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.

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'.

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.

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.

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.

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/

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).