Tsunami (NH Division Outstanding ECS Lecture by Jadranka Šepić) (co-sponsored by JpGU)
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.
Extreme events in sea waves: physical mechanisms and mathematical models
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.
Marine Geological Processes in Past, Present, and Future
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.
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/
Extreme Internal Wave Events: Generation, Transformation, Breaking and Interaction with the Bottom Topography
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.
Natural hazards and climate change impacts in coastal areas
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.
Oceanography at coastal scales. Modelling, coupling and observations.
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.
Surface Waves and Wave-Coupled Effects in Lower Atmosphere and Upper Ocean
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.
Gas hydrates in marine sediments: a potential resource and its influences on slope stability
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.
Achievements and perspectives in scientific ocean and continental drilling
Scientific drilling through the International Ocean Discovery Program (IODP) and the International Continental Scientific Drilling Program (ICDP) continues to provide unique opportunities to investigate the workings of the interior of our planet, Earth’s cycles, natural hazards and the distribution of subsurface microbial life. The past and current scientific drilling programs have brought major advances in many multidisciplinary fields of socio-economic relevance, such as climate and ecosystem evolution, palaeoceanography, the deep biosphere, deep crustal and tectonic processes, geodynamics and geohazards. This session invites contributions that present and/or review recent scientific results from deep Earth sampling and monitoring through ocean and continental drilling projects. Furthermore, we encourage contributions that outline perspectives and visions for future drilling projects, in particular projects using a multi-platform approach.
Marine Pollution Assessment, Predictions and Risk Mapping
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)?
Coastal zones under natural and human-induced pressure (sponsored by CCS - IGU)
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).
Climate and other drivers of change: Interlinkages, ramifications and impacts in coastal regions
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.