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.

Public information:
The release of radioactive materials by human activity (such as nuclear accidents) are both severe hazard problem as well as ideal markers in understanding geoscience at all level of the Earth because it cycles through atmosphere, soil, plant, water system, ocean, and lives. Therefore, we must gather knowledge from all geoscience field for comprehensive understanding.

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.