore zone of wave-dominated coasts. Ranging from approximately 10 m water depth up to the shoreline, this region comprises the shoaling, surf and swash zones. Topics include cross-shore and alongshore wave field evolution, wave-breaking and turbulence, swash-zone processes, cross-shore and alongshore current structures, extreme events, sediment mobilisation and transport, and biophysical interactions. This session will include abstracts describing field measurements, numerical and laboratory modelling, theoretical analysis, and model-data assimilation. We particularly welcome studies including innovative data collection approaches, or with a focus on uncertainties in measurements and predictions.

The solicited speaker in this session is dr. Marion Tissier (Delft University of Technology).

Oceanographic processes at coastal scales present a number of differences with respect to deep water oceanography, which result in higher prediction errors. In shallow water coastal domains the bottom topography, via the sea-bed boundary condition, exerts a strong control on the resulting wave and current fields. In addition to this, other factors need to be accounted for, such as the relevance of the tidal influence, stratification and mixing effects, land boundary condition (affecting the wind fields), the presence of distributed run off and point-wise river mouths. And yet it is in these coastal zones where the need for accuracy and reliability becomes crucial for planning socio-economic activities and for maintaining risk levels under present and future climate conditions.

A thorough characterisation of the physical processes taking place on the coastal region relies on the joint use of numerical modelling, in-situ observations and remote sensing, three approaches currently achieving rapid advances and which constitute the three basic pillars of this session. A coupled modelling approach to atmosphere, hydrodynamics and sediment transport, as well as the refinement of numerical strategies (nested meshes, finite-difference or finite-element discretization, variable grids, etc.), parameterizations and boundary conditions, can play a critical role in improving the quality of analyses and predictions. Marine observatories, providing the necessary information to drive and validate numerical models, are progressively aggregating into organised, trans-national infrastructures based on broadly accessible and interoperable data formats. The advent of new satellite capabilities (with increased resolution and enhanced technologies, like in the case of the Sentinel constellation) aiming at overcoming the typical limitations of remote sensing in coastal environments, allows starting a quantum leap in coastal oceanography. In fact, the joint use of these instruments can be particularly powerful for an increasing integration among the different aspects of coastal risk assessment, planning and response to climate change (as recommended by IPCC last reports).

This session proposes to discuss recent advances in these fields with emphasis on: integrated ocean-atmosphere-sediment modelling approaches and the physics of their coupling mechanisms; the hydrological, biogeochemical, geomorphological variability of coastal regions; the availability and use of coastal in-situ observations; and standards, procedures and data formats to make data ready for use in an integrated ocean processes monitoring system. We thus welcome presentations /posters also on: satellite/in-situ measurements, coastal assimilation, atmosphere-ocean-sediment model coupling and error/prediction limits as well as the contribution of coastal met-ocean science to operational oceanography. Applications to improve our knowledge on how these processes interact with coastal infrastructure or activities and applications of operational simulations combined with remote and in-situ data.

The session would like to overview recent developments and understanding, by observations and modelling, of the Southern European Seas (SES) general circulation, physical processes, biogeochemical interactions and their ecosystems. 

Themes of particular interest are: 
- Interaction of scales and processes in the SES: hydrodynamic and ecosystem interactions at multiple temporal and spatial scales (down to submesoscale), coastal processes and shelf-to-open sea interactions, straits dynamics, ocean response to atmospheric forcing, impact of environmental conditions on ecosystem functions from local to regional scales.

- Assessing, understanding and predicting the potential impact of climate change in the SES: long term trends, occurrence of extreme events, development of downscaled models at basin and regional scales, novel approaches to model marine ecosystems, ecosystem functions and biodiversity.

- Integrated Observing System in the SES: development of new sensors, scale of interests, development of advanced methodologies for upscaling local information, new satellite products, processes that need to be monitored, identification of data gaps (eg. observing system experiments). 

- Science-based Integrated management of the SES: support to Marine Spatial Planning and deployment of Marine Protected Areas , scenario studies, mapping of anthropogenic pressures, habitat and ecosystem services, potential support for nature-based solutions and/or sustainable exploitation of marine resource.

There is a global need for low carbon energy, and marine renewable energy could make a significant contribution to reducing greenhouse gas emissions and mitigation of climate change, as well as providing a high-technology industry. Marine renewable energy includes offshore wind, wave, tidal range (lagoons and barrages), and tidal-stream energy. Understanding the environment these marine renewable energy devices are likely to operate in is essential when designing efficient and resilient devices; furthermore, accurately charactering the resource, and likely impacts, is essential for the development of the marine renewable energy industry. This session is designed to share information on new research techniques and methods to better understand the resource, and interactions between energy extraction, the resource, and the environment. We welcome contributions on resource characterization, design considerations (e.g. extreme and fatigue loadings), and environmental impacts, at all timescales (ranging from turbulence to decadal) and all spatial scales (from device and array scales to shelf sea scales); including mapping tools, numerical modelling approaches, and observations. The session will also include studies of impacts, from physical and biological, to societal interactions (e.g. effects to tourism). These impacts include biological interactions with the resource and with the device. Research areas are envisaged to include but not restricted to: modelling and quantification of the interaction of the device to the marine environment (e.g. changes in hydrodynamics) as well as on the biology directly; ecological study designs and methods; new technologies for quantification; management of space; collision; noise; habitat change; community change for all trophic levels interaction.

Natural gas hydrates are solid inclusion compounds composed of water and gas. They form as methane hydrates under elevated pressure and lower temperature conditions in marine sediments along continental margins. They bind large volume of natural gas worldwide and may alter the strength of the upper sediment package along the margins based on their morphology, volume, and the stability conditions. Up to date, neither the quantification of gas hydrate resources nor the impact of gas hydrates on sediment stability or slope failures are well constrained. This is despite their importance for the usage of the continental slope and the exploration as well as exploitation of the unconventional hydrate reservoirs. Related studies are an essential component of current field studies, experimental research, modelling, and technical development.
This session aims at bringing together experts in these fields in order to exchange know-how as well as identify knowledge gaps. In this context we would like to invite contributions from studies in gas hydrate research as specified above.

This session provides a scientific platform for exchange of findings from research that addresses the entire continuum of river and sea. We invite studies across geographical borders, along the freshwater-marine water continuum, and interdisciplinary studies that integrate physical, chemical, biological, geological observations/experiments, and modelling, and those that span the traditional silos of natural and social sciences.
River-Sea-Systems comprise river catchments, estuaries/deltas, lagoons and the coastal seas. They are dynamic products of interacting environmental and socio-economic processes. River-Sea-Systems provide natural capital and related ecosystem services that are fundamental to societal wellbeing. These systems, however, face compounding pressures from natural forces such as climate change and natural hazards, and from anthropogenic forces like urbanisation, shipping, energy generation, industrial development, water abstraction and damming, operating at local, national and global scales. The resulting pressures contribute to societal challenges such as eutrophication, hypoxia, pollution, change in hydrodynamics and morphodynamics (including disturbed sediment balances), loss of biodiversity, habitat depletion, sea level rise, and ultimately loss of ecosystem services. This impacts not only on the ‘planet’ but also on ‘people’ and ‘profit’. These pressures are likely to increase in the future with implications throughout the river-sea continuum with uncertain consequences for the resilience of the socio-ecological system.
We need to fully understand how River-Sea-Systems function. How are River-Sea-Systems changing due to human pressures? What is the impact of processes in the catchment on marine systems function, and vice versa? How can we discern between human-induced changes or those driven by natural processes from climate-induced variability? What will the tipping points of socio-ecologic system states be and what will they look like? How can we better characterise river-sea systems from the latest generation Earth observation to citizen science based observatories. How can we predict short and long term changes in River-Sea-Systems to manage them sustainably? What is the limit to which it is possible to predict the natural and human-influenced evolution of River-Sea-Systems?
Which policy responses would be desirable from a scientific perspective and how will the gaps between the existing European environmental policies be bridged (e.g. Water Framework Directive 2000, Marine Strategy Framework Directive 2008 and EU biodiversity policies)? How will links be made to the UN 2030 Agenda’s Sustainable Development Goals 6 (Clean Water & Sanitation) and 14 (Life below Water)?
The increasing demand to jointly enable intensive human use and environmental protection in river-sea systems requires holistic and integrative research approaches with the ultimate goal of enhanced system understanding. It is becoming widely recognised that there is a need to study River-Sea-Systems as an entire continuum, to provide scientifically underpinned information to enable better-informed and holistically engaged environmental protection of River-Sea systems, to maintain their ecosystem functioning and thus their capacity to provide ecosystem services.

Climate change in the Mediterranean region poses critical environmental issues and can affect many sectors of human activities. Contrasting climate trends, levels of exposure and vulnerability are present across this region with associated potential conflicts. Climate research is expected to contribute an increasingly precise information on the future climate and impacts of climate change in this region. A large set of instrumental records and climate proxies allows in many areas of the Mediterranean region to bridge present trends and past climate over a wide range of timescales. This session encourages contributions adopting a multidisciplinary approach and it aims to promote a dialogue between climatologists and researchers interested on the impacts of climate on human and natural systems. It aims at including contributions describing new scientific findings on the climate of the Mediterranean region, its dynamics, variability, change, and studies of climate related impacts on societies and ecosystems. The session considers different time scales (from paleoclimate to future model projections), different components (atmosphere, ocean, land and its hydrology) and factors (chemical, biological, anthropic) as well as highlights of sub-regional hotspots and climate processes.

Natural hazards and climate change impacts in coastal areas
Coastal areas are vulnerable to ocean, atmospheric and land-based hazards. This vulnerability is likely to be exacerbated in future with, for example, sea level rise, increasing intensity of tropical cyclones, increased subsidence due to groundwater extraction. Drawing firm conclusions about current and future changes in this environment is challenging because uncertainties are often large. This calls for a better understanding of the underlying physical processes and systems. Furthermore, while global scale climate and detailed hydrodynamic modelling are reaching a mature development stage the robust assessment of impacts at regional and local scales remains in its infancy. Numerical models therefore play a crucial role in characterizing coastal hazards and assigning risks to them.

This session invites submissions focusing on assessments and case studies at global and regional scales of potential physical impacts of tsunamis, storm surge, sea level rise, waves, and currents on coasts. We also welcome submissions on near-shore ocean dynamics and also on the socio-economic impact of these hazards along the coast.

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.

The scopes of the session involve different aspects of large-amplitude wave phenomena in the Ocean (such as freak or rogue waves): surface and internal waves, and also waves trapped by currents and bathymetry. The session is focused on the understanding of the physical mechanisms which cause extreme events, and proposing appropriate mathematical models for their description and advanced methods for their analysis. An essential part of such studies are the results of verification of the new models and techniques versus laboratory and in-situ data. Special attention is paid to the description of the wave breaking process, and also large-amplitude wave interaction with coastal structures.

Tsunamis and storm surges pose significant hazards to coastal communities around the world. Geological investigations, including both field studies and modelling approaches, significantly enhance our understanding of these events. Past extreme wave events may be reconstructed based on sedimentary and geomorphological evidence from low and high energy environments, from low and high latitude regions and from coastal and offshore areas. The development of novel approaches to identifying, characterising and dating evidence for these events supplements a range of established methods. Nevertheless, the differentiation between evidence for tsunamis and storms still remains a significant question for the community. Numerical and experimental modelling studies complement and enhance field observations and are crucial to improving deterministic and probabilistic approaches to hazard assessment. This session welcomes contributions on all aspects of paleo-tsunami and paleo-storm surge research, including studies that use established methods or recent interdisciplinary advances to reconstruct records of past events, or forecast the probability of future events.


This session is a contribution to IGCP Project 639: Sea-Level Change from Minutes to Millennia http://sealevelchange.org/

Rock coasts occupy the majority of the World's shoreline and there continues to be increasing scientific interest in the geomorphology of these coasts. Contemporary rock coasts are also linked to geological and sea level records when shore platforms become marine terraces. This session includes any aspect of rock coasts including; geomorphology, processes (marine, subaerial and biological), geology (lithology, structure) and management of rock coasts (hazard and conservation). Processes studies, examples of modelling and the application of dating techniques are welcome. Papers detailing the development of novel techniques for the measurement of processes, erosion rates and morphology are also welcome. Finally papers that identify future trajectories for the management and geomorphology of rock coasts are encouraged.

Coastal zones worldwide face a great variety of environmental impacts associated to climate change, as well as increased anthropogenic pressures of coastal zone urbanization, rapid population growth and crucial shipping fairways. Strong interactions and feedbacks between hydrological, geomorphological, chemical and biological processes guide the morphological evolution of these sensitive coastal zones. Over the last decades coastal erosion has emerged as a widespread problem that causes shoreline retreat and irreversible land losses. Among the most affected and valuable natural systems of the coastal zone are estuaries and deltas. Inter- and supratidal habitats are threatened by expected changes under climate change, such as rising sea level at the mouth and larger variation in river discharge.
The human-induced solutions to cope with natural pressures using different types of hard engineering methods may often aggravate the problems, damaging natural landscape and coastal ecosystems in unexpected and unpredicted ways. Other negative impacts of human activities on littoral environments are chronic and punctual pollution of beaches, estuaries, river deltas, intertidal areas and coastal sediments with associated health risks for human beings. Chronic pollution is often observed in coastal areas close to factories, industries and human settlements - because of waste water discharges, punctual contamination is often linked to beach oiling. Therefore, assessing the impact of current and future climate change and anthropogenic pressure on the coastal zone is a complex task.
In this session we aim to bridge the gap between natural coastal zone dynamics and future response to human influence and climate change. We welcome subjects related to coastal geomorphology: evolution of coastal landforms, coastal morphodynamics, coastline alterations and various associated processes in the coastal zone, e.g. waves, tides and sediment drift, which shape coastal features and cause morphological changes.
The topics may include work on predictions of shoreline change, estuary and delta development and discussions on the effects of human activities and their continuing contribution to coastal changes. The session will also cover submissions on coastal vulnerability to the combined effects of natural and human-related hazards, any type of coastal and environmental sensitivity classifications, and risk assessments.

The Session is Sponsored by the Commission on Coastal Systems (CCS) of the International Geographical Union (IGU) (http://www.igu-ccs.org).

Coastal wetland ecosystems, such as salt marshes, mangroves, seagrasses and tidal flats, are under increasing pressure and threat from natural and anthropogenic processes such as land claim, altered sediment regimes, increased storm magnitude and frequency, and relative sea level rise. Consequently, these ecosystems are declining globally, with evidence of degradation and isolation across the full variety of coastal wetland habitats. These environments provide numerous ecosystem services, including flood risk mediation, biodiversity provision and climate change mitigation through carbon storage. There is, therefore, a need to understand current processes and interactions in these environments, and how these may change in the future due to both natural and anthropogenic influences. This is particularly the case in ‘managed’ and restored wetlands, where tidal and/or riverine regimes are re-introduced and coastal wetlands allowed to migrate inland in response to sea level rise for the provision of the desired ecosystem services to be preserved and/or restored.
This session will bring together studies of coastal wetland ecosystems within open coast, estuarine, lagoon and delta environments, to enhance the understanding of the services provided, interactions between hydrodynamic conditions, sediment and ecology, and best future management practices. Studies of all processes occurring within coastal wetlands are invited. This includes, but is not exclusive to, sediment dynamics, hydrology, hydrodynamics, morphological characterisation, geotechnical analysis, ecological change and evolution, impact of climate change, sea level rise, anthropogenic and management implications. Multidisciplinary approaches and studies of wetland restoration and habitat loss compensation schemes are particularly encouraged, along with global to regional assessments of wetland migratory potential; studies on wetland migration dynamics and the characteristics and functions of restored wetlands; and governance and policy contexts for wetland migration. This session aims to enhance our understanding of wetland management, processes, interactions and the wetlands’ ability to migrate inland, allowing for improvement of our ability to quantify the responses of coastal wetlands and their ecosystem services to future sea level rise and anthropogenic activity.

Examining coastal morphodynamics from the nearshore through to inland dune systems is fundamental in understanding their short- to long-term behaviour. Coastal processes operate across large spatial and temporal scales and therefore comprehending their resulting landforms is complex.

At the coast, dunes provide the physical barrier to flooding during high energy storms, while beaches and nearshore areas help dissipate storm impact through a series of dynamic interactions involving sediment transfers and at times rapid morphological changes. Investigation of complex interactions between these three interconnected systems has become essential for understanding coastal behaviour.

This session, sponsored by the IGU-UGI Commission on Coastal Systems, welcomes contributions from coastal scientists interested in the measurement and modelling of the nearshore 25-0 m zone (waves, currents and sediment transport) and terrestrial coastal processes (on beaches and dunes) and responses within the three sub-units at various scales. The session will highlight the latest research developments in this part of the planet's geomorphic system and facilitate knowledge exchange between the submerged and sub-aerial coastal zones.

Our two Solicited speakers this year are Adam Switzer (Nanyang Technological University, Singapore) on 'Investigating records of recent storms on a volcaniclastic barrier system in Bicol, Philippines' and Rob Young (Western Carolina University, USA) on 'Beach Nourishment as Storm Protection: Its Impact on Sediment Budgets and Ecosystems'.

The regional climate change assessment reports for the Baltic (BACC I and II) and North Sea regions (NOSCCA) have recently estimated the extent and impact of climate change on the environments of the North and Baltic Sea regions. A major outcome of these reports is the finding that climate change is one of multiple drivers, which have a continuing impact on terrestrial, aquatic and socio-economic (resp. human) environments. These drivers interact with regional climate change in ways, which are not completely understood.
This session invites contributions, which focus on the connections and interrelations between climate change and other drivers of environmental change, be it natural or human-induced, in different regional seas and coastal regions. Observation and modelling studies are welcome, which describe processes and interrelations with climate change in the atmosphere, in marine and freshwater ecosystems and biogeochemistry, coastal and terrestrial ecosystems as well as human systems. In particular, studies on socio-economic factors like aerosols, land cover, fisheries, agriculture and forestry, urban areas, coastal management, offshore energy, air quality and recreation, and their relation to climate change, are welcome.
The aim of this session is to provide an overview over the current state of knowledge of this complicated interplay of different factors, in different coastal regions all over the world.

Tsunamis can produce catastrophic damage on vulnerable coastlines, essentially following major earthquakes, landslides or atmospheric disturbances. After the disastrous tsunamis in 2004 and 2011, tsunami science has grown significantly, opening new fields of research for various domains, and also in regions where the tsunami hazard was previously underestimated.
Numerical modeling, complemented with laboratory experiments, are essential to quantify the tsunami hazard based. To this end, it is essential to rely on complete databases of past tsunami observations, including both historical events and results of paleotsunami investigations. Furthermore, a robust hazard analysis has to take into account uncertainties and probabilities with the more advanced approaches such as PTHA.
Because the vulnerability of populations, of infrastructures and of the built environment in coastal zones increases, integrated plans for tsunami risk prevention and mitigation should be encouraged in any exposed coastline, consistent with the procedures now in place in a growing number of Tsunami Warning System.
The NH5.1/OS2.22/SM3.11 Tsunami session welcomes contributions covering any of the aspects mentioned here, encompassing field data, regional hazard studies, observation databases, numerical modeling, risk studies, real time networks, operational tools and procedures towards a most efficient warning.
A focus on recent tsunami events all over the globe is encouraged (including Palu 28 September, Zakynthos 26 October, Tadine, New Caledonia, 5 December), as well as on the achievements of recent research projects.

The oceanic components of the global cycles of Carbon, Oxygen, Nitrogen and other macro/micronutrients are still not well constrained while they are undergoing unprecedented changes as a result of anthropogenic pressures. Studies of past and present observations as well as of future projections reveal biogeochemical perturbations at all spatio-temporal scales and emphasize complex interactions between ocean physics and biology, all of which are crucial to understand in order to anticipate their implications and future changes for biogeochemical cycling and ocean sustainability. Such knowledge is essential to the development of solutions for the monitoring of the ocean biogeochemical state, for the management of marine living resources and for various research as well as operational applications. This session will bring together researchers that use a range of novel techniques, including observations (e.g. in-situ measurements, remote sensing, global syntheses), experiments (e.g. laboratory and mesocosms), and modeling approaches (e.g. Earth System models, coupled biogeochemical-circulation models, theoretical models) to further improve our understanding of the biological carbon-pump, the biogeochemical cycles in the ocean and their connections to climate, as well as to increase the potential for operational applications.

We welcome contributions (1) dealing with the cycling of Carbon, Oxygen, and Nitrogen in the ocean, dissolved and particulate stoichiometry and elemental ratios, oceanic primary production, ocean acidification, exchange processes at the air-sea interface, role of sea-ice in global biogeochemical cycles and synthesis studies using global compiled data sets; (2) exploring innovative approaches to model-data fusion (e.g. novel methods in data assimilation, assimilation of data from novel in-situ or remote platforms, assimilation of up- or downstream products of ocean color remote sensing), model skill assessment, downscaling from large to regional domains, and case studies of research and operational applications (e.g. HAB prediction, episodic hypoxia, etc…); (3) focusing on a range of spatial scales (regional to global).

Deoxygenation in the marine environment is a critical global issue. Dissolved oxygen concentrations are indicators of ecosystem health as measures of biological productivity, remineralisation, and global climate trends. Oxygen deficient regions are present around the world, as persistent open ocean oxygen minimum zones or seasonal features in shelf seas.

Despite significant uncertainty under future climate scenarios, Earth system models predict deoxygenation across many ocean basins and shelf seas. This deoxygenation has a compound effect on oxygen deficient environments, causing shoaling, expansion, intensification and critical shifts in biogeochemical cycling pathways.

We must develop a better understanding of how physical, chemical and biological processes interact to impact low oxygen regions under changing oxygen conditions and climates. What are the interactions and feedbacks with biological communities and biochemical processes? How will these changes impact the marine environment at regional and global scales?

We invite contributions that investigate ocean deoxygenation and its physical, chemical and/or biological drivers, using observational or model-based approaches at regional or global scales.

Due to the growing pressures on marine natural resources and the ecosystem services demand, the interest of scientific and politic world is moving to ensure the conservation of marine ecosystems and environmental sustainable development of anthropogenic activities. Recently the principal European policies meet these issues, focusing on maintaining/ reaching the good environmental status (GES) of water bodies (WFD/MSFD) and solving the conflicts between anthropogenic pressures and marine ecosystems (MSP).
Some of the anthropogenic activities could have a potential impact on marine environment altering the marine ecosystems equilibrium. Since the dynamical processes influence the pollutants dispersion, it is compelling to analyse the ecosystems status through the study of abiotic variables distribution at proper spatial and temporal resolution.
From this perspective a large amount of data obtained by global observation systems (e.g. GOOS, EMODNET…) is needed to properly analyse the environmental quality both in the coastal and open ocean areas.
The session focuses on marine ecosystems, abiotic and biotic factors affecting their dynamics, highlighting the effects of anthropogenic impacts.
The following topics will be discussed: quantitative analysis of the effects of pollution on biota considering their natural and anthropogenic sources; benthic and pelagic community dynamics; economic evaluation of natural capital.
In this session multidisciplinary approaches using data coming from multiple sources (mathematical model, in-situ and remote observations) are encouraged.
Studies regarding the marine strategy descriptors, with the aim to develop methods, technologies and best practices to maintain/restore biodiversity and to guarantee a sustainable marine resources use, are also welcome.

Oceanographic modelling and monitoring are both widely used to study the pathways and fate of marine pollutants such as hydrocarbons, plastic litter, suspended sediments, radionuclides, etc. In this session, advanced 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.
Parcel trajectory numerical schemes, ensemble and multi-model methods, uncertainties estimation, risk algorithms, monitoring techniques 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 oil, floating debris and other pollutants?
What happens to the contaminants on the ocean’s surface and in the water column?
How do oil, marine litter and other pollutants interact with water and sediments?
Impacts of pollutants on the marine ecosystems and resilience to pollution events are also important subjects for discussion: What are the oil’s, plastics’, and sediments’s behavior in the water column, on various beach sediments, rocks and seabed? 
E.g., what is the biodegradation rate of oil droplets remaining in the water column and what are the controlling factors? What is the rate of aggregation, biofouling, degradation and fragmentation of plastics?
What is the rate of beaching and sedimentation of marine pollutants and what are the ways of entering the marine food chains (including human consumption)?

The coastal ocean has been increasingly recognized as a dynamic component of the global carbon budget. This session aims at fostering our understanding of the roles of coastal environments and of exchange processes, both natural or perturbed, along the terrestrial / coastal sea / open ocean continuum in global biogeochemical cycles. During the session recent advancements in the field of coastal and shelf biogeochemistry will be discussed. Contributions focusing on carbon and nutrient and all other element's cycles in coastal, shelf and shelf break environments, both pelagic and sedimentary, are invited.

This session is multidisciplinary and is open to observational, modelling and theoretical studies in order to promote the dialogue. The session will comprise subsections on coastal carbon storage, and on benthic biogeochemical processes.

This session is open to all contributions in biogeochemistry and ecology where stable isotope techniques are used as analytical tools, with a focus on stable isotopes of light elements (C, H, O, N, S, ...). We welcome studies from both terrestrial and aquatic (including marine) environments as well as methodological and experimental, theoretical and modeling studies that introduce new approaches or techniques (including natural abundance work, labeling studies, multi-isotope approaches, clumped and metal isotopes).

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.

This session will also provide an open forum for interdisciplinary discussions of the latest advances in oceanographic applications of autonomous underwater vehicles (AUVs), including their use and complementary in combination with other platforms. Examples of possible additional topics include physical (e.g. hydrology, hydrodynamics, acoustic, optic), geochemical (e.g. nutrients ) and biological (e.g. primary and secondary production, biomasses) variability of the ocean, ocean processes at different spatial and temporal scales (from ocean turbulence to basin-wide circulation), and interactions between the ocean, atmosphere and land.

Tides form a unique process in the Earth system because of their predictability, and because of their impact on many Earth system processes. This session is open to any aspect of tidal research, including the accuracy of present-day coastal, regional and global tide models, tidal dissipation, and the role of tides in geophysics, internal tides and their role in mixing the ocean and the impact on the global ocean circulation, secular and long-term changes in tides, insights on tidal variability from global geodetic observing techniques, and new techniques for measuring tides and analysing the data. We also welcome new findings on Earth and atmospheric tides, the role of tides in Earth’s ability to host and evolve life, tides in lakes, and planetary tides. The session is also intended to mark the 100th anniversary of the founding of the Liverpool Tidal Institute (LTI). The LTI for many years was the world centre for knowledge of the tides, with Joseph Proudman taking the lead in dynamical theories, and Arthur Doodson in the analysis of tidal information from around the world, and on tidal prediction. We therefore also welcome presentations on the history of tidal research.

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.

Invited speakers: Early career scientist Claudia Stephan (MPI), and Louis Gostiaux (CNRS / École Centrale de Lyon).

We invite presentations on ocean surface waves: their dynamics, modelling and applications. Wind-generated waves are 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.

Mesoscale and submesoscale structures such as fronts, meanders, eddies, and filaments are found worldwide, from the global ocean down to marginal seas. During the last years it has been shown that these features play a key role on the advection of heat, salt, biogeochemical properties, and on the enhancement of biological activity gathering all trophic levels. Due to their typical spatial and temporal scales, direct observations of these features remain currently an open challenge and their study requires a joint multi-platform effort combining in situ and remote sensing observations with theory and numerical models.

This session will provide a forum to properly address the new scientific advances associated with:
• Variability of (sub)mesoscale structures through observations (in situ and remote sensing), theory, and numerical simulations.
• 3D dynamics related to (sub)mesoscale features.
• Temporal and spatial interactions between different structures.
• Impact on mixing and transport of hydrographic properties.
• Physical and biogeochemical interactions.
• Limitations and improvements of the observational platforms and numerical simulations.
• A particular emphasis is put on challenges associated with the observation and numerical representation of subsurface (sub)mesoscale eddies.

Solicited speaker: Marina Levy et al., The role of submesoscale currents in structuring phytoplankton diversity

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.

Advanced remote sensing capabilities provide unprecedented opportunities for monitoring, studying, and forecasting the ocean environment. An integrated approach for synthesizing remote sensing data with in situ measurements and ocean models is highly desirable, both for physical and biological oceanography, polar oceanography and for marine gravity and geodesy on the regional, basin and global scales. This session provides a forum for interdisciplinary discussions of the latest advances in all aspects of oceanographic applications of remote sensing.

We welcome contributions on all aspects of the remote sensing of the ocean. Topics for this session include but are not limited to: physical oceanographic variability and interactions with the atmosphere, ocean currents, winds and surface waves, biological variability and the carbon cycle; sub-mesoscale processes, marine gravity and space geodesy, advances in the measurement and interpretation of the ocean surface salinity, and new instrument and techniques development in ocean remote sensing. Applications of multi-sensor observations to study ocean and climate processes and applications using international (virtual) constellations of satellites are also welcome.

Monitoring, in the form of time series data, or of repeated observation and sampling, acquired at fixed point observatories or using mobile platforms and research vessels, is essential to understand oceanic processes from the surface to the oceanic sub-bottom. In this session, we welcome presentations that demonstrate the use of such monitoring results to address physical, chemical, biological and geological processes in the water column and at the seafloor. Multidiciplinarity, the use of several sets of complementary data, and an emphasis on the interactions between the hydrosphere, biosphere and geosphere are particularly welcome. We also welcome presentations on new ocean monitoring experiments, and on innovative technologies for marine observatories. This session is sponsored by the EMSO-ERIC.

The Copernicus Marine Environment Monitoring Service (CMEMS) provides regular and systematic reference information on the physical state, variability and dynamics of the ocean and marine ecosystems for the global ocean and the European regional seas. This capacity encompasses the description of the current situation (analysis), the variability at different spatial and temporal scales, the prediction of the situation a few days ahead (forecast), and the provision of consistent retrospective data records for recent years (re-analysis and reprocessed datasets). CMEMS provides a sustainable response to European user needs in four areas of benefits: (i) maritime safety, (ii) marine resources, (iii) coastal and marine environment, (iv) weather, seasonal forecast and climate.

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; coupling with sea-ice, atmosphere & waves; data assimilation both for physics and biogeochemistry).

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 and (iii) on the monitoring and long-term assessment of the ocean physical and biogeochemical states.

Presentations should not be 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 on ocean model forcing from river discharge of freshwater and nutrients), as well as presentations on the use of Sentinel products.

Plastic contamination has been reported in all realms of the environment from the tropics to the polar oceans. The consequences of this contamination may be severe for ecosystems and could adversely affect ecosystem services such as fisheries and even human health. Our poor knowledge of plastics sources, their composition, sizes, pathways, hot spots of accumulation and ultimate fate prevents an assessment of environmental risks 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 combined with computational models from their sources on land to rivers, estuaries, oceans and sea ice. This requires improved standardized accurate observations and the development of advanced modelling capabilities to quantify and predict contamination levels.

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 framework to advise legislators and industry on the best ways to reduce the risks of serious damage from this contaminant.

This session will draw together data on plastic contamination across all sizes of plastics, from nano- and micro-plastics to large plastic fragments, and across all environments and locations. It will combine 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 new methods and field 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.

Invited speaker: Prof. Dr. Erik van Sebille

Physical processes of Air-Sea Interaction and their representation

This session aims at fostering exchanges and discussions on the physical processes at work at the air-sea interface, their observation, and their representation in coupled numerical models.

Examples of such processes are sun-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. Surface temperature and salinity fronts, 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 and water 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 campaigns such as (but not limited to) SPURS-2, YMC, or PISTON, or on 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.

Geophysical Fluid Dynamics (GFD) deals with various aspects of the mathematical descriptions of rotating stratified fluids starting from the physical laws of hydro-thermo-dynamics. Physicists and Mathematicians originating from various disciplines developed physical and numerical models with increasing complexity, adding to our fundamental understanding of such flows and thereby unifying these fields. Today GFD is a truly interdisciplinary field of its own, which encompasses multiscale flows of planetary atmospheres and oceans, their weather and climate, and the motions of 'the solid Earth'.

In this session we invite contributions expanding our understanding of the complex behavior of geophysical flows and Turbulence, presenting novel techniques that either facilitate a deeper understanding or improve the efficiency of numerical procedures involved, and/or reviewing major advances in a particular aspect of geophysical fluid dynamics. In these contexts, the role of waves (non-linear, inertial, internal, vorticity or helicity waves), turbulence and transport are an important factor in the understanding of GFD flows.

The interdisciplinary character of dynamical and computational aspects of this session encourages an exchange of ideas and contributions across various fields, such as meteorology, oceanography, astrophysics, geological fluid dynamics, applied mathematics, and computational fluid dynamics with applications to ocean and atmosphere and their Biological influences.
The recent improvements in Remote Sensing of the Earth and other Planets also allows comparison with Laboratory and Numerical Experiments involving Stratification, Rotation, Magnetic Fields, body forces, etc... Other NP6.x sessions address complementary aspects affecting Geo-Astrophysical Turbulence.

The energy of a closed system is steady. It is not lost but rather converted into other forms, such as when kinetic energy is transferred into thermal energy. However, this fundamental principle of natural science is often still a problem for climate research. For example, in case of the calculation of ocean currents and circulation, where small-scale vortices as well as diapycnal mixing and the deep convection processes they induce, need to be considered, to compute how heat content is redistributed along the entire water column and how such processes may change in the future. Similarly, in the atmosphere, the conversion of available potential energy into kinetic energy is the key driver of atmospheric dynamics at a variety of scales, from the zonal-mean general circulation to mesoscale convection. Local turbulent processes can drive larger movements and waves on a larger scale can disintegrate into small structures. All these processes are important for the Earth’s climate and determine its evolution in the future.

How exactly the energy transfers between waves, eddies, local turbulence and mixing in the ocean and the atmosphere works, often remains unclear. This session wants to discuss this by inviting contributions from oceanographers, meteorologists, climate modelers, and mathematicians. We are particularly interested in coupled atmosphere-ocean studies, we are also aiming at filling a knowledge gap on deep ocean processes, as well as novel subgrid-scale parameterizations, and studies of the energy budget of the complex Earth system, including the predictability of the global oceanic thermohaline circulation and thus climate variability.

Invited speakers:
Martin Wild, ETH, Zürich, Switzerland
Raffaele Ferrari, MIT, USA
Robert Weller, WHOI and OOI Research Infrastructures, USA

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-current-turbulence interactions, , including wave and current stability, 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.

Weather and climate models used for weather forecasts, seasonal predictions and climate projections, are essential for decision making on timescales from hours to decades. However, information about future weather and climate relies on complex, though imperfect, numerical models of the Earth-system. Systematic biases and random errors have detrimental effects on predictive skill for dynamically driven fields on weather and seasonal time scales. Biases in climate models also contribute to the high levels of uncertainty in many aspects of climate change as the biases project strongly on future changes. A large source of uncertainty and error in model simulations is unresolved processes, represented through parameterization schemes. However, these errors typically materialize at large spatial scales. Our physical understanding of the mechanical and dynamical drivers of these large-scale biases is incomplete. Incomplete mechanistic understanding hinders marked improvements in models, including identification of the parameterizations most in need of improvement.

Understanding and reducing the errors in weather and climate models due to parameterizations and poorly represented mesoscale to regional scales processes is a necessary step towards improved weather and climate prediction. This session aims to bring together these two perspectives, and unite the weather and climate communities to address this common problem and accelerate progress in this area.

This session seeks submissions that aim to quantify, understand, and reduce sources of error and bias in weather and climate models. Themes covered in this session include:

- Theory and development of parameterization. Impact on errors in mean state, model variability and physical process representation;

- Improved physical understanding of the drivers of large-scale biases including the use of process studies, idealized modeling studies and studies with strong observational components;

- Growth and propagation of error and bias in models; model errors across temporal and spatial scales; dependency of errors on model resolution and the development of scale-aware parameterization schemes;

- Use of “emergent constraints” to relate present day model biases with the climate change signal;

- Understanding and representing random model error.

Invited presentations: Felix Pithan (AWI) and Bob Plant (University of Reading)

Lead Convenors: Hannah Christensen and Stefan Sobolowski
Co-convenors: Craig Bishop, Ariane Frassoni, Daniel Klocke, Erica Madonna, Isla Simpson, Keith Williams, Giuseppe Zappa

The quality of predictions of weather and climate depends on both resolution and complexity of the models that are used. However, resolution and complexity are limited by the computational performance that is available on today's supercomputers. While weather and climate models run on some of the fastest supercomputers of the world, models typically fail to run close to peak performance such that there is still room for a significant speed-up if efficiency is improved. The increase in parallelisation in high performance computing and the availability of various computing platforms is imposing significant challenges for the community to find the optimal hardware/model configuration and to achieve the best performance. On the other hand, the evaluation of high resolution simulations is often tedious due to large data volumes, limited statistic that is affordable and changed model behaviour that needs to be studied (e.g. if convection or eddies are resolved explicitly or if non-hydrostatic equations need to be used).
These challenges can only be addressed appropriately in a close collaboration between Computing and Earth System Scientists. This session aims to bring together scientists who run and evaluate atmosphere and ocean models with high resolution and complexity as well as scientists who enable these models to run as efficiently as possible on existing and future high performance computing architectures (regarding both model development and model optimisation). The session will also be an opportunity for scientists from the EU projects PRIMAVERA, ESCAPE and ESiWACE as well as HighResMIP from CMIP6 to meet and interact.

V. Balaji from Princeton University will be our keynote speaker invited by the ESiWACE EU Horizon2020 COE (grant number 675191).

Many situations occur in Geosciences where one wants to obtain an accurate description of the present, past or future state of a particular system. Examples are prediction of weather and climate, assimilation of observations, or inversion of seismic signals for probing the interior of the planet. One important aspect is the identification of the errors affecting the various sources of information used in the estimation process, and the quantification of the ensuing uncertainty on the final estimate.

The session is devoted to the theoretical and numerical aspects of that broad class of problems. A large number of topics are dealt with in the various papers to be presented: algorithms for assimilation of observations, and associated mathematical aspects (particularly, but not only, in the context of the atmosphere and the ocean), predictability of geophysical flows, with stress on the impact of initial and model errors, inverse problems of different kinds, and also new aspects at the crossing between data assimilation and data-driven methods. Applications to specific physical problems are presented.


Solicited Speakers
Olivier Pannekoucke (Météo-France, Toulouse)
Manuel Pulido (University of Reading)

In both climate modelling and numerical weather prediction, numerical models of the Earth System are used extensively. For the both the atmosphere and ocean such models consist of a fluid dynamics solver (dynamical core) coupled to physics parameterizations to represent processes that occur below the grid scale (physics). Over time these models have become capable of sophisticated simulations, incorporating such features as multi-scale prediction, structure-preserving discretization and a detailed treatment of physics. New work is constantly being undertaken to improve the accuracy and efficiency of these models, both the dynamical core and the physics.

This session encompasses the development, testing and application of novel numerical techniques for Earth system models, including new discretizations, test cases, advection schemes, vertical discretizations, adaptive multi-scale models, physics-dynamics coupling, global and regional climate and NWP models, structure-preserving discretizations and parameterizations (that are not covered in other sessions).

Data assimilation is becoming more important as a method to make predictions of Earth system states. Increasingly, coupled models for different compartments of the Earth system are used. This allows for making advantage of varieties of observations, in particular remotely sensed data, in different compartments. This session focuses on weakly and strongly coupled assimilation of in situ and remotely sensed measurement data across compartments of the Earth system. Examples are data assimilation for the atmosphere-ocean system, data assimilation for the atmosphere-land system and data assimilation for the land surface-subsurface system. Optimally exploiting observations in a compartment of the terrestrial system to update also states in other compartments of the terrestrial system still has strong methodological challenges. It is not yet clear that fully coupled approaches, where data are directly used to update states in other compartments, outperform weakly coupled approaches, where states in other compartments are only updated indirectly, through the action of the model equations. Coupled data assimilation allows to determine the value of different measurement types, and the additional value of measurements to update states across compartments. Another aspect of scientific interest for weakly or fully coupled data assimilation is the software engineering related to coupling a data assimilation framework to a physical model, in order to build a computationally efficient and flexible framework.

We welcome contributions on the development and applications of coupled data assimilation systems involving models for different compartments of the Earth system like atmosphere and/or ocean and/or sea ice and/or vegetation and/or soil and/or groundwater and/or surface water bodies. Contributions could for example focus on data value with implications for monitoring network design, parameter or bias estimation or software engineering aspects. In addition, case studies which include a precise evaluation of the data assimilation performance are of high interest for the session.

From the perspective of Earth System predictions, the use of machine learning, and in particular deep learning, is still in its infancy. There are many possible ways how machine learning could improve model quality, generate significant speed-ups for simulations or help to extract information from numerous Earth System data, in particular satellite observations. However, it has yet to be shown that machine learning can hold what it is promising for the specific needs of the application of Earth System predictions. This session aims to provide an overview how machine learning can/will be used in the future and tries to summarise the state-of-the-art in an area of research that is developing at a breathtaking pace.

Airborne observations are one major link to get an overall picture of processes within the Earth environment during measurement campaigns. This includes application to derive atmospheric parameters, surface properties of vegetation, soil and minerals and dissolved or suspended matter in inland water and the ocean. Ground based systems and satellites are other key information sources to complement the airborne data sets. All these systems have their pros and cons, but a comprehensive view of the observed system is generally best obtained by means of a combination of all three. Aircraft operations strongly depend on weather conditions either to obtain the atmospheric phenomenon of interest or the required surface-viewing conditions and hence require sophisticated flight planning. They can cover large areas in the horizontal and vertical space with adaptable temporal sampling. Future satellite instruments can be tested and airborne platforms and systems are widely used in the development process. The validation of operational satellite systems and applications is a topic that has come increasingly into focus with the European Copernicus program in recent years. The large number of instruments available on aircraft enables a broad and flexible range of applications. The range includes sensors for meteorological parameters, trace gases and cloud/aerosol particles and more complex systems like high spectral resolution lidar, hyperspectral imaging at wavelengths from the visible to thermal infra-red and synthetic aperture radar. The development of smaller state-of-the-art instruments, the combination of more and more complex sets of instruments simultaneously on one platform, with improved accuracy and high data acquisition speed together with high accuracy navigation and inertial measurements enables more complex campaign strategies even on smaller aircraft or unmanned aerial vehicles (UAV). This will further increase the capabilities of the existing fleet of airborne research.

This session will bring together aircraft operators and the research community to present
• an overview of the current status of airborne related research
• recent airborne field campaigns and their outcomes
• multi-aircraft campaigns
• satellite calibration/validation campaigns
• sophisticated airborne instrument setups and observations
• advanced airborne instrument developments
• UAV applications
• future plans for airborne research

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot aboard. Originating mostly from military applications, their use is rapidly expanding to commercial, recreational, agricultural, and scientific applications. Unlike manned aircraft, UAVs were initially used for missions too "dull, dirty, or dangerous" for humans. Nowadays however, many modern scientific experiments have begun to use UAVs as a tool to collect different types of data. Their flexibility and relatively simple usability now allow scientist to accomplish tasks that previously required expensive equipment like piloted aircrafts, gas, or hot air balloons. Even the industry has begun to adapt and offer extensive options in UAV characteristics and capabilities. At this session, we would like people to share their experience in using UAVs for scientific research. We are interested to hear about specific scientific tasks accomplished or attempted, types of UAVs used, and instruments deployed.

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. Many such processes are hazards to coastal populations and offshore installations, and their understanding constitutes a key objective of national and international research programmes and IODP expeditions. 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, 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.

This interdisciplinary session aims to examine 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, 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. 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 abyss plains). Datasets of any scale, from satellite-predicted depth to ultra high-resolution swath bathymetry, sub-surface imaging and sampling, are anticipated.

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

Marine geological processes cover a range of different disciplinary fields and their understanding usually requires an interdisciplinary approach. The interaction of geological, physical oceanographic, chemical and biological mechanisms in marine geological processes ranging from sediment erosion and deposition, to hydrothermal and fluid flow systems, to early diagenesis and geomicrobiology, is of specific interest. Such processes may take place in shallow or deep, in tropical and glacial environments, and they may be natural or partly human-influenced. Climate-induced perturbations in marine geological processes have occurred in present and past, and potentially will also occur in the future. Several of these processes may also have a profound human impact, such as tsunamis generated by tectonic or mass-slumping events, coastal erosion in response to changed currents or river discharge, and sediment gravity flow in deep waters affecting human infrastructures. /We encourage comprehensive and interdisciplinary abstracts within the broad field of marine geology and with direct relevance to marine processes or deposits concerned with rocks, sediments, and geo-physical and geo-(bio)chemical processes that affect them.

The session gathers geoscientific aspects such as dynamics, reactions, and environmental/health consequences of radioactive materials that are massively released accidentally (e.g., Fukushima and Chernobyl nuclear power plant accidents, wide fires, etc.) 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 chemical/biological/electrical reactions chains in the environment. Thus, the radioactive contamination problem is multi-disciplinary. In fact this topic involves regional and global transport and local reactions of radioactive materials through atmosphere, soil and water system, ocean, and organic and ecosystem, and its relation with human and non-human biota. The topic also involves hazard prediction and nowcast technology.

By combining >30 year (halftime of Cesium 137) monitoring data after the Chernobyl Accident in 1986, >5 year dense measurement data by the most advanced instrumentation 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.

State-of-the-art environmental research infrastructures become increasingly complex and costly, often requiring integration of different equipment, services, and data, as well as extensive international collaboration. Clear and measurable impact of the research Infrastructures is therefore needed in order to justify such investments (from member states and the EU) - whether it is an impact in terms of knowledge, developments in the environmental field of science, new innovative approaches, capacity-building or other socio-economic impacts. Moreover, improving the impact supports the long-term sustainability of the research infrastructures.

This session aims at discussing how to best monitor, interpret, and assess the efficiency and impact of environmental and Earth system research infrastructures. Even more importantly, the session seeks a breadth of contributions, with focus on ways to increase and improve the impact of research infrastructures, not only through the scientific outcomes they produce, but also, for example, through increasing the number of touchpoints with other actors in the society, or awareness of the services they offer- whether this is enhanced by lobbying, direct cooperation with industrial partners, or any other action. Talks on how to enhance the impact through the strategic communications activities are especially welcome.

The session presents the state of art information systems in oceanography (metadata, vocabularies, ISO and OGC applications, data models), interoperability (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 2019 session should provide new ideas on the interoperability issues deriving from different sources of data and new data streams.
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. The session aims also to create a link to the important initiatives on ocean literacy. 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.

Plastic pollution is recognized as one of the most serious and urgent problems facing our planet. Rates of manufacture, use and ultimately disposal of plastics continue to soar, posing an enormous threat to the planet’s oceans and rivers and the flora and fauna they support. There is an urgent need for global action, backed by sound scientific understanding, to tackle this problem.

This Union Symposium will address the problems posed to our planet by plastic pollution, and examine options for dealing with the threat.

Satellite data provides information on the marine environment that can be used for many applications – from water quality and early warning systems, to climate change studies and marine spatial planning. The most modern generation of satellites offer improvements in spatial and temporal resolution as well as a constantly evolving suite of products.

Data from the European Union Copernicus programme is open and free for everyone to use however they wish - whether from academic, governance, or commercial backgrounds. The programme has an operational focus, with satellite constellations offering continuity of service for the foreseeable future. There is also a growing availability of open source tools that can be used to work with this data.

This short course is an opportunity to learn about the data available from the Copernicus Sentinel 3 satellite, and then, with support from marine Earth Observation experts, to develop your own workflows for using data from the EUMETSAT Copernicus Marine Data Stream and Copernicus Marine Environment Monitoring Service. The sessions will be interactive, using the WeKEO DIAS hosted processing, Sentinel Applications Platform (SNAP) software, and Python programming. No experience is necessary as various exercises will be provided for a wide range of skill levels and applications, however participants should bring their own laptops and be prepared to install open source software in advance.

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 behaviour 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. Registration is not needed, but indication of interest would be helpful for planning purposes.

Part 1 (2 hours) will have the following learning objectives:
• Equilibrium thermodynamics, master thermodynamic potentials, partial thermodynamic properties
• Interdependence of energy conservation and irreversible entropy production
• Mutually consistent definitions of heat and work in the atmosphere and oceans
• Convexity of the internal energy and the concept of exergy and available potential energy (APE). Local versus global theories of APE. Problems related to the definition and construction of reference states and of the ‘environment’.
• Standard and non-standard theories of irreversible processes. Are all irreversible processes necessarily dissipative? Irreversibility parameter.
• Non-equilibrium theory of sensible and latent heat fluxes at the air-sea interface, reversible and irreversible phase changes.
• Theories for the thermodynamic efficiency of the atmospheric and oceanic heat engines: APE versus entropy-based Carnot approaches. Does humidity really make the atmospheric heat engine less efficient? Maximum work versus maximum power.
• Exact partitions of potential energy into sign-definite components. Applications to exact mean/eddy partitions. Concepts of local baroclinic life cycle.

Part 2 (1 hour) will illustrate practical applications rooted in recent research and will cover topics such as:
• Means of energy exchange throughout the atmosphere and in the oceans
• Representation of irreversible processes in climate models.
• Importance of extratropical eddies in shaping the meridional energy transport, and how this links to the general circulation of the atmosphere
• Link to observations, consistency of current climate models with theory. Using theory to improve climate models in the future.

Data assimilation combines observational data with a numerical model. It is commonly used in numerical weather prediction, but is also applied in oceanography, hydrology and other areas of Earth system science. By integrating observations with models in a quantitative way, data assimilation allows to estimate model states with reduced uncertainty, e.g. to initialize model forecasts. Also, data assimilation can estimate parameters that control processes in the model or fluxes, which can be difficult or impossible to measure. As such, data assimilation can use observations to provide information about non-observable quantities if the model represents those. The combination of modelled and observed data requires error estimates for both sources of information. In ensemble data assimilation the error in the model state is estimated by an ensemble of model state realizations. This ensemble not only provides estimates of uncertainties, but also of cross-correlations between different model variables or parameters. The uncertainty estimate from the ensemble is then used by the assimilation method, and the most widely known is the ensemble Kalman filter.

To simplify the implementation and use of ensemble data assimilation, the Parallel Data Assimilation Framework - PDAF - has been developed. PDAF is a freely available open-source software (http://pdaf.awi.de) that provides ensemble-based data assimilation methods like the ensemble Kalman filter, but also allows to perform pure ensemble simulations. PDAF is designed such that it can be used from small toy problems running on notebook computers up to high-dimensional Earth system models running on supercomputers.

This course is both for the novices as well as for data-assimilation experts. It will be useful for novices who have a modelling application and observations and are interested in applying data assimilation, but haven't found a starting point yet. Data-assimilation experts who want to enhance the performance of their applications, or are keen to accelerate development of new data-assimilation methods and new applications will also benefit from the course.

The course will first provide an introduction to the ensemble data assimilation methodology. Then, it will explain the implementation concept of PDAF and finally provide a hands-on example of building a data assimilation system based on a numerical model. This practical introduction will prepare the participants to build a data assimilation system for their numerical models with PDAF and hence provide a quick start for applying ensemble data assimilation to their individual problems.

Participants are invited to bring their own notebook computer to run the hands-on examples themselves. For this, a Fortran compiler and the BLAS and LAPACK libraries are required. Matlab or Python would also be handy for plotting. Given the overall limited capacity of the Wifi network during the conference, it is recommended that you download PDAF from http://pdaf.awi.de before the short course if you like to do the hands-on example on your own notebook computer.

This year marks the 250th anniversary of the birth of Alexander von Humboldt (1769-1859), the intrepid explorer of the Andes and other regions in the world, and the most famous scientist of his time. Alexander von Humboldt is perhaps best known for his radical new vision of nature as a complex and interconnected global force, thereby becoming the founder of the field of biogeography and laying the ground for modern Earth-System Science approaches. It seems fitting to pay tribute to Alexander von Humboldt’s legacy by reviewing the state of the art in studies of the coupled lithosphere – atmosphere – hydrosphere – biosphere system with a focus on the Andean mountain belt. The Andes have become one of the main natural laboratories in the world to explore these questions and many recent studies have addressed its tectonic and geodynamic evolution, but also the two-way couplings between surface uplift, climatic evolution and biodiversity in the Andes and its foreland. This Union Session will bring together world-leading specialists on these questions with the aim to shed light on both suspected and unexpected couplings in the system.

Over the whole Earth history, the climate has encountered tipping points, shifting from one regulated system to the other. This tilting motion affects both climate and the carbon cycle and has played a major role in the evolution of the Earth climate, at all timescales. Earth History has been ponctuated by large climate changes and carbon cycle reorganizations, from large climate variations occurring in deep times (snowball events, terrestrialisation, Mesozoic and early Cenozoic warm episodes, quaternary glacial cycles…) to past and on-going abrupt events. Many potential triggers of those climate and carbon cycle shifts have been proposed and tested through modeling studies, and against field data, such as those directly or indirectly linked with tectonics (plate motion, orogenesis, opening/closing of seaways, weathering…) and orbital forcing. Given that the Earth climate is currently experiencing an unprecedented transition under anthropogenic pressure, understanding the mechanisms behind the scene is crucial.

Our aim is to point out the most recent results concerning how a complex system as the climate of the Earth has undergone many tipping points and what is the specificity of the future climate changes. Therefore, within this session, we would like to encourage talks discussing advances in our record and modeling of the forces triggering and amplifying the changes of Earth climate and carbon cycle across spatial and temporal scales.

In today’s changing world we need to tap the potential of every talented mind to develop solutions for a sustainable future. The existence of under-representation of different groups (cultural, national and gender) remains a reality across the fields of science, technology, engineering, and mathematics (STEM fields) around the world, including the geosciences. This Union Symposium will focus on remaining obstacles that contribute to these imbalances, with the goal of identifying best practices and innovative ideas to overcome obstacles.

EGU is welcoming six high-level speakers from the funding agencies and research centres on both sides of the Atlantic related to geosciences to present efforts and discuss initiatives to tackle both implicit and explicit biases. Speakers are:

Jill Karsten, AGU Diversity and Inclusion Task Force (confirmed)
Erika Marín-Spiotta, University of Wisconsin - Madison (confirmed)
Daniel Conley, Lund University (confirmed)
Giulio di Toro, University of Padua (confirmed)
Liviu Matenco, Utrecht University (confirmed)
Barbara Romanowicz, European Research Council (confirmed)

Atmospheric composition matters to climate, weather forecasting, human health, terrestrial and aquatic ecosystems, agricultural productivity, aeronautical operations, renewable energy production, and more. Hence research in atmospheric composition is becoming increasingly cross-cutting and linked to many disciplines including climate, biogeosciences, hydrology, natural hazards, computer and data sciences, socio-economic studies and many others. There is a growing need for atmospheric composition information and an improved understanding of the processes that drive changes in the composition and resulting impacts. While atmospheric composition research is advancing rapidly, there is a need to pay more attention to the translation of this research to support societal needs. Although translational research is a major focus of the health sciences and meteorology, it is in a relatively early stage in atmospheric composition. In this Union Symposium, we plan to highlight the need for, and to illustrate exciting advances in the translation of atmospheric composition research to support services. We will build upon work within the World Meteorological Organization and other communities related to the closer linkages of weather, atmospheric composition, and climate research and related services. We will also articulate the needs for advances in observing systems, models and a better understanding of fundamental processes. This session will also serve as a celebration of the 30 year anniversary of the WMO Global Atmosphere Watch programme and an opportunity for the broader community to envision partnerships needed to facilitate the effective translation of atmospheric composition research.

In October 2018, the IPCC published its special report on impacts of global warming of 1.5 deg C. Another recent, highly publicised study suggests that the planet could pass an irreversible threshold into a so called “Hothouse Earth” state for a temperature increase of as low as 2 degrees C above pre-industrial temperatures, while other studies and commentaries have emphasised the urgency on climate action, arguing that 2020 must be a turning point for global fossil fuel emissions, to increase the chance of maintaining a safe operating space for the humans on the planet. In 2018, the IPCC celebrated its 30th anniversary. The importance of taking action on human-induced climate change has been emphasised with governments around the world since the 1990s yet CO2 concentrations continue to rise and international initiatives have, to date, had limited and insufficient impact to avert some of the most serious consequences of climate change.
How close are we to one or more critical thresholds (cliff edge)? Is there time to avert passing one or more of these thresholds? What can the geoscience community do to reduce the risks? How important is bottom up versus top down action to ensuring the least worst outcome? These are some of the questions we will debate with world experts in their field and authors of the thought papers on these topics.

The geosciences are currently used by policymakers in a wide variety of areas to help guide the decision-making process and ensure that the best possible outcome is achieved. While the importance of scientific advice and the use of evidence in the policymaking process is generally acknowledged by both policymakers and scientists, how scientific advice is integrated and who is responsible is still unclear.

EU Policymakers frequently highlight institutionalised processes for integrating scientific advice into policy such as European Commission's Group of Chief Scientific Advisors (SAM) and the EU Commission’s Register of Expert Groups. But how efficient and accessible are these mechanisms really?

Some emphasise the need for scientists to have their own policy networks in place so that they can share their research outcomes with policymakers who can then use it directly or pass it on to those responsible for relevant legislation. But from funding applications to teaching and even outreach activities – scientists are often already overloaded with additional tasks on top of their own research. Can they really be held responsible for keeping up with the latest policy news and maintaining a constantly changing network of policymakers as well?

This debate will feature a mixed panel of policymakers and geoscientists who have previously given scientific advice. Some key questions that the panel will debate include:
• How can the accessibility of current EU science-advisory mechanisms be improved?
• Are scientists doing enough to share their research?
• And who is responsible for ensuring that quality scientific evidence is used in policymaking?

Speakers will be encouraged to explain any science advisory mechanism that they highlight (e.g. SAM) to ensure that the debate is understood by all those in attendance.

While the panel and subsequent debate will have an EU focus, it is likely that many of the issues discussed will be applicable to countries around the world.

The ever more challenging work environments and increasing pressures on Early Career Scientists e.g. publish or perish, securing grant proposals, developing transferable skills and many more – and all while having a lack of job security. This puts a big strain on Early Career Scientists and this can lead to neglected mental well-being which in turn increases the risk of developing anxiety, depression or other mental health issues. The graduate survey from 2017 (https://www.nature.com/nature/journal/v550/n7677/full/nj7677-549a.html) shows that 12% of respondents had sought help or advice for anxiety or depression during their PhD.

In this debate we want to discuss: Is there a problem? How ECS can take control of their mental wellbeing and prioritise this in the current research environment? And what support would ECS like to see from organisations like EGU or their employers?

"What counts may not be countable and what is countable may not count". Assessments of scientists and their institutions tend to focus on easy-to-measure metrics related to research outputs such as publications, citations, and grants. However, society is increasingly dependent on Earth science research and data for immediate decisions and long-term planning. There is a growing need for scientists to communicate, engage, and work directly with the public and policy makers, and practice open scholarship, especially regarding data and software. Improving the reward and recognition structure to encourage broader participation of scientists in these activities must involve societies, institutions, and funders. EGU, AGU, and JPGU have all taken steps to improve this recognition, from developing new awards to starting journals around the topic of engaging the public to implementing FAIR data practices in the Earth, environmental, and space sciences, but far more is needed for a broad cultural change. How can we fairly value and credit harder-to-measure, these less tangible contributions, compared to the favoured metrics? And how can we shift the emphasis away from the "audit culture" towards measuring performance and excellence? This session will present a distinguished panel of stakeholders discussing how to implement and institutionalize these changes.

Wed, 10 Apr, 12:45-14:00 / Room E1

Plastic pollution is recognized as one of the most serious and urgent problems facing our planet. Rates of manufacture, use and ultimately disposal of plastics continue to soar, posing an enormous threat to the planet’s oceans and rivers and the flora and fauna they support. There is an urgent need for global action, backed by sound scientific understanding, to tackle this problem.

This Union Symposium will address the problems posed to our planet by plastic pollution, and examine options for dealing with the threat.

The Games Night is a space to gather, socialise, and play some games. The catch is that all the games are based on Geoscience! Bring along your own games or try one of the others in the session and meet the people who created them. This will also be your chance to try games featured in the Games for Geoscience session.

Join us to help put some of the world's most vulnerable places on the map. A mapathon is a mapping marathon, where we get together to contribute to OpenStreetMap - the world's free map.
No experience is necessary - just bring your laptop and we will provide the training. Learn more about crowdsourcing, open data and humanitarian response - we will also provide some tips for how to host a mapathon at your home institution.

Plastic Oceans UK have been experts on plastic pollution for nearly a decade - solving the plastic crisis through their science, sustainability and education programmes. This all began with the award-winning documentary A Plastic Ocean, now available for streaming on Netflix.

Through changing attitudes, behaviours and practices on the use and value of plastics, we can stop plastic pollution reaching the ocean within a generation.

Come along to the screening of A Plastic Ocean to understand the impacts of plastic pollution around the world, what action we can take to stop plastics entering our natural world and pose your questions to the film's producer, Jo Ruxton, at the end of film.

http://plasticoceans.uk/