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.

Biological and ecological experimental studies in laboratory and nature, and their applications to the paleo- and future understanding of marine environments

In order to discuss Earth marine realms and answer questions about biotic evolution and ecosystem functioning in the Past, Present and Future, scientists try to take various laboratory- or natural-based experimental approaches. This includes experiments controlling environmental variables, experiments with stable or radioactive isotopic biomarkers, breeding experiments, genetic analyses (e.g. ancient DNA), or so-called natural laboratories (e.g. the Lessepsian invasion via the Suez Canal or natural CO2 vents functioning as ocean acidification analogues). Altogether, they unriddle faunal and ecosystem functional responses to changing connectivity patterns, habitat change or global change threats. These experimental approaches are effective to make clear how biotic evolution takes place in nature, how ecosystems also act as functional labs and how Earth systems have moved and can move dynamically. They enable us to make more robust projections into the future or decipher past ecosystem trajectories with potential analogues to future change. In this session we welcome contributions that use experimental approaches in this context, but also discussing biogeochemical proxies that fix information of past environmental change during biomineralization in calcareous or siliceous tests.

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.

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.

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.

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.

Biota affect hydrology, sediment transport, weathering and soil formation over variable temporal and spatial scales and thereby influence, hillslope, fluvial, coastal, and aeolian landscape form and dynamics. In turn, geomorphological and hydrological processes have large impacts on ecological processes by shaping topography and affecting water availability, which determines biological diversity and succession. Despite some advances, the conceptualisation and quantification of the processes, rates and feedbacks between geomorphology, hydrology and ecology are still limited.

Understanding these feedbacks between biological, hydrological and geomorphological processes is becoming increasingly important as new ‘building with nature’ projects emerge and also increasingly find their way into management (i.e. restoration projects). Physical, chemical and biological processes are in a constant state of flux, vary across both temporal and spatial scales and are regulated or enhanced by anthropogenic activities. Understanding of the biogeomorphological and ecohydrological effects of anthropogenic activities/ approaches and their wider socio-economic implications, remains largely rudimentary particularly in systems that are sensitive to human-induced or natural environmental change (e.g. high-mountain and polar environments, deserts, hillslopes, rivers and wetlands, salt marshes and deltas). As a result, there is a need to develop understanding around i) the magnitude and temporal persistence of anthropogenic stressors and their effects, ii) ecosystem resilience to anthropogenic stressors (including critical transitions in ecosystem state), and iii) new sustainable approaches to catchment management, such as utilization of ecosystem engineers for habitat improvements.

This session seeks contributions that are investigating biogeomorphologic interactions across all spatial and temporal scales, including experimental, field and computational/numerical modelling studies. We especially encourage interdisciplinary studies on river, and delta biogeomorphology, animal influences on geomorphic processes, chronologies of biogeomorphological change, and hillslope processes. Emphasis will be given to novel research on biogeomorphological feedbacks, on the quantification of feedbacks and associated rates, the linkage between terrestrial and aquatic environments, and the investigation of the resilience of coupled eco-hydro-geomorphic systems to human impact and climate change.

Public information:
We are happy to have two keynote speakers this year, one for fluvial biogeomorphology with Borbála Hortobágyi presenting on riparian plant response and effect traits on alluvial bars and one for coastal biogeomorphology with Olivier Gourgue presenting a new bio-geomorphic model approach accounting for subgrid-scale heterogeneity of biogenic structures.

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

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 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.