Today, it is almost certain that global climate change will affect the frequency and severity of extreme meteorological and hydrological events. It is necessary to develop models and methodologies for the better understanding, forecasting, hazard prevention of weather induced extreme events and assessment of disaster risk. This session considers extreme events that lead to disastrous hazards induced by severe weather and climate change. These can, e.g., be tropical or extratropical rain- and wind-storms, hail, tornadoes or lightning events, but also floods, long-lasting periods of drought, periods of extremely high or of extremely low temperatures, etc. Papers are sought which contribute to the understanding of their occurrence (conditions and meteorological development), to assessment of their risk and their future changes, to the ability of models to reproduce them and methods to forecast them or produce early warnings, to proactive planning focusing to damage prevention and damage reduction. Papers are also encouraged that look at complex extreme events produced by combinations of factors that are not extreme by themselves. The session serves as a forum for the interdisciplinary exchange of research approaches and results, involving meteorology, hydrology, hazard management and/or applications like insurance issues.

Lightning is the energetic manifestation of electrical breakdown, occurring after charge separation processes operating on micro and macro-scales, leading to strong electric fields within thunderstorms. Lightning is associated with severe weather, torrential rains and flash floods. It has significant effects on various atmospheric layers and drives the fair-weather electric field. It is a strong indicator of convective processes on regional and global scales, potentially associated with climate change. Thunderstorms and lightning are also associated to the production of energetic radiation up to tens of MeV on time scales from sub-millisecond (Terrestrial Gamma-ray Flashes) to tens of seconds (gamma-ray glows).

This session seeks contributions from research in atmospheric electricity on:

Atmospheric electricity in fair weather and the global electrical circuit
Atmospheric chemical effects of lightning and LtNOx
Middle atmospheric Transient Luminous Events
Energetic radiation from thunderstorms and lightning.
Remote sensing of lightning from space and by lightning detection networks
Results from the Atmosphere-Space Interaction Monitor (ASIM) mission.
Thunderstorms, flash floods and severe weather
Lightning and climate
Modeling of thunderstorms and lightning
Now-casting and forecasting of thunderstorms
New airborne and ground-based observation techniques

High-impact climate and weather events typically result from the interaction of multiple hazards across various spatial and temporal scales. These events, also known as Compound Events, often cause more severe socio-economic impacts than single-hazard events, rendering traditional univariate extreme event analyses and risk assessment techniques insufficient. It is therefore crucial to develop new methodologies that account for the possible interaction of multiple physical drivers when analysing high-impact events. Such an endeavour requires (i) a deeper understanding of the interplay of mechanisms causing Compound Events and (ii) an evaluation of the performance of climate/weather, statistical and impact models in representing Compound Events.
The European COST Action DAMOCLES together with the EU H2020 ANYWHERE project will coordinate these efforts by building a research network consisting of climate scientists, impact modellers, statisticians, and stakeholders. This session creates a platform for this network and acts as an introduction of the work related to DAMOCLES and ANYWHERE to the research community. We therefore invite papers studying Compound Events and addressing the following topics representing the five working groups of DAMOCLES and Work Package 2 of ANYWHERE working on multi-hazard impacts..

Synthesis and Analysis: What are common features for different classes of Compound Events? Which climate variables need to be assessed jointly in order to address related impacts? How much is currently known about the dependence between these variables?
Stakeholders and science-user interface: Which events are most relevant for stakeholders? What are novel approaches to ensure continuous stakeholder engagement?
Impacts: What are the currently available sources of impact data? How can they be used to link observed impacts to climate and weather events?
Statistical approaches, model development and evaluation: What are possible novel statistical models that could be applied in the assessment of Compound Events?
Realistic model simulations of events: What are the physical mechanisms behind different types of Compound Events? What type of interactions result in the joint impact of the hazards that are involved in the event? How do these interactions influence risk assessment analyses?

Karst environments are characterized by distinctive landforms and unique hydrologic behaviors. Karst systems are commonly extremely complex, heterogeneous, and very difficult to manage because their formation and evolution are controlled by a wide range of geological, hydrological, geochemical and biological processes. Further, karst systems are extremely vulnerable due to the direct connection between the surface and subsurface compartments through conduit networks.
The great variability and unique connectivity may result in serious engineering problems: on one hand, karst groundwater resources are readily contaminated by pollution because of the rapidity of conduit flow; on the other hand, the presence of karst conduits that weakens the strength of the rock mass may lead to serious natural and human-induced hazards. The plan and development of engineering projects in karst environments thus require: 1) an enhanced understanding of natural processes that govern the initiation and evolution of karst systems through both field and modelling approaches, and 2) specific interdisciplinary approaches aiming at at better assessing the associated uncertainties and minimizing the detrimental effects of hazardous processes and environmental problems.
This session calls for abstracts on research related to geomorphology, hydrogeology, engineering geology, and/or hazard mitigation in karst environments in the context of climate change and increased human disturbance. It also aims to discuss various characterization and modelling methods applied in each specific research domain, with their consequences on the understanding of the whole process of karst genesis and functioning.

Flooding is the foremost natural hazard around the world, affecting human life and property (directly and indirectly). In the current era, many hydraulic and hydrologic modelling techniques are available for flood risk assessment and management as well as flood risk prevention and preparedness. They provide a platform for the scientific community to explore the causes of floods and to build up efficient methods for flood mitigation.

This session invites in-depth research work carried out through flood modelling including hydrological modelling, flood hydrodynamic modelling, flood inundation mapping, flood hazard mapping, risk assessment, flood policy, and flood mitigation strategy. It also welcomes studies dealing with various uncertainties associated with different stages of modelling and the exploration of modern techniques for model calibration and validation.

In addition, real-time flood inundation mapping is an important aspect for the evacuation of people from low-lying areas and reduction of the death toll. Real-time data gained through UAV-based flood inundation mapping and associated uncertainty in real-time aerial surveying are welcome in this special issue.

Invited Speaker:
PD Dr. Heidi Kreibich (Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences)
Head of the Working Group Flood risk and climate adaptation

Prediction skill of hydro-meteorological forecasting systems has remarkably improved in recent decades. Advances in both weather and hydrology models, linked to the availability of more powerful and efficient computational resources, allowed the development of even more complex systems based on the combination of spatially distributed physically-based hydrologic- and hydraulic models with deterministic and/or ensemble meteorological forecasting systems. Coupled atmosphere-hydrological modeling aims at describing the full atmospheric-terrestrial regional water cycle, i.e. extending from the top of the atmosphere, through the boundary layer, via the land surface and subsurface till lateral flow in the groundwater and in the river beds. Fully two-way coupled model systems thereby give the possibility to study long range feedbacks between groundwater, soil moisture redistribution and precipitation. Via improved and completed process descriptions fully coupled modeling may also increase the performance of hydrometeorological predictions of various spatial and temporal scales.
The objective of the session is to create a valuable opportunity for the interdisciplinary exchange of ideas and experiences among atmospheric-hydrological modelers and members of both hydrology- and Earth System modeling communities. Contributions are invited dealing with the complex interactions between surface water, groundwater and regional climate, with a specific focus on those presenting work on the development or application of one-way (both deterministic and ensemble) or fully-coupled hydrometeorological prediction systems for floods/flash-floods, droughts and water resources. Presentations of inter-comparisons between one-way and fully-coupled hydrometeorological chains are encouraged, such as contributions on novel one-way and fully-coupled modeling systems that bridge spatial scales through dynamic regridding or upscaling/downscaling methodologies. Also, presentations addressing data assimilation in coupled model systems are welcome. Likewise abstracts are invited on field experiments and testbeds equipped with complex sensors and measurement systems allowing multi-variable validation of such complex modeling systems.

Heat extremes are already one of the deadliest meteorological events and they are projected to increase in intensity and frequency due to rising CO2 emissions. Thus the risk these events pose to society may increase dramatically and society will need to adapt if the worst impacts are to be avoided. However, uncertainties for understanding the development of extreme heat episodes and their impacts remain large. This session therefore aims to address this challenge, welcoming research which improves our understanding of extreme heat events and how to respond to them. Suitable contributions in this regard may: (i) assess the drivers and underlying processes of extreme heat in observations and models; (ii) explore the diverse socio-economic impacts of extreme heat events (for example, on aspects relating to human health or economic productivity); (iii) address forecasting of extreme heat at seasonal to sub-seasonal time scales; (iv) focus on societal adaptation to extreme heat, including (but not limited to) the implementation of Heat-Health Early Warning Systems.

Predicting current and future flood risk continues to be a major challenge for climatologists, hydrologists and hydraulicians. The complex nature of flood risk challenges established risk assessment methodologies and their modelling components, such as hydrologic and hydraulic simulation. Further, flood risk predictions are characterised by considerable uncertainty, which needs to be evaluated and clearly communicated to decision-makers. This session aims to review state-of-the-art flood risk assessment methodologies on different scales and experiences of recent flood events, the physical processes occurring during flood flows and uncertainties in measurement data and modelling. We welcome submissions in the areas of flood plain risk assessment and uncertainty analysis, floodplain management including new approaches to hydraulic and hydrologic modelling, model calibration and validation. Also, we are interested in contributions that show what kind of information is particularly helpful for reducing uncertainty, as well as measures for flood mitigation and the cost effectiveness of these measures. Since flood risk analyses have to include statements on extreme events, observation data are scarce. Therefore, we particularly invite contributions that address the issue of validation of flood risk analyses.

Globally, we are facing massive challenges on how we manage our catchments, in both rural and urban areas, in the next decades. With a changing climate and increased pressure on our land resources we need to ensure we manage the water in our catchments more sustainably and even more so during hydro-climatic extremes. Nature-based solutions (NBS) are 'living' solutions inspired by and continuously supported by nature or natural processes. NBSs are designed to address various societal challenges in a resource efficient and adaptable manner to provide simultaneously economic, social and environmental benefits (European Commission 2015). Therefore NBS can be used within both rural and urban areas to mitigate catchment flood risk, provide drought resilience, protect and enhance endangered freshwater ecosystems and reduce diffuse pollution. However, there are still challenges in implementing NBS for reasons such as lack of evidence surrounding the effectiveness (e.g. at larger scales) and for delivering multiple benefits.

Therefore this session focuses on key research and policy questions associated with NBS. For example, how do we develop locally adapted solutions in catchments and urban areas? What are the impacts of these measures at larger scales (e.g. sub-catchment/ catchment scale)? How can we address multi-disciplinary benefits? How can we do more for less? Importantly, how can we provide the evidence base around the concept of Nature Based Solutions for managing hydrological extremes and water resource management? Examples of studies that cover either the management of flooding, drought, water quality or ecology (both in the rural, peri-urban and urban context) using NBS approaches are at the heart of this session. Management measures could include techniques such as Green Infrastructure, Natural Water Retention Measures, Natural Flood Management, Catchment Restoration, Ecological Engineering or Blue-Green Infrastructure. We invite (but not limit to) abstracts that demonstrate good quality hydrological experiments around NBS; that develop new or improve existing modelling approaches/decision support tools; that investigate and quantify the multiple benefits; and which explore the challenges of implementation (e.g. stakeholder uptake/economics/cost benefit).

Geodesy is becoming increasingly important for observing the hydrological cycle and its effects on solid Earth shape. Signals in geodetic data have revealed water's influence on other geophysical processes including earthquakes, volcanos, land subsidence, mountain uplift, and other aspects of long- and short-term vertical land motion. GPS and InSAR measurements, for example, respectively provide high temporal and spatial resolution to study natural hydrologically-related deformation and monitor anthropogenic groundwater extraction and recharge, and GRACE is helping to track changes in the global terrestrial water storage. Signals of loading from changes in surface and groundwater storage are seen from basin to continental scale. Additionally, novel use of GPS reflectometry is operational for monitoring soil moisture and snow depth at continuous GPS stations in the western USA and Canada. We encourage contributions describing new observations and models of hydrological signals in geodetic time series and/or imaging. These include but are not limited to studies exploring deformation induced by loading, aquifer extraction/recharge, poroelastic deformation and stress changes, techniques for removing hydrological signals from geodetic datasets, monitoring water resources, or teleconnections between hydrologic and other geophysical phenomena.

Fluvial systems cover much of the Earth’s surface; they convey water, sediments, and essential nutrients from the uplands to the sea, intermittently transferring these materials from the river channel to the adjacent floodplain. The routing of sediment and water through the channel network initiates complex process-form interactions as the river bed and banks adjust to changes in flow conditions. Despite their ubiquity, little is known about the landform-driven morphodynamic interactions taking place within the channel that ultimately determine patterns of sedimentation and changes of channel form. Furthermore, an understanding of how these process-form interactions scale with the size of the fluvial system is also currently lacking. Recent technological advances now afford us the opportunity to study and to quantify these process-form interactions in detail across a range of spatial and temporal scales. This session aims to bring together interdisciplinary researchers working across field, experimental, and numerical modelling approaches who are advancing methods and providing new insights into: (i) sediment transport and morphodynamic functioning of fluvial systems, (ii) evaluating morphological change at variable spatial and temporal scales, such as at event vs. seasonal scales, and (iii) investigating the sedimentology of these river systems. We particularly welcome applications which investigate the morphodynamic response of fluvial systems in all types and sizes and we specifically would like to encourage submissions from early career researchers and students.

Invited speakers:
- Lina Polvi Sjöberg (Umeå University): "Streams frozen in time? Particle- to catchment- scale dynamics of high-latitude post-glacial streams."
- Anette Eltner (TU Dresden): "Unmanned aerial and water vehicle data for hydro-morphological river
monitoring"

The understanding of tropical phenomena and their representation in numerical models still raise important scientific and technical questions, particularly in the coupling between the dynamics and diabatic processes. Among these phenomena, tropical cyclones (TC) are of critical interest because of their societal impacts and because of uncertainties in how their characteristics (cyclogenesis processes, occurrence, intensity, latitudinal extension, translation speed) will change in the framework of global climate change. The monitoring of TCs, their forecasts at short to medium ranges, and the prediction of TC activity at extended range (15-30 days) and seasonal range are also of great societal interest.

The aim of the session is to promote discussions between scientists focusing on the physics and dynamics of tropical phenomena. This session is thus open to contributions on all aspects of tropical meteorology between the convective and planetary scale, such as:

- Tropical cyclones,
- Convective organisation,
- Diurnal variations,
- Local circulations (i.e. island, see-breeze, etc.),
- Monsoon depressions,
- Equatorial waves and other synoptic waves (African easterly waves, etc.),
- The Madden-Julian oscillation,
- etc.

We especially encourage contributions of observational analyses and modelling studies of tropical cyclones and other synoptic-scale tropical disturbances including the physics and dynamics of their formation, structure, and intensity, and mechanisms of variability of these disturbances on intraseasonal to interannual and climate time scales.

Findings from recent field campaigns such as YMC and PISTON are also encouraged.

Numerical atmospheric dispersion models are an essential tool for assessment of emergency situations related to airborne particles or gases released into the atmosphere by natural or man-made hazards. They are used complementary to observational data in order to fill-in e.g. temporal- or spatial gaps and to conduct forecasts facilitating the planning of mitigation strategies.
The focus of this session will be on environmental emergency scenarios (airborne hazards) which can have extremely high impact on society and environment: volcano eruptions, nuclear accidents, as well as more localised emergencies, such as dust storms and strong vegetation fires or other occasions when hazardous pollutants are injected into the atmosphere.

The International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) senses the solid Earth, the oceans and the atmosphere with a global network of seismic, infrasound, and hydroacoustic sensors as well as detectors for atmospheric radioactivity. The primary purpose of the IMS data is for nuclear explosion monitoring regarding all aspects of detecting, locating and characterizing nuclear explosions and their radioactivity releases. On-site verification technologies apply similar methods on smaller scales as well as geophysical methods such as ground penetrating radar and geomagnetic surveying with the goal of identifying evidence for a nuclear explosion close to ground zero. Papers in this session address advances in the sensor technologies, new and historic data, data collection, data processing and analysis methods and algorithms, uncertainty analysis, machine learning and data mining, experiments and simulations including atmospheric transport modelling. This session also welcomes papers on applications of the IMS and OSI instrumentation data. This covers the use of IMS data for disaster risk reduction such as tsunami early warning, earthquake hazard assessment, volcano ash plume warning, radiological emergencies and climate change related monitoring. The scientific applications of IMS data establish another large range of topics, including acoustic wave propagation in the Earth crust, stratospheric wind fields and gravity waves, global atmospheric circulation patterns, deep ocean temperature profiles and whale migration. The use of IMS data for such purposes returns a benefit with regard to calibration, data analysis methods and performance of the primary mission of monitoring for nuclear explosions.

As the societal impacts of hazardous weather and other environmental pressures grow, the need for integrated predictions which can represent the numerous feedbacks and linkages between physical and chemical atmospheric processes is greater than ever. This has led to development of a new generation of high resolution multi-scale coupled prediction tools to represent the two-way interactions between aerosols, chemical composition, meteorological processes such as radiation and cloud microphysics.

Contributions are invited on different aspects of integrated model and data assimilation development, evaluation and understanding. A number of application areas of new integrated modelling developments are expected to be considered, including:

i) improved numerical weather prediction and chemical weather forecasting with feedbacks between aerosols, chemistry and meteorology,

ii) two-way interactions between atmospheric composition and climate variability.

This session aims to share experience and best practice in integrated prediction, including:

a) strategy and framework for online integrated meteorology-chemistry modelling;
b) progress on design and development of seamless coupled prediction systems;
c) improved parameterisation of weather-composition feedbacks;
d) data assimilation developments;
e) evaluation, validation, and applications of integrated systems.

This Section is organised in cooperation with the Copernicus Atmosphere Monitoring Service (CAMS), the "Pan-Eurasian Experiment" (PEEX) multidisciplinary program and the WMO Global Atmosphere Watch (GAW) Programme, celebrating its 30 years anniversary in 2019.

Precipitation is the main driver for a number of hydrologic and geomorphic hazards (such as floods, landslides and debris flows), which pose a significant threat to modern societies on a global scale. The continuous increase of population and urban settlements in hazard-prone areas in combination with evidence of changes in precipitation patterns lead to a continuous increase of the risk associated with precipitation-induced hazards. To improve resilience and to design more effective mitigation strategies, we need to better understand the aspects of vulnerability, risk, and triggers that are associated with these hazards.

This session aims to gather contributions dealing with various precipitation induced hazards that address the aspects of vulnerability analysis, risk estimation, impact assessment, mitigation policies and communication strategies. Specifically, we aim to collect contributions from the academia, the industry (e.g. insurance) and government agencies (e.g. civil protection) that will help identify the latest developments and ways forward for improving the resilience of communities at local, regional and national scales, and proposals for improving the interaction between different entities and sciences.

Contributions focusing on, but not limited to, novel developments and findings on the following topics are particularly encouraged:

- Physical and social vulnerability analysis and impact assessment of precipitation-related hazards.
- Advances in the estimation of socioeconomic risk from precipitation-induced hazards.
- Characteristics of precipitation patterns leading to high-impact events.
- Evidence on the relationship between precipitation patterns and socioeconomic impacts.
- Hazard mitigation procedures.
- Communication strategies for increasing public awareness, preparedness, and self-protective response.
- Impact-based forecast and warning systems

Hydroclimatic conditions and the availability of water resources in space and time constitute important factors for maintaining an adequate food supply, the quality of the environment, and the welfare of inhabitants, in the context of sustainable growth and economic development. This session is designed to explore the impacts of hydroclimatic variability, climate change, and the temporal and spatial availability of water resources on: food production, population health, the quality of the environment, and the welfare of local ecosystems. We particularly welcome submissions on the following topics:

Complex inter-linkages between hydroclimatic conditions, food production, and population health, including: extreme weather events, surface and subsurface water resources, surface temperatures, and their impacts on food security, livelihoods, and water- and food-borne illnesses in urban and rural environments.

Quantitative assessment of surface-water and groundwater resources, and their contribution to agricultural system and ecosystem statuses.

Spatiotemporal modeling of the availability of water resources, flooding, droughts, and climate change, in the context of water quality and usage for food production, agricultural irrigation, and health impacts over a wide range of spatiotemporal scales

Intelligent infrastructure for water usage, irrigation, environmental and ecological health monitoring, such as development of advanced sensors, remote sensing, data collection, and associated modeling approaches.

Modelling tools for organizing integrated solutions for water, precision agriculture, ecosystem health monitoring, and characterization of environmental conditions.

Water re-allocation and treatment for agricultural, environmental, and health related purposes.

Impact assessment of water-related natural disasters, and anthropogenic forcings (e.g. inappropriate agricultural practices, and land usage) on the natural environment; e.g. health impacts from water and air, fragmentation of habitats, etc.

The assessment of precipitation variability and uncertainty is crucial in a variety of applications, such as flood risk forecasting, water resource assessments, evaluation of the hydrological impacts of climate change, determination of design floods, and hydrological modelling in general. Within this framework, this session aims to gather contributions on research, advanced applications, and future needs in the understanding and modelling of precipitation variability, and its sources of uncertainty.
Specifically, contributions focusing on one or more of the following issues are particularly welcome:
- Novel studies aimed at the assessment and representation of different sources of uncertainty versus natural variability of precipitation.
- Methods to account for different accuracy in precipitation time series, e.g. due to change and improvement of observation networks.
- Uncertainty and variability in spatially and temporally heterogeneous multi-source precipitation products.
- Estimation of precipitation variability and uncertainty at ungauged sites.
- Precipitation data assimilation.
- Process conceptualization and modelling approaches at different spatial and temporal scales, including model parameter identification and calibration, and sensitivity analyses to parameterization and scales of process representation.
- Modelling approaches based on ensemble simulations and methods for synthetic representation of precipitation variability and uncertainty.
- Scaling and scale invariance properties of precipitation fields in space and/or in time.
- Physically and statistically based approaches to downscale information from meteorological and climate models to spatial and temporal scales useful for hydrological modelling and applications.

Over the last decades, a significant body of empirical and theoretical work has revealed the departure of statistical properties of hydrometeorological processes from the classical statistical prototype, as well as the scaling behaviour of their variables in general, and extremes in particular, in either state, space and/or time. This PICO session (i.e., a 2-minute oral presentation, nicknamed "2-minute madness", followed by an interactive poster presentation on dedicated touch-screens) aims at presenting the latest developments on:
- Coupling stochastic approaches with deterministic hydrometeorological predictions, in order to better represent predictive uncertainty;
- Stochastic-dynamic approaches that are more consistent with the hydrometeorological reality than both deterministic and statistical models separately;
- Variability at climatic scales and its interplay with the ergodicity of space-time probabilities;
- Linking underlying physics and scaling stochastics of hydrometeorological extremes;
- Development of parsimonious representations of probability distributions of hydrometeorological extremes over a wide range of scales and states;
- Understanding and using parsimonious parametrizations of extremes in risk analysis applications and hazard prediction.
The suggested session description is submitted to the HS division of EGU and is sponsored by the International Commission on Statistical Hydrology of the International Association of Hydrological Sciences (ICSH-IAHS, former STAHY).

Urban hydrological processes are characterised by high spatial variability and short response times resulting from a high degree of imperviousness. Therefore, urban catchments are especially sensitive to space-time variability of precipitation at small scales. High resolution precipitation measurements in cities are crucial to properly describe and analyse urban hydrological response. At the same time, urban landscapes pose specific challenges to obtaining representative precipitation and hydrological observations.
This session focuses on high resolution precipitation and hydrological measurements in cities and on approaches to improve modelling of urban hydrological response:
- Novel techniques for high resolution precipitation measurement in cities and approaches for merging remote sensing data with in situ measurements to obtain representation of urban precipitation fields;
- Novel approaches to hydrological field measurements in cities, including data obtained from citizen observatories;
- Novel approaches to modelling urban catchment properties and hydrological response, from physics-based models, fully and semi-distributed modelling to stochastic and statistical conceptualisation;
- Applications of measured precipitation fields in urban hydrological models to improve prediction of flood response and real-time control of stormwater systems for pollution load reduction;
- rainfall modelling for urban applications, including stochastic rainfall generators.

Extreme convective events are increasing in northern and eastern Europe in frequency and intensity causing many deaths, injuries and damage to property every year, and accounting for major economic damages related to natural disasters in several countries. Atlantic hurricanes become extra-tropical cyclones and, sometimes, reach northern Europe. Mediterranean hurricanes (Medicanes or tropical-like cyclones) are not that frequent as other convective systems or tropical cyclones, but these can still reach the intensity of tropical cyclones, causing severe damages in the Southern European region. Supercells and connected tornadoes are also becoming more frequent in central Europe.

In recent years, attention was paid to the detection and monitoring of volcanic ash clouds as their impact on the European air traffic control system was unprecedented. In 2010 the Eyjafjallajökull eruption caused the closure of the airspace of several countries generating the largest air traffic shutdown since the World War II. Volcanic clouds are very dangerous for the aviation operations as they can cause damage of the aircraft systems and engines not only close to active volcanoes but also at large distance from the eruption, and they affect economic, political and cultural activities. Europe is located between the chain of Icelandic and Italian/African volcanoes which are unpredictable, and could easily emanate the ash clouds throughout the skies of the continent.

The recent Anak Krakatau eruption (December 2018) highlighted the issue on different techniques to distinguish volcanic ash clouds than convective clouds and the unsolved problem to understand if the cloud top was tropospheric or stratospheric. Specific discussion on this topic will be very welcome to the session.

The extreme convective clouds and the volcanic ash clouds are types of “extreme clouds”. The “extreme clouds” detection and estimation of their physical parameters is a highly multidisciplinary and challenging topic since the same techniques and instruments can be used for meteorology, volcanic monitoring, atmospheric physics and climate purposes. But there is an urgent need to develop new techniques and instruments for monitoring, detecting and modeling “extreme clouds” to develop early warning systems and to support users, decision makers and policy makers. Given the large uncertainties that still remain in the field, enlarging and coordinating the research community for developing new techniques and improving our knowledge is required. Furthermore, there is a need for improved information exchange regarding the impact of the extreme clouds on daily operations between the producers and intended uses of the information.

The objective of the session is to connect different communities in touch with the “extreme clouds”, such as scientists working in remote sensing, modelers, meteorologists, physicists, aviation managers. Thus, allowing the researchers to understand the end-users’ needs and for the end-users to understand the research capabilities.

This session solicits the latest studies from the spectrum of:
- detection, monitoring and modeling of extreme clouds,
- understanding the impact of extreme clouds on climate changes,
- proposal of new products or services focused on the end-users prospective,
- discussion on Anak Krakatau eruption (December 2018)

By considering studies over this range of topics we aim to identify new methods, detail current challenges, understand common techniques/methods and identify common discussions within the communities of atmospheric physicists, meteorologists, modelers, air traffic managers, pilots sensors engineers and engines manufacturers. We particularly welcome and encourage contributions connecting different fields such as:
- forecasting tools to support air traffic management improving the limits of the present science and new products/tools providing better services to the end-users,
- extreme clouds remote sensing with novel techniques and new sensors,
- novel techniques to detect overshooting and their impact on climate.

The aim of the session is to promote discussions between scientists on future developments, in understanding, monitoring and forecasting the extreme clouds, studying their impact and to extend the discussion with the end-users for improving air safety. This session is thus open to contributions on all aspects of remote sensing, forecast, and tools/services development such as:

- Extreme clouds remote sensing
- Extreme clouds modeling
- Extreme clouds forecasting and nowcasting
- Extreme clouds structure
- Extreme clouds and climate change
- Overshooting and Ice clouds
- Air traffic management issues related to extreme clouds
- Airport issues

The occurrence of extremes such as droughts, flash floods, hailstorms, storm surges and tropical storms can have significant and sometimes catastrophic consequences to society. However, not all low probability weather/climate events will lead to “high impacts” on human or natural systems or infrastructure. Rather, the severity of such events depend also intrinsically on the exposure, vulnerability and/or resilience to such hazards of affected systems, including emergency management procedures. Similarly, high impact events may be compounded by the interaction of several, e.g., in their own right less severe hydro-meteorological incidents, sometimes separated in time and space. Or they may similarly result from the joint failures of multiple human or natural systems. Consequently, it is a deep transdisciplinary challenge to learn from past high impact events, understand the mechanisms behind them and ultimately to project how they may potentially change in a future climate.

The ECRA (European Climate Research Alliance) Collaborative Programme on “High Impact Events and Climate Change” aims to promote research on the mechanisms behind high impact events and climate extremes, simulation of high impact events under present and future climatic conditions, and on how relevant information for climate risk analysis, vulnerability and adaptation may be co-created with users, e.g., in terms of tailored climate services. For this aim, this Interdisciplinary and Transdisciplinary Session invites contributions that will serve to (i) better understand the mechanisms behind high impact events from a transdisciplinary and interdisciplinary perspective, e.g. case studies and the assessment of past high impact events, including detection and attribution; (ii) project changes to high impact events through, e.g. high resolution climate and impacts modelling (including economic modelling); (iii) produce climate information at the relevant scales (downscaling); and co-create climate services with users to help deal with the risk and/or impacts of high-impact events, e.g. risk analysis and climate adaptation. Abstracts that highlight recent advances from a transdisciplinary perspective for example through the innovation of climate services will be particularly encouraged. Authors and contributors to this session will be offered to present their work in a Special Issue of the journal “Sustainability”.

One of the big challenges in Earth system science consists in providing reliable climate predictions on sub-seasonal, seasonal, decadal and longer timescales. The resulting data have the potential to be translated into climate information leading to a better assessment of multi-scale global and regional climate-related risks.
The latest developments and progress in climate forecasting on subseasonal-to-decadal timescales will be discussed and evaluated in this session. This will include presentations and discussions of predictions for a time horizon of up to ten years from dynamical ensemble and statistical/empirical forecast systems, as well as the aspects required for their application: forecast quality assessment, multi-model combination, bias adjustment, downscaling, etc.
Following the new WCPR strategic plan for 2019-2029, prediction enhancements are solicited from contributions embracing climate forecasting from an Earth system science perspective. This includes the study of coupled processes, impacts of coupling and feedbacks, and analysis/verification of the coupled atmosphere-ocean, atmosphere-land, atmosphere-hydrology, atmosphere-chemistry & aerosols, atmosphere-ice, ocean-hydrology, ocean-ice, ocean-chemistry and climate-biosphere (including human component). Contributions are also sought on initialization methods that optimally use observations from different Earth system components, on assessing and mitigating the impacts of model errors on skill, and on ensemble methods.
We also encourage contributions on the use of climate predictions for climate impact assessment, demonstrations of end-user value for climate risk applications and climate-change adaptation and the development of early warning systems.

A special focus will be put on the use of operational climate predictions (C3S, NMME, S2S), results from the CMIP5-CMIP6 decadal prediction experiments, and climate-prediction research and application projects (e.g. EUCP, APPLICATE, PREFACE, MIKLIP, MEDSCOPE, SECLI-FIRM, S2S4E).

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

Drought and water scarcity are important issues in many regions of the Earth, requiring innovative hydro-meteorological monitoring, modelling and forecasting tools to evaluate the complex impacts on the availability and quality of water resources. While drought describes a natural hazard, water scarcity is related to long-term unsustainable use of water resources and associated socio-economic aspects. Both phenomena are, however, closely linked, with the complex interrelationship requiring careful attention.
While an increase in the severity and frequency of droughts can lead to water scarcity situations, particularly in regions that are already water stressed, overexploitation of available water resources can exacerbate the consequences of droughts. In the worst case, this can lead to long-term environmental and socio-economic impacts. Particular attention should, therefore, be paid to the feedbacks between these two phenomena, including the potential impacts of climate change. It is therefore necessary to improve both monitoring and sub-seasonal to seasonal forecasting for droughts and water availability, and to develop innovative indicators and methodologies that translate the information provided into effective drought early warning and risk management.
This session will address statistical, remote sensing and physically-based techniques, aimed at monitoring, modelling and forecasting hydro-meteorological variables relevant to drought and/or water scarcity. These include, but are not limited to, precipitation, snow cover, soil moisture, streamflow, groundwater levels and extreme temperatures. The development and implementation of drought indicators meaningful to decision making processes, and ways of presenting and explaining them to water managers, policy makers and other stakeholders, are further issues to be addressed.
The session aims to bring together scientists, practitioners and stakeholders in the fields of hydrology and meteorology, as well as in the field of water resources and/or risk management; interested in monitoring, modelling and forecasting drought and water scarcity, and in analyzing their interrelationships, hydrological impacts, and the feedbacks with society. Particularly welcome are applications and real-world case studies in regions subject to significant water stress, where the importance of drought warning, supported through state-of-the-art monitoring and forecasting of water resources availability is likely to become more important in the future.

Intense rainfall and/or orographic precipitation events in small and medium size catchments can trigger flash floods, which are characterized by very short response times and high specific peak discharges. Under appropriate topographic conditions, such rainstorms also cause debris flows or shallow landslides mobilizing large amounts of unconsolidated material. Although significant progress has been made in the last decade in the management of flash floods related risks, these events remain poorly understood and their predictability is limited by a high non-linearity in the hydrological response, related to threshold effects and structured heterogeneity at all scales. In addition, predicting the initiation and runout of rainfall-induced landslides and their interactions with hydrological and hydraulic processes is still affected by large uncertainties. Therefore, improving the flash floods understanding, forecasting and risk management capacities requires multi-disciplinary approaches, as well as innovative measurements and modelling approaches as these events often occur in ungauged basins.

This session welcomes contributions illustrating current advances and approaches in monitoring, modelling, forecasting and warning flash floods and associated geomorphic processes. Contributions documenting the societal responses and impacts, and analysing risk management systems are also welcome. The session will cover the following main scientific themes:
- Development of new measurement techniques adapted to flash floods monitoring and quantification of the associated uncertainties
- Use of remote sensing data, weather radar, and lightning for improving forecasting models input data
- Development of modelling tools for predicting and forecasting flash floods and/or rainfall-induced landslides in gauged and ungauged basins
- Use of new criteria such as specific “hydrological signatures” for model and forecast evaluation
- Identification of processes leading to flash flood events and/or rainfall-induced landslides from data analysis and/or modelling, and of their characteristic space-time scales
- Evolutions in flash-flood characteristics possibly related to changing climate.
- Observation, understanding and prediction of the social vulnerability and social response to flash floods and/or associated landsliding
- Flash flood and/or rainfall-induced landslide risk assessment using multi-disciplinary approaches and warning systems, and evaluation of the relevance of those systems.

Ensemble hydro-meteorological prediction systems have higher forecasting skills than their deterministic counterparts, which in turn can improve risk assessment decision-making in operational water management. Ensemble forecasts are now common many operational settings, such as flood and drought forecasting, and can be used in applications from forecasting extreme events to optimisation of water resources allocation. However, moving from deterministic forecasting systems to a probabilistic framework poses new challenges but it also opens new opportunities for the developers and users of ensemble forecasts to improve their systems.

This session brings together scientists, forecasters, practitioners and stakeholders interested in exploring the use of ensemble hydro-meteorological forecast techniques in hydrological applications: e.g., flood control and warning, reservoir operation for hydropower and water supply, transportation and agricultural management. The session will also explore new forecast products and systems in terms of their implementation and practice for real-time forecasting.

Contributions will cover, but are not restricted to, the following topics:
- The design of ensemble prediction systems
- Requirements and techniques to improve the skill of hydro-meteorological ensemble forecasting systems
- Methods to bias correct and calibrate ensemble forecasts
- Methods to assess the quality or benchmark the performance of ensemble forecasts
- Approaches to deal with forecast scenarios in real-time
- Strategies for balancing human expertise and automation in ensemble forecasting systems
- Challenges of the paradigm shift from deterministic to ensemble forecasts
- Methods and products that include forecaster knowledge to improve the interpretation of ensemble forecasts
-Use of cost/loss scenarios for optimising systems
- Approaches for efficient training (including role-playing games) on the use and value of ensemble predictions.

The session welcomes new experiments and practical applications showing successful experiences, as well as problems and failures encountered in the use of uncertain forecasts and ensemble hydro-meteorological forecasting systems. Case studies dealing with different users, temporal and spatial scales, forecast ranges, hydrological and climatic regimes are welcome.

Solicited speaker Niko Wanders from Utrecht University: From seasonal forecasting to water management decisions: challenges and opportunities

The session is part of the HEPEX international initiative: www.hepex.org

This session will address the understanding of sources of predictability and quantification and reduction of predictive uncertainty of hydrological extremes in operational hydrologic forecasting. Including uncertainty estimation in operational forecasting systems is becoming a more common practice. However, a significant research challenge and central interest of this session is to understand the sources of predictability and development of approaches, methods and techniques to enhance predictability (e.g. accuracy, reliability etc.) and quantify and reduce predictive uncertainty in general. Providing uncertainty estimates for integrated catchment models involving forecasting models, either as a cascade or as alternative models, can prove particularly challenging and are an issue of interest to the session. Data assimilation or pre-/post-processing in real-time can provide important ways of improving the quality (e.g. accuracy, reliability) and reducing the uncertainty of hydrological forecasts. Methods that help update forecasts in real-time to reduce bias and increase accuracy, and case study demonstrations of their use, are of interest to this session.
The models involved with the methods for predictive uncertainty, data assimilation, post-processing and decision-making may include catchment models, runoff routing models, groundwater models, coupled meteorological-hydrological models as well as combinations of these. Demonstrations of the sources of predictability and subsequent reduction in predictive uncertainty at different scales through improved representation of model process (physics, parameterization, numerical solution, data support and calibration) and error, forcing and initial state are of special interest to the session.
Contributions are expected to address the following issues:
(i) Sources of predictability (model, forcing, initial conditions)
(ii) Quantification and reduction of predictive uncertainty
(iii) Real-time data assimilation
(iii) Untangling sources of uncertainty in the meteorological-hydrological forecasting chain
(iv) Effect of (improved) representation of model process on forecast quality and predictive uncertainty
(v) Methods for preparing meteorological predictions as input to real-time hydrological probability forecasts
(vi) Verification (methods) of hydrologic forecasts
(vii) Case studies of the above

Solicited speaker is Maurizio Mazzoleni (from Uppsala University) who will give a talk about Real-time assimilation of crowdsourced observations in hydrological and hydraulic models.

This interactive PICO session aims to bridge the gap between science and practice in operational forecasting for different water-related natural hazards. Operational (early) warning systems are the result of progress and innovations in the science of forecasting. New opportunities have risen in physically based modelling, coupling meteorological and hydrological forecasts, and ensemble forecasting. However, once a system is operational, the development often continues more in the field of applied research or consultancy. Furthermore, development of these types of systems is usually performed within one field of expertise. Forecasting warning research can be more effective when these efforts and experiences are combined.

The focus of this session will be on bringing the expertise from different fields together as well as exploring differences, similarities, problems and solutions between forecasting systems for varying natural hazards. Real-world case studies of system implementations - configured at local, regional and national scales - will be presented, including trans-boundary issues. An operational warning system can include monitoring of data, analysing data, making forecasts, giving warning signals and suggesting response measures.

Contributions addressing the following topics are welcome:
- Applications of forecasting warning systems for water-related natural hazards, such as: flood, drought, tsunami, landslide, hurricane etc.
- Applications of forecasting warning systems for other hazards, such as: pollution
- Operational data validation and calibration
- Operational warning methods and procedures
- Real time control for hazards
- The operational system as a tool for improved risk management and decision making
- Performance of operational forecasts, event analysis
- Serious games and training with operational systems
- Structure of operational forecasting systems
- Techniques/applications to better communicate forecasts with users - such as visualization tools and impact assessments
- Impact-based forecasts for early action, response and control.

Ongoing climate change and a shorter return period of climate and hydrological extremes has been observed to affect the distribution and vitality of ecosystems. In many regions, available water is a crucial point of survival. Risk can be enhanced by the exposure and/or by the vulnerability of the affected ecosystem.
The session focuses on the complex assessment of all determining factors through a joint utilization of a broad spectrum of databases and methods (e.g. field and laboratory measurements, remote sensing, modelling and monitoring techniques) that can provide a suitable basis for developing long-term strategies for adaptation.
The session should provide a multidisciplinary platform for sharing experiences and discussing results of local and catchment scale case studies from a wider range of relevant fields such as
• observed impacts and damage chains in natural ecosystems induced by climate and hydrological extremes;
• correlation between the underlying environmental factors (e.g. climate, water holding capacity, soil characteristics) and the distribution/vitality of ecosystems;
• integrated application or comparison of databases and methods for the identification and complex assessment of ecosystem responses to abiotic stress factors;
• expected tendencies of abiotic risk factors affecting and limiting the survival of the vulnerable species.
Contributions are encouraged from international experiences, ongoing research activities as well as national, regional and local initiatives.

Fire is a global phenomenon influencing ecosystem functioning, carbon stocks and fluxes, and atmospheric composition, with large impacts on human health, safety and economy. The relative importance of climate, vegetation and humans as drivers of fire activity varies across spatial and temporal scales. Multiscale and interdisciplinary assessments of fire behavior are required to understand global climate-fire feedbacks, as well as regional interactions between vegetation and humans, and fire.
Fire influences the global carbon cycle among others through its carbon emissions and post-fire ecosystem carbon sequestration. In addition, black carbon (also known as pyrogenic carbon, charcoal, soot) is a crucial component in the carbon cycle, yet uncertainties remain regarding sizes, losses and fluxes between land, rivers, oceans and atmosphere.
Remote sensing provides baseline information for all stakeholders involved in monitoring of biomass burning at different scales and for understanding how ecosystems respond to fires. However, there are still large uncertainties in satellite-based active fire, burned area, and fire emissions estimates, in part due to the complexity and diversity of the ecosystems affected. Building on the environmental significance and scientific challenges described above, this session will bring together fire scientists working on biomass burning monitoring and early warning systems. The aim of this session is to improve the understanding of interactions between fire, vegetation, carbon, climate and humans. We invite contributions developing or using remote sensing datasets, in situ observations, charcoal records, laboratory experiments and modeling approaches. We welcome studies that help to improve our understanding of (1) the relative importance of climate, vegetation and humans on fire occurrence across spatial and temporal scales (2) the impacts of fire on vegetation, atmosphere and society, (3) feedbacks between fire, vegetation and climate, and (4) the role of fire in the carbon cycle, with special focus on the transfer of black carbon and other fire markers from terrestrial ecosystems to aquatic environments, and their biogeochemical fate in these environments, (5) innovative use of remote sensing technologies (LIDAR, infrared cameras, drones) for fuel characterization, fire detection and monitoring; (6) algorithms/models applicable to regional-to-global scale fire analyses exploring active fire detection and characterization (e.g., fire radiative power, area affected, combustion phase), burned area mapping, atmospheric emissions and smoke transport, (7) fire product validation and error assessment, (8) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems, addressing specific needs of operational fire behavior modeling.

Invited speakers:
Emilio Chuvieco, University of Alcala
Elena Kukavskaya, Sukachev Institute of Forest, Russian Academy of Sciences

Estimating the impact of climate change on both the natural and socio-economic environment plays an important role in informing a range of national and international policies, including energy, agriculture and health. Understanding these impacts, and those avoided, has never been more pertinent since the adoption of the 2015 Paris Agreement, which sought to hold “the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C, recognizing that this would significantly reduce the risks and impacts of climate change".

Policies may aim to mitigate (i.e. reduce emissions), counteract (i.e. negative emissions) and/or adapt to anthropogenic climate change and it is equally important to quantify the impact of implementing these options. While rapid, deep mitigation is clearly a pre-requisite to success, delays to such measures imply a greater reliance upon large scale negative emissions technologies. Those based on land are likely to face competing pressure from wide ranging economic activity, and knowledge of these interactions and synergies is limited. Similarly while adaptation options are wide ranging, the uses of nature-based solutions, which often provide mitigation co-benefits and are often highly cost effective, are under-researched and rarely integrated into overall natural hazard or climate change risk management strategies.

Furthermore, the methods used to evaluate impact in the climate context are many and varied, including empirical, econometric and process-based. These methods continue to evolve implying that the assessment of impact may depend upon the analytical approach chosen.

This inter- and transdisciplinary session aims to draw together scientists, developing climate-impact evaluation methods, evaluating the impact (or avoided impact) of anthropogenic climate change upon natural and socio-economic environments, investigating the potential for mitigation and counteraction options to reduce long term risk, and studying the value of multiple adaptation options to stakeholders when planning how to manage vulnerability.

Invited speaker: Sonia Seneviratne

More than 75% of the volcanic activity on Earth occurs underwater. Recent unrest observed at many submarine volcanoes raises serious concerns regarding the level of risk posed to local communities. Many parameters of submarine to emergent volcanic activity are under active investigation, including how explosive activity varies with water depth, magma properties and magma composition. This session brings together experts from diverse disciplines to explore hazards posed to island and coastal communities as well as mechanisms of submarine to emergent volcanic activity.

The session will include presentations that integrate innovative and emerging technologies to enable focused and multi-disciplinary studies of recent and ancient eruptions and their products, as well as breakthrough developments in understanding the impact of disastrous submarine volcanic hazards on present and past societies.

We call for abstracts in the following areas:
- Identification of submarine volcanic hazards such as explosive eruptions, volcanic earthquakes, submarine landslides, hydrothermal emissions and volcanogenic tsunamis.
- Studies of the mechanics of submarine and emergent volcanic eruptions and formation of oceanic islands.
- Investigations of optimal monitoring technologies and state of the art methods that provide new insights into explorations of submarine volcanoes, which host hydrothermal systems, mineral deposits and biomediated processes.
- Recommendations for volcanic crisis management, public awareness and preparedness through an improved understanding of the hazards and impacts of submarine volcanoes.

The European countries are often recognised as the cradle of some of the world’s most important cultural heritage in stone. The cultural, artistic and social importance of stone monuments and lithic works of art evidences the general need to safeguard our praiseworthy cultural heritage. Unfortunately, we are confronted with some problems concerning their conservation, such as the increase of atmospheric contamination, the complex interactions between physical, chemical and biological factors, vandalism, lack of maintenance, and inefficient conservation treatments. This session will focus on the novel approaches that have been recently developed in the field of stone cultural heritage. The new emerging technologies, together with the variety of strategies, methodologies and biotechnological approaches available today show the wide range of possibilities that can be applied to stone heritage conservation. We invite studies devoted to: (i) novel tools for the identification of microorganisms and metabolites responsible for stone biodeterioration; (ii) biomaterials used for the preservation of granite and limestone materials; (iii) natural products from plants or microorganisms as innovative bioactive compounds for controlling biodeterioration; (iv) biotechnological approaches for the preservation of stone-built heritage and removal of sulphates, nitrates or organic substances from stone walls; (v) bioremediation strategies for building restoration. Experimental design setups, laboratory-based assays and field tests are also welcomed.

The session deals with the documentation and modelling of the tectonic, deformation and geodetic features of any type of volcanic area, on Earth and in the Solar System. The focus is on advancing our understanding on any type of deformation of active and non-active volcanoes, on the associated behaviours, and the implications for hazards. We welcome contributions based on results from fieldwork, remote-sensing studies, geodetic and geophysical measurements, analytical, analogue and numerical simulations, and laboratory studies of volcanic rocks.
Studies may be focused at the regional scale, investigating the tectonic setting responsible for and controlling volcanic activity, both along divergent and convergent plate boundaries, as well in intraplate settings. At a more local scale, all types of surface deformation in volcanic areas are of interest, such as elastic inflation and deflation, or anelastic processes, including caldera and flank collapses. Deeper, sub-volcanic deformation studies, concerning the emplacement of intrusions, as sills, dikes and laccoliths, are most welcome.
We also particularly welcome geophysical data aimed at understanding magmatic processes during volcano unrest. These include geodetic studies obtained mainly through GPS and InSAR, as well as at their modelling to imagine sources.


The session includes, but is not restricted to, the following topics:
• volcanism and regional tectonics;
• formation of magma chambers, laccoliths, and other intrusions;
• dyke and sill propagation, emplacement, and arrest;
• earthquakes and eruptions;
• caldera collapse, resurgence, and unrest;
• flank collapse;
• volcano deformation monitoring;
• volcano deformation and hazard mitigation;
• volcano unrest;
• mechanical properties of rocks in volcanic areas.

Over the past few years, major technological advances allowed to significantly increase both the spatial coverage and frequency bandwidth of geochemical and geophysical observations at active volcanoes. Establishment of high-rate GPS networks, continuous gravity meters, dense arrays of broad-band seismometers, and networks of instruments for the quantitative measurement of volcanic gas emissions now permits an unprecedented, multi-parameter vision of the surface manifestations of mass transport beneath volcanoes. Accompanying these progresses are new models and processing techniques leading to innovative paradigms for the interpretation and inversion of observational data. Within this context, this session aims at bringing together a multidisciplinary audience to discuss about the most recent innovations in monitoring approaches and to present observations, methods and models that increase our understanding of volcanic processes.

We welcome contribution related to (1) New instruments and techniques for the measurement of geophysical and geochemical parameters, from in-situ methods to ground-, air- and space-based remote sensing techniques; (2) Reports of significant case histories, documenting the relationships between the measured parameters and the evolving volcanic processes; (3) New modelling frameworks for the interpretation of the observed data, and their significance in terms of eruption forecasting.

The session will provide an opportunity to discuss volcanic activity from a monitoring perspective on a wide range of volcanoes. We therefore encourage submission of papers that are easily understandable to a broad, multi-disciplinary audience.

Volcanic edifices consist of diverse suites of pyroclastic successions, originated from primary (e.g. tephra fall, lava flow) and reworking processes (e.g. alluvial activity). The volcanoclastic sediments have witnessed the magma fragmentation and subsequent transportation mechanism as flow, turbulent current or tephra fall. Such pyroclastic deposits therefore hold key evidence to understand volcano-stratigraphy, eruption re-occurrence rates, and dominant transportation modes. This session aims to discuss sedimentary and volcanological aspects of volcanoclastic deposits. We invite presentations covering (1) field-based description and interpretation of volcanoclastic sediments, (2) reconstruction of eruptive and sediment transport processes, (3) experimental and numerical simulation of volcano-related sediment transport, and (4) development of new methodologies to understand the formation of volcanoclastic sediments. These topics are critical to understand volcanic phenomena and to improve upon existing volcanic monitoring efforts, and to forecast volcanic hazards in the future.

Glaciers and volcanoes interact in a number of ways, including instances where volcanic/geothermal activity alters glacier dynamics or mass balance, via subglacial eruptions or the deposition of supraglacial tephra. Glaciers can also impact volcanism, for example by directly influencing mechanisms of individual eruptions resulting in the construction of distinct edifices. Glaciers may also influence patterns of eruptive activity when mass balance changes adjust the load on volcanic systems. However, because of the remoteness of many glacio-volcanic environments, these interactions remain poorly understood.
In these complex settings, hazards associated with glacier-volcano interaction can vary from lava flows to volcanic ash, lahars, pyroclastic flows or glacial outburst floods. These can happen consecutively or simultaneously and affect not only the earth, but also glaciers, rivers and the atmosphere. As accumulating, melting, ripping or drifting glaciers generate signals as well as degassing, inflating/ deflating or erupting volcanoes, the challenge is to study, understand and ultimately discriminate these potentially coexisting signals. We wish to fully include geophysical observations of current and recent events with geological observations and interpretations of deposits of past events.
We invite contributions that deal with the mitigation of the hazards associated with ice-covered volcanoes, that improve the understanding of signals generated by ice-covered volcanoes, or studies focused on volcanic impacts on glaciers and vice versa. Research on recent activity is especially welcomed. This includes geological observations e.g. of deposits in the field or remote-sensing data, together with experimental and modelling approaches. We also invite contributions on past activity and glaciovolcanic deposits. We aim to bring together scientists from volcanology, glaciology, seismology, geodesy, hydrology, geomorphology and atmospheric science in order to enable a broad discussion and interaction.

Volcanic Islands are environments created by the growth of volcanoes in the sea, modified by geologic, environmental, biological and human activity. They are highly varied in geology, terrain, environment and social makeup. They are fragile environments in that they respond rapidly to global or local changes in a way that links geology, social activity and environment. Dealing with a complex object such as volcanic island requires a multidisciplinary approach on their on-land and submarine processes that crosses scientific, social and economic boundaries. From a geological and geophysical perspective there are numerous aspects that need to be addressed to acquire a comprehensive picture of how volcanic islands are born, grow up, evolve and die. These include their geodynamic setting, magmatism, volcanism, hydrothermalism, tectonics, and erosion and material transport, as well as their associated hazards and risks, environmental change record, or energy and economic resources. With the aim at integrating all this multidisciplinary research into a single forum of discussion, we offer this scientific session on Volcanic Islands, in which any geological and geophysical research on such complex environments will be more than welcome.

Rockfalls, rockslides and rock avalanches are fundamental modes of erosion on steep hillslopes, and among the primary hazards in steep alpine terrain. To better understand the processes driving rock slope degradation, mechanisms contributing to the triggering, transport, and deposition of resulting rock slope instabilities, and mitigation measures for associated hazards, we must develop insight into both the physics of intact and rock mass failure and the dynamics of transport processes. This session aims to bring together state-of-the-art methods for predicting, assessing, quantifying, and protecting against rock slope hazards. We seek innovative contributions from investigators dealing with all stages of rock slope hazards, from weathering and/or damage accumulation, through detachment, transport and deposition, and finally to the development of protection and mitigation measures. In particular, we seek studies presenting new theoretical, numerical or probabilistic modelling approaches, novel data sets derived from laboratory, in situ, or remote sensing applications, and state-of-the-art approaches to social, structural, or natural protection measures.

Climate changes (CC) are expected affecting weather forcing regulating the triggering and reactivation of slope movements. The influence of CC on landslides can be different, according to the area, the time horizon of interest and the actual trends of socio-economic factors driving greenhouse gases concentration. However, even the simple identification of weather patterns regulating landslide occurrence represents a not trivial issue, also assuming steady conditions, due to crucial role played by geomorphological details.
In last years, such elements partly prevented the investigations aimed to assess how CC influence slope stability at different temporal and spatial scales.
In this regard, the Session has the main aim to gather test cases and investigations carried out in different geographical contexts in evaluation of ongoing and future landslide activity.
Researches may concern: (i) modeling of future slope stability conditions exploiting downscaled climate projections or (ii) analyses of historical records of landslides (using both historical research or paleo-evidences) and climate variables and their combinations.
Analysis at different detail from slope to regional scale to global scale, considering variations in landslide occurrence, frequency, susceptibility, hazard and risk result of interest. Nevertheless, studies considering the coupled effect of environmental (e.g., land use/cover) and climate changes will be taken into account.

Weathering, tectonics, gravitational and volcanic processes can transform the regular sediment delivery from unstable slopes in catastrophic landslides. Mass spreading and mass wasting processes can potentially evolve in rapid landslides are among the most dangerous natural hazards that threaten people and infrastructures, directly or through secondary events like tsunamis.

Documentation and monitoring of these phenomena requires the adoption of a variety of methods. The difficulties in detecting their initiation and propagation have progressively prompted research into a wide variety of monitoring technologies. Nowadays, the combination of distributed sensor networks and remote sensing techniques represents a unique opportunity to gather direct observations. A growing number of scientists with diverse backgrounds are dealing with the monitoring of processes ranging from volcano flak deformations to large debris flows and lahars. However, there is a need of improving quality and quantity of both documentation procedures and instrumental observations that would provide knowledge for more accurate hazard assessment, land-use planning and design of mitigation measures, including early warning systems. Successful strategies for hazard assessment and risk reduction would imply integrated methodology for instability detection, modeling and forecasting. Nevertheless, only few studies exist to date in which numerical modelling integrate geological, geophysical, geodetic studies with the aim of understanding and managing of terrestrial and subaqueous volcano slope instability.

Scientists working in the fields of hazard mapping, modelling, monitoring and early warning are invited to present their recent advancements in research and feedback from practitioners and decision makers. We encourage multidisciplinary contributions that integrate field-based on-shore and submarine studies (geological, geochemical), geomorphological mapping and account collection, with advanced techniques, as remote sensing data analysis, geophysical investigations, ground-based monitoring systems, and numerical and analogical modelling of volcano spreading, slope stability and debris flows.

Among the many mitigation measures available for reducing the risk to life related to landslides, early warning systems certainly constitute a significant option available to the authorities in charge of risk management and governance. Landslide early warning systems (LEWS) are non-structural risk mitigation measures applicable at different scales of analysis: slope and regional. Systems addressing single landslides at slope scale can be named local LEWS (Lo-LEWS), systems operating over wide areas at regional scale are referred to as territorial systems (Te-LEWSs). An initial key difference between Lo-LEWSs and Te-LEWSs is the knowledge “a priori” of the areas affected by future landsliding. When the location of future landslides is unknown and the area of interest extends beyond a single slope, only Te-LEWS can be employed. Conversely, Lo-LEWSs are typically adopted to cope with the risk related to one or more known well-identified landslides.

Independently by the scale of analysis, the structure of LEWS can be schematized as an interrelation of four main modules: setting, modelling, warning, response. However, the definition of the elements of these modules and the aims of the warnings/alerts issued considerably vary as a function of the scale at which the system is employed.

The session focuses on landslide early warning systems (LEWSs) at both regional and local scales. The session wishes to highlight operational approaches, original achievements and developments useful to operate reliable (efficient and effective) local and territorial LEWS. Moreover, the different schemes describing the structure of a LEWS available in literature clearly highlight the importance of both social and technical aspects in the design and management of such systems.

For the above-mentioned reasons, contributions addressing the following topics are welcome:
• rainfall thresholds definition;
• monitoring systems for early warning purposes;
• warning models for warning levels issuing;
• performance analysis of landslide warning models;
• communication strategies;
• emergency phase management;
• landslide risk perception.

Landslides are ubiquitous geomorphological phenomena with potentially catastrophic consequences. In several countries landslide mortality can be higher than that of any other natural hazard. Predicting landslides is a difficult task that is of both scientific interest and societal relevance that may help save lives and protect individual properties and collective resources. The session focuses on innovative methods and techniques to predict landslide occurrence, including the location, time, size, destructiveness of individual and multiple slope failures. All landslide types are considered, from fast rockfalls to rapid debris flows, from slow slides to very rapid rock avalanches. All geographical scales are considered, from the local to the global scale. Of interest are contributions investigating theoretical aspects of natural hazard prediction, with emphasis on landslide forecasting, including conceptual, mathematical, physical, statistical, numerical and computational problems, and applied contributions demonstrating, with examples, the possibility or the lack of a possibility to predict individual or multiple landslides, or specific landslide characteristics. Of particular interest are contributions aimed at: the evaluation of the quality of landslide forecasts; the comparison of the performance of different forecasting models; the use of landslide forecasts in operational systems; and investigations of the potential for the exploitation of new or emerging technologies e.g., monitoring, computational, Earth observation technologies, in order to improve our ability to predict landslides. We anticipate that the most relevant contributions will be collected in the special issue of an international journal.

This session aims to discuss hydrology related to landslide occurrence both on local and regional scale. It focuses on the detailed analysis and modelling of hydrological processes on hillslope and catchment scale in order to improve our understanding and prediction of the spatio-temporal patterns of landslide triggering and slope deformation mechanisms.

Water circulation within a catchment and the resultant transient changes in both shallow and deep hydrological systems is the most common controlling and triggering factor of slope movements. However, incorporation of hydrological process knowledge in slope failure analysis, such as water-rock interaction, water storage, dynamic preferential flows or the influence of frost conditions to name a few, still lags behind. Also, the inclusion of regional hydrological information in rainfall thresholds analysis is underdeveloped. The research frontiers are connected with the complexity of real landslides such as the difficulty to monitor groundwater levels or soil moisture contents in unstable terrain and over large areas, the difficulty to understand the water pathways within heterogeneous regolith soils and fractured bedrock, which are the characteristic substratum where landslides occur, and the complexity of dynamically quantifying and predicting the hydrological exchange between a potentially unstable slope and its surroundings.

We invite research ranging from unsaturated zone, hillslope processes and regional hydrology which are applied to landslide research in a broad sense: ranging from soil slips to large scale deep-seated slope deformation. The session will give time to both laboratory and field monitoring studies, preferably quantitative, and based on novel measurement and modelling techniques. We invite pioneering research that includes hydrological information in local and regional hazard assessment. Moreover, we welcome studies that incorporate hydrological process knowledge in the geotechnical analysis and modelling setting the next step to improve landslide hazard analysis.

Over the last decade, many researchers and practitioners have contributed to consolidating a landslide and debris flows risk management framework, enhancing techniques and pioneering applications to problems that are otherwise difficult to resolve using conventional methods. However, as extreme rainfall events occur with increasing frequency due to climate change, the threat posed by compound geohazards will inevitably increase. Clearly, a new paradigm of mountain hazard mitigation and management is required. Therefore, developing risk analysis models, which could integrate the hazard dynamic process by using both practical experience and numerical simulation, is a key scientific challenge for effective disaster risk reduction. This session focuses on disaster risk analysis and management methods as well as their coherence with the mechanisms of compound hazards, including initiation, transportation, and deposition. The topics of the presentations include but are not limited to:
(a) Advanced methodology of data collection in the field, the improvement and development of sensor technology and the real time data collection of debris flow and landslides hazards for a better dimensioning of mitigation measures.
(b) Numerical simulation of compound geohazards at the local scale and global scale.
(c) Innovative applications remote sensing data for hazard, vulnerability and risk mapping.
(d) Advances in risk analysis methods by integrating new technologies in hazard data retrieving, hazard simulation and vulnerability assessment of elements at risk.
(e) Optimizing the engineering design for current hazard mitigation and control structure and develop new techniques for disaster control.
Additionally, we welcome submissions concentrating on big data processing, machine learning related to vulnerability, and resilience of the elements at risk.

In recent years, debris flows are becoming more frequent and larger in magnitude due to global climate change, resulting in the loss of human life and substantial damage to infrastructure. In light of such trends, there is increasing national interest for the development of proactive technologies to prevent and mitigate debris flow disasters. Although many disaster prevention facilities are being built, there are still questions regarding the accuracy and reliability of the methodologies and techniques being utilized for the design of these structures. Therefore, in order to improve existing disaster prevention measures and effectively reduce damage, it is necessary to make scientific and technological strides at each stage of the design process of disaster prevention facilities. This session mainly focuses on methods for the prevention and mitigation of debris flow disasters, including the following topics:
(1) Advanced data collection methods for the collection of site properties such as the utilization of UAV-based LiDAR, spectroscopic techniques, etc.
(2) Prediction techniques that provide quantitative information of debris flow through big data analysis, machine learning models, and numerical modeling
(3) Performance analysis of various types of disaster prevention facilities based on small-scale & large-scaled experiments and numerical simulations
(4) Optimum design of disaster prevention facilities through sensitivity analysis and parametric studies
We also welcome submissions that focus on new techniques and design methodologies related to the 4th industrial revolution.

Keywords
Debris flow, Disaster prevention facilities, Optimum design, Experimental and numerical studies, Big data, Machine learning techniques

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Landslides are one of the most widespread and destructive natural hazards in the world. However, it is possible to reduce hazards caused by the landslides by monitoring and/or early warning systems. Today, lots of systems are available for the purpose and new systems have been developing continuously. The aim of this session is to gain a complete knowledge about the landslide monitoring and early warning systems by introducing different systems used, learning new technologies about the topic, investigating their properties, comparing the techniques and devices.

Keywords: Landslide monitoring systems, early warning systems

Remarkable technological progress in remote sensing and geophysical surveying, together with the recent development of innovative data treatment techniques are providing new scientific opportunities to investigate landslide processes and hazards all over the world. Remote sensing and geophysics, as complementary techniques for the characterization and monitoring of landslides, offer the possibility to effectively infer and correlate an improved information of the shallow -or even deep- geological layers for the development of conceptual and numerical models of slope instabilities. Their ability to provide integrated information about geometry, rheological properties, water content, rate of deformation and time-varying changes of these parameters is ultimately controlling our capability to detect, model and predict landslide processes at different scales (from site specific to regional studies) and over multiple dimensions (2D, 3D and 4D).

This session welcomes innovative contributions and lessons learned from significant case studies using a myriad of remote sensing and geophysical techniques and algorithms, including optical and radar sensors, new satellite constellations (including the emergence of the Sentinel-1A and 1B), Remotely Piloted Aircraft Systems (RPAS) / Unmanned Aerial Vehicles (UAVs) / drones, high spatial resolution airborne LiDAR missions, terrestrial LIDAR, Structure-from-Motion (SfM) photogrammetry, time-lapse cameras, multi-temporal Synthetic Aperture Radar differential interferometry (DInSAR), GPS surveying, Seismic Reflection, Surface Waves Analysis, Geophysical Tomography (seismic and electrical), Seismic Ambient Vibrations, Acoustic Emissions, Electro-Magnetic surveys, low-cost (/cost-efficient) sensors, commercial use of small satellites, Multi-Spectral images, Real time monitoring, in-situ sensing, etc.

The session will provide an overview of the progress and new scientific approaches of Earth Observation (EO) applications, as well as of surface- and borehole-based geophysical surveying for investigating landslides. A special emphasis is expected not only on the collection but also on the interpretation and use of high spatiotemporal resolution data to characterize the main components of slope stability and dynamics, including the type of material, geometrical and mechanical properties, depth of water table, saturation conditions and ground deformation over time. The discussion of recent experiences and the use of advanced processing methods and innovative algorithms that integrate data from remote sensing and geophysics with other survey types are highly encouraged, especially with regard to their use on (rapid) mapping, characterizing, monitoring and modelling of landslide behaviour, as well as their integration on real-time Early Warning Systems and other prevention and protection initiatives. Other pioneering applications using big data treatment techniques, data-driven approaches and/or open code initiatives for investigating mass movements using the above described techniques will also be considered on this session.

We invited prof. Denis Jongmans (Isterre, Université Grenoble Alpes, France), as guest speaker for the session.

Large slope instabilities have been frequently recognised in areas with different lithological (sedimentary, igneous, metamorphic rocks) and geological domains (cordillera, volcanic, etc.). Slow to very fast moving, complex mass movements have been recognized and sometimes described as strongly interrelated. Many types of slope instabilities can be grouped within this broad class, each presenting different types of hazard and risk. Some major aspects of these slope instabilities are still understudied and debated, namely:
- their regional distribution and relevance;
- triggering and controlling factors, including possible climatic changes;
- hydrological boundary conditions and evolution or control of internal hydrogeological conditions;
- mechanical controls in terms of physical mechanical properties of failure surfaces and shear zones
- dating of initial movements and reactivation episodes;
- style and state of past and present activity;
- passive and/or active control by structural-tectonic elements of the bedrock geology;
- possible styles of evolution and consequent modeling approaches;
- assessment of related hazard;
- influence of external anthropogenic factors and effects on structures and infrastructures (e.g. tunnels, dams, bridges);
- role on the general erosional and sediment yield regime at the local or mountain belt scale;
- best technologies and approaches for implementing a correct monitoring and warning system and for the interpretation of monitoring data in terms of landslide activity and behavior.

Study of these instabilities requires a multidisciplinary approach involving geology, geomorphology, geomechanics, hydro-geochemistry, and geophysics. These phenomena have been recognized on Earth as well as on other planetary bodies (e.g. Mars, Moon).
Trenching and drilling can be used for material characterization, recognition of episodes of activity, and sampling in slow slope movements. At the same time many different approaches can be used for monitoring and establishing of warning thresholds and systems for such phenomena.
Geophysical survey methods can be used to assess both the geometrical and geomechanical characteristics of the unstable mass. Different dating techniques can be applied to determine the age and stages of movement. Many modeling approaches can be applied to evaluate instability and failure (e.g. displacement and velocity thresholds), triggering mechanisms (e.g. rainfall, seismicity, volcanic eruption, deglaciation), failure propagation, rapid mass movements (rock avalanches, debris avalanches and flows), and related secondary failures (rock fall and debris flows).
Studies of hydraulic and hydrologic boundary conditions and hydrochemistry are involved, both at the moment of initial failure and, later, during reactivation. The impacts of such instabilities on structures and human activities can be substantial and of a variety of forms (e.g. deformation or failure of structures and infrastructure, burial of developed areas, etc.).
Furthermore, the local and regional sediment yield could be influenced by the landsliding activity and different landslides (e.g. type, size) can play different roles.

Mountain environments host highly dynamical and widespread erosion, sedimentation, and weathering processes. These processes cover a wide range of temporal and spatial scales, from glacial & periglacial erosion, mechanical & chemical weathering, rock fall, debris flows, landslides, to river aggradation & incision. These processes react to a wide spectrum of external and internal forcings, including permafrost retreat, strong precipitation events, climate change, earthquakes or sudden internal failure. Measuring the dynamical interplay of erosion, sedimentation as well as quantifying their rates and fluxes is an important part of source to sink research but it is highly challenging and often limited by difficult terrain. Furthermore, these dynamical processes can threaten important mountain infrastructures and need to be understood and quantified for a better societal and engineering preparation to the natural hazards they pose.

We welcome contributions investigating:
- sediment mobilization and deposition
- links between erosion, weathering, and the carbon cycle
- concepts of dynamics and connectivity of sediments and solutes
- quantification of erosion, sedimentation, and weathering fluxes in space and time
- sediment travel times and transport processes
- interaction of stabilizing and destabilizing processes on the slopes
We invite presentations that focus on conceptual, methodological, or modelling approaches or a combination of those in mountain environments and particularly encourage early career scientists to apply for this session.

In the past two decades, connectivity has emerged as a relevant conceptual framework for understanding the transfer of water and sediment through landscapes. In geomorphology, the concept has had particular success in the fields of fluvial geomorphology and soil erosion to better explain rates and patterns of hydro-geomorphic geomorphic change in catchment systems. Although much progress has been made in the understanding of the physical processes that control the flows of matter through the landscape, applying this understanding across a range of scales has long hampered progress.
This session invites contributions from all areas of geomorphology (incl. soil science and hydrology) illustrating or identifying the role of connectivity for geomorphology on a local, regional or global scale. Specific themes we would like to promote are:
- advancement of the theory of connectivity, including sound and unambiguous definitions of
connectivity and related parameters,
- methodology development for measuring connectivity in field and laboratory settings,
having a special focus on experiments for conceptualizing the different processes involved,
- the development and application of suitable models and indices of connectivity,
- determining how the concept can be used to enable sustainable land and water management
The session is organized by the IAG-working group “Connectivity in geomorphology” aiming to develop an international network of connectivity scientists, to share expertise and develop a consensus on the definition and scientific agenda regarding the emerging field of connectivity in geomorphology.

Denudation, including both chemical and mechanical processes, is of high relevance for Earth surface and landscape development and the transfers of solutes, nutrients and sediments from slope and headwater systems through the main stem of drainage basin systems to ocean basins. Denudational slope and fluvial processes are controlled by a range of environmental drivers and can be significantly affected by man-made activities. Only if we have a better quantitative knowledge of drivers, mechanisms and rates of Holocene to contemporary denudational processes across a range of different climatic environments, an improved assessment of the possible effects of global environmental changes (e.g., higher frequencies of extreme rainfall events, accelerated permafrost thawing, rapid glacier retreat), anthropogenic impacts and other disturbances (e.g., land use, fires, earthquakes) on denudation can be achieved.

This session combines contributions on denudational hillslope and fluvial processes, sedimentary budgets and landscape responses to environmental changes in different morphoclimates, including both undisturbed and anthropogenically modified landscapes. The presented studies apply a diverse set of tools and data analyses, including up to date field measurements and monitoring techniques, remotely sensed/GIS-based analyses, modelling, geochemical and fingerprinting measurements and techniques, dendrochronological approaches, and cosmogenic radionuclide dating.

This session is organized by the I.A.G./A.I.G. Working Group on Denudation and Environmental Changes in Different Morphoclimatic Zones (DENUCHANGE).

Analysing the geomorphic response to environmental change is crucial to improve the understanding, interpretation and prediction of surface process activity. Environmental drivers such as land cover and land use change, climate variability and tectonic activity are mutable in space and time, which renders the analysis of their impact on Earth surface dynamics anything but trivial. In turn, geomorphic processes have a strong impact on both natural ecosystems and artificially transformed land surfaces, with consequences ranging from increasing environmental diversity to economic damage.
This session aims to cluster latest advances in land surface research that address interrelationships between land cover dynamics, climate, evolving topography and geomorphic processes. Herein, the focus is set on the analysis, modelling and prediction of land surface processes that are linked to:
1) Natural and anthropogenic land cover dynamics, including land use changes, management practices, cultivation of field crops or grassland management, soil reinforcement of different vegetation types and parameterisation of prediction models.
2) Climate variability on a variety of spatial and temporal scales, from freeze-thaw cycles, monsoonal precipitation and extreme climatic events to Plio-Pleistocene glacial cycles and Late-Pleistocene to Holocene climatic changes.
Studies are welcome that pay heed on the geomorphic response to changes in land cover or climate, as well as the resulting feedbacks between land cover, climate and Earth surface dynamics over different temporal and spatial scales.

Analytical methods are the foundation of every scientific discipline. Therefore have they very important role in soil science and in all other related disciplines. From the choice of analytical method there depends the accuracy of researches and quality of the findings, and according to this the novelty and usefulness for society. Today we can see the usage of a very wide spectrum of methods and techniques in soil science from quite simple classical methods up to high-precision methods based on high-tech instruments. The wise usage of analytical methods and techniques allows the investigation of the processes and mechanisms in soils and to assess the status of the environment. Unfortunately, the importance of their utilisation in soil analysis is often underestimated. The main purpose of our session is to emphasize the importance of the analytical methods used to achieve the results in soil research.

The aim of this session is to present the usage of different laboratory methods and techniques in soil research and give possibility for researchers to exchange their experiences. The special goal of this session will be to promote a wider use of innovative analytical methods and hyphenated instrumental techniques for separation and determination of chemical and biochemical compounds of both known and unknown structures in mineral and organic soils, sediments, substrates and composts. Modern analytical methods and hyphenated techniques can be utilized for the investigation of the processes and mechanisms in soils like formation, transformation, and conversion.
The session is an opportunity to present the works describing the usage of wide range of equipment, from smartphones to MS in the analysis of soils. The session is not limited to these techniques or methods. Works describing the methods of soil physical analysis are accepted also. The studies connected with methodology of soil chemical analysis and particularly soil organic matter are welcome.

The Azores archipelago is located in the triple junction of the North American, Eurasian and Nubian tectonic plates. The origin of the magmatism in the archipelago remains controversial even though it has generally been associated with a mantle plume interacting with the local structural regime. Due to this peculiar geodynamic setting, earthquakes, subaerial and submarine volcanic eruptions may occur in the archipelago. The identification of possible signs of unrest of the volcanoes is challenging and much of the recent volcanic activity is characterized by the occurrence of seismic swarms, ground deformation episodes and the presence of secondary manifestations of volcanism. The archipelago is located in the vicinity of the central Northern Atlantic Ocean, what makes the islands vulnerable to storms, floods and landslides. The islands are thus ideally suited to apply different multidisciplinary methodologies for the study of geological hazards.
This session aims to focus on the Azores submarine plateau and islands as a natural laboratory for the study of different geological processes. Here, we aim at contributions from the different fields of Geology, Geophysics and Geochemistry dealing with the geodynamic context of the Azores, studying the evolution and geological diversity of the Azores and evaluate hazards that can affect the islands.

This session aims to bridge the existing gap between the process-focused fields (hydrology, geomorphology, soil sciences, natural hazards, planetary science, geo-biology, archaeology) and the technical domain (engineering, computer vision, machine learning, and statistics) where terrain analysis approaches are developed.
The rapid growth of survey technologies and computing advances and the increase of data acquisition from various sources (platforms and sensors) has led to a vast data swamp with unprecedented spatio-temporal range, density, and resolution (from submeter to global scale data), which requires efficient data processing to extract suitable information. The challenge is now the interpretation of surface morphology for a better understanding of processes at a variety of scales, from micro, to local, to global.

We aim to foster inter-disciplinarity with a focus on new techniques in digital terrain analysis and production from any discipline which touches on geomorphometry, including but not exclusive to geomorphology (e.g., tectonic/volcanic/climatic/glacial), planetary science, archaeology, geo-biology, natural hazards, computer vision, remote sensing, image processing.
We invite submissions related to the successful application of geomorphometric methods, innovative geomorphometric variables as well as their physical, mathematical and geographical meanings. Submissions related to new techniques in high-resolution terrain or global scale data production and analysis, independent of the subject, as well as studies focused on the associated error and uncertainty analyses, are also welcome. We actively encourage contributors to present work “in development”, as well as established techniques being used in a novel way. We strongly encourage young scientists to contribute and help drive innovation in our community, presenting their work to this session.

We want to foster collaboration and the sharing of ideas across subject-boundaries, between technique developers and users, enabling us as a community to fully exploit the wealth of knowledge inherent in our digital landscape. Just remember, the driver for new ideas and applications often comes from another speciality, discipline or subject: Your solution may already be out there waiting for you!

Mediterranean and other semi-arid regions are prone to cyclic droughts and flood events due to their high climate variability. Agricultural and forest practices have evolved to adapt to these conditions to increase productivity and the economic viability of these activities. Soil and water conservation (SWC) measures have been implemented in these regions to preserve natural resources while maintaining and/or increasing agriculture productivity. Currently a large variety of traditional SWC and relatively modern recent SWC approaches co-exist. However, it still been difficult to provide a robust appraisal of their effectiveness, or a detailed understanding to facilitate its adoption in situations different from those in which they have been developed, mostly through a combination of technical skills and trials and errors in commercial conditions. Finally, the use of SWC measures takes a new dimension with the prospect of climate change and the need to improve the provision of key ecosystems services.

In this frame, this session will try to promote discussion and networking among researches interested in this issue from different background, focusing on recent and past development of SWC, especially related to:
i) The effectiveness SWC measures applied in Mediterranean and other fragile environments in term of productivity, provision of ecosystem services and socio-economic impact (including both on- and off-site effects);
ii) Scientific advances in the understanding of the impact of SWC in the dynamics of hydrological and sediment fluxes, and in the spatial distribution of water and sediment sources and pathways to the improvement of best management practice (BMPs) aimed to minimize on-site and offsite erosion impacts.
iii) Advances in technologies to monitor and evaluate the efficiency of SWC and BMP by different stakeholders.
This session encompasses activities related to the implementation of Sustainable Development Goal (SDG) target 15.3 on Land Degradation Neutrality.

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.

The characterisation of linked physical properties such as elasticity, strength and permeability from outcrop to crustal scales is complicated by heterogeneity, fabric anisotropy and damage in so-called “intact rock” and by geological structure and inherited fracturing in the bulk “rock mass”. Rocks can behave as continuous or discontinuous media depending on the scale of consideration and the occurrence of discrete structures (e.g. fault zones). Moreover, rock properties and inherited geological features constrain mechanical damage processes resulting in rock mass weakening, altered permeability and hydro-mechanical coupling between rock and fluids, development of brittle shear zones, and time-dependent behavior (creep).
Despite major experimental, theoretical and modelling advances, a remaining future goal is to develop meaningful, testable methods and models that allow us to quantify the relationships between fabrics and fractures related to the geomechanical behavior of rocks on different scales and in different environmental conditions (P, T, stress, strain rate, fluids). This is critical in order to unravel the complex evolution and dynamics of the Earth’s crust, and develop predictive capabilities for geohazard and energy applications.
In this session we will bring together researchers from different communities, working on problems related to quantifying the hydro-geomechanical properties and behavior of rock masses considered either as continua or discontinua. We will explore their geological controls from the micro- to macro-scale, in a range of crustal environments and geological and geohazard applications (e.g. understanding fluid movement and hydrothermal systems at volcanoes, fluid pressure and damage evolution within fault zones. rock slope instability and related geomorphic impacts, fractured reservoir exploitation, subsidence due to drainage, induced seismicity), using experimental and numerical approaches in the laboratory and the field. We especially welcome studies that adopt novel approaches and combined methodologies.

Earthquakes occur with great spatio-temporal variability, which emerges from the complex interactions between them. Significant progress is being made towards understanding spatio-temporal correlations, scaling laws and clustering, and the emergence of seismicity patterns. New models being developed in statistical seismology have direct implications for time-dependent seismic hazard assessment and probabilistic earthquake forecasting. In addition, the increasing amount of earthquake data available on local to global scales provides new opportunities for model testing.


This session focuses both on recent insights on the physical processes responsible for the distribution of earthquakes in space and time, and on new models and techniques for quantifying the seismotectonic process and its evolution. Particular emphasis will be placed on:
- physical and statistical models of earthquake occurrence;
- analysis of earthquake clustering;
- spatio-temporal properties of earthquake statistics;
- quantitative testing of earthquake occurrence models;
- implications for time-dependent hazard assessment;
- methods for earthquake forecasting;
- data analyses and requirements for model testing.

Confirmed solicited speaker: Danijel Schorlemmer (GFZ - German Research Center for Geosciences, Potsdam, Germany)

From the real-time integration of multi-parametric observations is expected the major contribution to the development of operational t-DASH systems suitable for supporting decision makers with continuously updated seismic hazard scenarios. A very preliminary step in this direction is the identification of those parameters (seismological, chemical, physical, biological, etc.) whose space-time dynamics and/or anomalous variability can be, to some extent, associated with the complex process of preparation of major earthquakes.
This session wants then to encourage studies devoted to demonstrate the added value of the introduction of specific, observations and/or data analysis methods within the t-DASH and StEF perspectives. Therefore studies based on long-term data analyses, including different conditions of seismic activity, are particularly encouraged. Similarly welcome will be the presentation of infrastructures devoted to maintain and further develop our present observational capabilities of earthquake related phenomena also contributing in this way to build a global multi-parametric Earthquakes Observing System (EQuOS) to complement the existing GEOSS initiative.
To this aim this session is not addressed just to seismology and natural hazards scientists but also to geologist, atmospheric sciences and electromagnetism researchers, whose collaboration is particular important for fully understand mechanisms of earthquake preparation and their possible relation with other measurable quantities. For this reason all contributions devoted to the description of genetic models of earthquake’s precursory phenomena are equally welcome. Every 2 years selected papers presented in thsi session will be proposed for publication in a dedicated Special Issue of an international (ISI) scientific journal.

Our capability to provide timely and reliable seismic risk estimates is an essential element towards building a resilient society, through informed decision for risk management. The scientific base of the process of seismic risk mitigation includes various seismic hazard models, developed at different time scales and by different methods, as well as the use of information as complete and reliable as possible about past seismicity.
Some recent large earthquakes caused extensive damage in areas where some models indicated low seismic hazard, leading to an increased demand for criteria to objectively assess how well seismic hazard models are performing. This session aims to tackle theoretical and implementation issues, which are essential for the development of effective mitigation strategies and include:
⇒ methods for comparison of seismic hazard models and their performance evaluation;
⇒ hazard and risk assessment of extreme seismic events;
⇒ long-term evidences about past great earthquakes (including unconventional seismological observations, such as impact on caves, ancient constructions and other deformations evidences);
⇒ earthquake hazard assessment in terms of macro-seismic intensity;
⇒ seismic risk estimation at different time and space scale.
In particular, the session will address concepts, problems, and approaches in assessing hazard related to the earthquakes that “may cause loss of life, injury or other health impacts, property damage, loss of livelihoods and services, social and economic disruption, or environmental damage” (according to UNISDR terminology). The session will include discussions of the pros and cons of deterministic, neo-deterministic, probabilistic, and intensity-based seismic hazard assessments. The latter is of special importance for Europe because of the available large historical information on macro-seismic intensities.
We invite contributions related to: hazard and risk assessment methods and their performance in applications; critical observations and constraints for seismic hazard assessment; verification methods that are suitable to quantify seismic hazard estimates and that can be applied to limited and/or heterogeneous observations (ranging from recent records of ground shaking parameters to past intensity data); seismic hazard and risk monitoring and modeling; and risk communication and mitigation.
The session will provide an opportunity to discuss best practices and share experience gained with different testing methods, including their application in different fields. We hope to highlight both the existing gaps and future research directions that could strengthen the procedures for testing and comparing performance of seismic hazard models.

Seismic techniques are becoming widely used to detect and quantitatively characterise a wide variety of natural processes occurring at the Earth’s surface. These processes include mass movements such as landslides, rock falls, debris flows and lahars; glacial phenomena such as icequakes, glacier calving/serac falls, glacier melt and supra- to sub-glacial hydrology; snow avalanches; water storage and water dynamics phenomena such as water table changes, river flow turbulence and fluvial sediment transport. Where other methods often provide limited spatial and temporal coverage, seismic observations allow recovering sequences of events with high temporal resolution and over large areas. These observational capabilities allow establishing connections with meteorological drivers, and give unprecedented insights on the underlying physics of the various Earth’s surface processes as well as on their interactions (chains of events). These capabilities are also of first interest for real time hazards monitoring and early warning purposes. In particular, seismic monitoring techniques can provide relevant information on the dynamics of flows and unstable slopes, and thus allow for the identification of precursory patterns of hazardous events and timely warning.

This session aims at bringing together scientists who use seismic methods to study Earth surface dynamics. We invite contributions from the field of geomorphology, cryospheric sciences, seismology, natural hazards, volcanology, soil system sciences and hydrology. Theoretical, field based and experimental approaches are highly welcome.

Hydraulic stimulation is a well-operation that aims at enhancing fluid flow at depth. It is applied to exploit unconventional hydrocarbon reservoirs with low permeability and deep geothermal resources. Induced earthquakes frequently accompany the injection of fluids into boreholes potentially leading to damage to infrastructure at the surface and thus generally raising public concern. Damage caused by such events have already terminated Enhanced Geothermal Energy projects in South Korea and Switzerland. Hence, finding safe stimulation methods is critical for future use and public acceptance of geothermal energy projects and potential other forms of energy extraction from the underground. A range of stimulation techniques have been developed to increase the permeability of low-permeable reservoirs, however, our understanding of the processes involved in the formation of hydrofracs and hydroshears and the effectiveness of these operations regarding flow enhancement are still rather limited. A series of successful mine-back experiments have been performed in a range of underground laboratories in Europe. For this session, we invite presentations covering the full range of rock mechanics experiments, underground laboratory testing, and field-scale operations aiming at improving the fundamental understanding of stimulation operations.

Numerical modeling of earthquakes provides new approaches to apprehend the physics of earthquake rupture and the seismic cycle, seismic wave propagation, fault zone evolution and seismic hazard assessment.
Recent advances in numerical algorithms and increasing computational power enable unforeseen precision and multi-physics components in physics-based earthquake simulation but also pose challenges in terms of fully exploiting modern supercomputing infrastructure, realistic parameterization of simulation ingredients and the analysis of large synthetic datasets.
This session aims to bring together modelers and data analysts interested in the physics and computational aspects of earthquake phenomena. We welcome studies focusing on all aspects of the physics of various earthquakes - from slow slip events, fault mechanics and rupture dynamics, to wave propagation and ground motion analysis, to the seismic cycle and inter seismic deformation - and studies which further the state-of-the art in the related computational and numerical aspects.
We further encourage studies linking earthquake source processes to rock mechanics and the laboratory scale.

This session covers the broad field of earthquake source processes, and includes the topics of observing the surface deformation caused by earthquakes, imaging the rupture kinematics and simulating earthquake dynamics using numerical methods, to develop a deeper understanding of earthquake source physics. We also invite presentation that link novel field observations and laboratory experiments to earthquake dynamics, and studies on earthquake scaling properties. Of particular interest are innovative studies on quantifying the uncertainties in earthquake source-parameter estimation.
Within this framework our session also provides a forum to discuss case studies of field observation, kinematic and dynamic source modeling of recent significant earthquakes.

Since 2004, there have been a number of large subduction earthquakes whose unexpected rupture features contributed to the generation of devastating tsunamis. The impact that these events had on human society highlights the need to improve our knowledge of the key mechanisms behind their origin. Advances in these areas have led to progess in our understanding of the most important parameters affecting tsunamigenesis. For example, unexpectedly large slip was observed during the 2011 Tohoku-Oki earthquake, leading to re-investigations of the geology of other subduction zones and the conditions that can lead to large slip at the trench.

In general, the large amount of geophysical data recorded at present has led to new descriptions of faulting and rupture complexity (e.g., spatial and temporal seismic rupture heterogeneity, fault roughness, geometry and sediment type, interseismic coupling, etc.). Rock physicists have proposed new constitutive laws and parameters based on a new generation of laboratory experiments, which simulate close to natural seismic deformation conditions on natural fault samples. Analog modellers now have apparati that simulate multiple seismic cycles with unprecedented realism. These represent a valuable tool for investigating how various boundary conditions (e.g., frictional segmentation, interplate roughness) influence the seismic behavior of subduction megathrusts. In addition, advances in numerical modelling now allow scientists to test how new geophysical observations, e.g. from ocean drilling projects and laboratory analyses, influence subduction zone processes over a range of temporal and spatial scales (i.e., geodynamic, seismic cycling, earthquake rupture, wave propagation modelling).

In light of these advances, this session has a twofold mission: i) to integrate recent results from different fields to foster a comprehensive understanding of the key parameters controlling the physics of large subduction earthquakes over a range of spatial and temporal scales; ii) to individuate how the tsunami hazard analysis can benefit from using a multi-disciplinary approach.

We invite abstracts that enhance interdisciplinary collaboration and integrate observations, rock physics experiments, analog- and numerical modeling, and tsunami hazard.

Recent catastrophic earthquakes have highlighted the importance of advancing seismic hazard models over a wide range of time frames, for example to support more reliable building codes and to track the short-term evolution of seismic sequences. Over the past years, the exponential growth of ground-motion data, short- and long-term forecasting models, hazard model test results, new engineering needs, and progress in research on earthquake predictability and ground-motion processes are creating a strong motivation for the exploration and incorporation of new concepts and methods into the next generation of probabilistic forecasts, both for long-term probabilistic seismic hazard assessment (PSHA), and operational earthquake forecasting. Owing to the important societal impact, any forecasting model has to be scientifically reliable. Prospective modeling is the best way of testing alternate hypotheses and models, and hence advancing our scientific understanding of the processes involved. Pragmatically, prospective testing provides an essential scientific contribution to improving the capacity to manage seismic hazard and risk in a wide range of forecasting time windows, for a broad range of stakeholders, including vulnerable societies. The development of such new and innovative long- and short-term forecasting/hazard models is a necessary but insufficient step: major advances in forecasting and hazard assessment require a solid testing phase that allows for model evaluation and quantifies any increase in forecasting skill over a benchmark model. 

We solicit contributions related to new developments in all aspects of long- and short-term seismic hazard and earthquake forecasting models:
   • Definition of earthquake sources and determination of activity rates and their uncertainty, including assessment of earthquake datasets, calibration of magnitude scales, representation of seismogenic sources and their geological constraints, and the emerging roles of strain and simulation-based earthquake-rupture forecasts.
   • Development of innovative earthquake forecasting models with forecast horizons of days to decades.
   • Estimation of strong ground motions and their uncertainty, development of new ground-motion models, assessment of site effects, the consideration of new parameters to characterize the intensity of shaking, and potential insights and uses of physics-based simulations of ground shaking. 
   • Testing and evaluation of hazard and earthquake forecasting models including statistical tests of 
activity rates, earthquake occurrence, calibration of ground-motion models, hazard-model parameterization and implementation, sensitivity analyses of key parameters and results, as well as the development of innovative testing procedures.
   • Case studies of PSHA from Europe and around the globe. 
   • Model building processes and related uncertainties, formal elicitation of expert opinion and its consequences for the levels of knowledge or belief, and comprehensive treatment of aleatory and epistemic uncertainties.
   • Contributions related to the ongoing update of the Harmonized European Seismic Hazard model and the emerging EPOS infrastructure on hazard and risk.
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The use of fibre technologies for geophysical applications is expanding since few years. The design of highly sensitive sensors, such as rotational seismometers or strainmeters is one approach. In addition, initiatives such as SMART cables systems aim at piggy-backing environmental sensors onto submarine repeater units in order to improve sensor coverage across the oceans The use the fibre itself as a distribution of sensors for temperature or strain distributed sensing is an alternative. The vast majority of all telecommunications data (99%) transit through submarine and land-based fibre-optic cables. As the need for larger bandwidth and more rapid transmission has increased, so do the global networks of cables encircling the Earth. They now cover even remote regions of most continents and oceans. There have been significant advances in cable design and manufacturing technology, as well as cable deployment procedures. In very recent years there have been significant breakthroughs, applying techniques developed to interrogate the cables at very high precision over very large distances. For example, laser reflectometry using DAS (Distributed Acoustic Sensing) on both dedicated experimental and commercial fiber optic cables onshore and in submarine environment have successfully detected a variety of seismic sources (including ambient noise (microseism), local and teleseismic earthquakes, volcanic events, etc.). Other laser reflectometry techniques have long been used for monitoring of large-scale engineering infrastructures (dams, tunnels, bridges, pipelines, boreholes, etc.) and recently have been applied to natural hazard studies on land (monitoring of landslides or karst sinkholes) and have broader applications to the study of faults for instance. We welcome contributions that involve the application of fiber-optic cables or sensors in seismology, geodesy, geophysics, natural hazards, etc. from the laboratory to large-scale field tests.
We are delighted to have an Invited Speaker: Giuseppe Marra

Induced and triggered seismicity are common phenomena associated with sub-surface exploration and remote seismic events, respectively, and have been related to hydrocarbon extraction, hydraulic fracturing, geothermal exploitation, open-pit crater formation and underground mining operations, CO2 sequestration, and filling of new water reservoirs. Public awareness and concern of induced seismicity has become ubiquitous in locations where subsurface exploration and storage is carried out in close proximity to communities. Of particular concerns are massive fluid injections for hydro-fracturing to increase subsurface permeability as well as long-term injection in disposal wells. These concerns have led to regulations to passively monitor induced seismicity and consequently to a wealth of continuous seismic data. In contrast to the increase in data volume, our understanding of the relationship between exploitation techniques and induced seismicity as well as earthquake-earthquake interactions is still limited. New processing methods to analyze data and quantitative models to improve our understanding of the causal relationship between exploitation and seismicity have been developped. The current session is intended to provide a platform to present the latest research, field studies, theoretical and modelling aspects as well as methods for seismic hazard analysis related to induced and triggered seismicity. Topics to be presented include spatio-temporal variations of physical parameters in reservoirs and natural environments including stress and pressure changes, spatial-temporal patterns of seismicity, source mechanisms of micro- or larger-scale seismicity, mechanisms for induced events and seismic interaction, as well as, fracture-induced anisotropy. Contributions are sought from fundamental and applied research covering the fields of oil and gas operations including hydro-fracturing, geothermal exploitation particularly related to enhanced geothermal systems, open pit and underground mining, CO2 storage, and other fields such as volcano-seismology where induced and triggered seismic activity is observed.

Many new high quality and high resolution geophysical and geological data had been acquired in the past years that need to be updated, re-analysed and re-interpreted in the light of our present knowledge in subductions processes. Moreover it is needed to better clarify the temporal and spatial evolution of those processes in order to much precise our geodynamic ideas of mountain building, subduction, transition of collision to subduction, or transition of subduction to collision.
Among other global places, the zone from Japan, Taiwan to the Philippines is a key area to study such subduction/collision transition due to the rapid convergence between Eurasian and Philippine Sea plates. There are geodynamic inversion of the east dipping Manila oceanic subduction, that evolves northward, first, into a Continental Subduction (also called Collision) onshore Taiwan, then secondly, east of Taiwan, into the north dipping Ryukyu arc/continent subduction. Due to the so rapid Plates shortening rate (10cm.y-1), those active Oceanic to Continental Subductions processes in Taiwan creates 1/8 of the annual seismicity in the World !
There are other places in the World active or not, that should also be taken into careful consideration in order to reveal and lead us to better understand new tectonic processes (e.g.: Alpes, Pyrénées, Cascades and so on).
To conclude in this EGU session, we aim to update the existing geodynamic state of the art of the oceanic to continental subductions processes after so numerous data that had been collected recently and all the works that had been done on this subject. Therefore this EGU Session should help us to much better understand the tectonics related to plate, plate collision and the transition between the subduction and collision.

The study of active faults and deformation of the Earth's surface has made, and continues to make, significant contributions to our understanding of earthquakes and the assessment of seismic related hazard.
Active faulting may form and deform the Earth's surface so that records are documented in young sediments and in the landscape. Field studies of recent earthquake ruptures help not only constraining earthquake source parameters but also the identification of previously unknown active structures. The insights gleaned from recent earthquakes can be applied to study past earthquakes. Paleoseismology and related disciplines such as paleogeodesy and paleotsunami investigations still are the primary tools to establish earthquake records that are long enough to determine recurrence intervals and long-term deformation rates for active faults. Multidisciplinary data sets accumulated over the years have brought unprecedented constraints on the size and timing of past earthquakes, and allow deciphering shorter-term variations in fault slip rates or seismic activity rates, as well as the interaction of single faults within fault systems. Based on the this rich, but very heterogeneous knowledge of seismogenic faults, a variety of approaches have been developed to tranfer earthquake-fault geology into fault models suitable for probabilistic SHA. This session thus aims at linking field geologists, crustal deformation modellers, fault modellers, and seismic hazard practitioners.

In this session, we welcome contributions describing and critically discussing different approaches to study active faults. We are particularly interested in studies applying new and innovative methodological or multidisciplinary approaches. We hope to assemble a broad program bringing together studies dealing with on-land, lake or offshore environments, and applying a variety of methods such as traditional paleoseismic trenching, high-resolution coring, geophysical imaging, tectonic geomorphology, and remote sensing, as well as the application of earthquake geology in seismic hazard assessments. In addition, we encourage contributors describing how to translate fault data or catalogue data into fault models for SHA , and how to account for faults or catalogue issues.

Our first-order understanding of earthquake cycles is limited by our ability to detect and interpret natural phenomena or their relict signatures on faults. However, such observations allow us to define fundamental hypotheses that can be tested by way of experiments and models, ultimately yielding deeper insights into mechanics of faulting in nature. Inter-, co-, and post-seismic deformation can be documented geodetically, but the sparseness of the data and its large spatial and temporal variability do not sufficiently resolve their driving mechanisms. Laboratory experiments under controlled conditions can narrow down the possibilities, while numerical modelling helps extrapolating these results back to natural conditions. Thus, integrated approaches to bridge long-term tectonics and the earthquake cycle that combine observation, interpretation, experimentation, and finally, physical or numerical modelling, are key for our understanding of the deformation behaviour of complex fault systems.

This session seeks contributions toward an integrated perspective on the earthquake cycle that span a wide range of observations, methodologies, and modelling over a variety of spatial and temporal scales. Presentations can cover brittle and ductile deformation, from microstructures to mantle rheology and with applications to earthquake mechanics, geodynamics, geodesy, geohazards, and more. Specific questions include: How do long-term crustal and lithospheric deformation affect short-term seismicity and earthquake cycle behaviour? What is the long-term topographic signature of the earthquake? What are the relative contributions of rheology and geometry for seismic and aseismic slip? What are the roles of on- and off-fault deformation in shaping the landscape and partitioning seismic and aseismic energy dissipation? We welcome submissions by early-career scientists in particular.

— Invited speaker: Luc L Lavier, Jackson School of Geosciences | The University of Texas at Austin

Earthquakes that occur within regions of slow lithospheric deformation (low-strain regions) are inherently difficult to study. The long interval between earthquakes, coupled with natural and anthropogenic modification, limit preservation of paleoearthquakes in the landscape. Low deformation rates push the limits of modern geodetic observation techniques. The short instrumental record challenges extrapolation of small earthquake recurrence based on modern seismological measurement to characterize the probability of larger, more damaging earthquakes. Characterizing the earthquake cycle in low-strain settings is further compounded by temporal clustering of earthquakes, punctuated by long periods of quiescence (e.g. non-steady recurrence intervals). However, earthquakes in slowly deforming regions can reach high magnitudes and pose significant risk to populations.

This session seeks to integrate paleoseismic, geomorphic, geodetic, geophysical, and seismologic datasets to provide a comprehensive understanding of the earthquake cycle in low-strain regions. This session will draw upon recent advances in high-resolution topography, geochronology, satellite geodesy techniques, subsurface imaging techniques, longer seismological records, high-density geophysical networks and unprecedented computational power to explore the driving mechanisms for earthquakes in low-strain settings. We welcome contributions that (1) present new observations that place constraints on earthquake occurrence in low-strain regions, (2) explore patterns of stable or temporally varying earthquake recurrence, and (3) provide insight into the mechanisms that control earthquakes in regions of slow deformation via observation and/or modeling.

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

The 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 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/

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
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.

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.

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.

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.

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.

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 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).

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.

Remote sensing and Earth Observations (EO) are used increasingly in the different phases of the risk management and in development cooperation, due to the challenges posed by contemporary issues such as climate change, population pressure and increasingly complex social interactions. EO-based applications have a number of advantages over traditional fieldwork expeditions including safety, the provision a synoptic view of the region of interest, the availability of data extending back several years and, in many cases, cost savings. Fortunately, the advent of new, more powerful sensors and more finely tuned detection algorithms provide the opportunity to image, assess and quantify natural hazards, their consequences, and vulnerable regions, more comprehensively than ever before.
For these reasons, the civil protections, the development agencies and space agencies have now inserted permanently into their programs applications of EO data to risk management. In particular, the Committee on Earth Observation Satellites (CEOS) has a permanent working group on Disasters that supports and promotes the use of EO data for Disaster Risk management (DRM). During the preparedness and prevention phase EO revealed, especially in data scarce environments, fundamental for hazard, vulnerability and risk mapping. EO data intervenes both in the emergency forecast and early emergency response, thanks to the potential of rapid mapping. EO data is also increasingly being used for mapping useful information for planning interventions in the recovery phase, giving to managers and emergency officials a wealth of time-continuous information for assessment and analysis of natural hazards, from small to large regions around the globe. In this framework, CEOS has been working from several years on disasters management related to natural hazards (e.g., volcanic, seismic, landslide and flooding ones), including pilots, demonstrators, recovery observatory concepts, Geohazard Supersites and Natural Laboratory (GSNL) initiatives and multi-hazard management projects.

The session is dedicated to multidisciplinary contributions especially focused on the demonstration of the benefit of the use of EO for the risk management, with an operational user-oriented perspective.
The research presented might focus on:
- Addressed value of EO data in risk/hazard forecasting models (observation of possible precursory events and evaluation of potential predictive capabilities)
- Innovative applications of EO data for rapid mapping.
- Innovative applications of EO data for hazard, vulnerability and risk mapping.
- Innovative applications of EO data for the post-disaster recovery phase.
- Innovative applications in support to disaster risk reduction strategies (eg. landscape planning).
- Development of tools and platforms for assessment and validation of hazard/risk models

The use of different types of remote sensing (e.g. thermal, visual, radar, laser, and/or the fusion of these) might be considered, with an evaluation of their respective pros and cons. Evaluation of current sensors, data capabilities and algorithms will be welcomed, as will suggestions for future sensor considerations, algorithm developments and opportunities for emergency management agency buy-in.
Early stage researchers are strongly encouraged to present their research. Moreover, contributions from international cooperation, such as CEOS and GEO initiatives, are welcome.

The availability of high spatial resolution Synthetic Aperture Radar (SAR) data, the advances in SAR processing techniques (e.g. interferometric, polarimetric, and tomographic processing), and the fusion of SAR with optical imagery as well as geophysical modelling allow ever increasing use of Imaging Geodesy using SAR/InSAR as a geodetic method of choice for earth system monitoring and investigating geohazard, geodynamic and engineering processes. In particular, the exploitation of data from new generation SAR missions such as Sentinel-1 that provide near real-time measurements of deformation and changes in land cover/use has improved significantly our capabilities to understand natural and anthropogenic hazards and then helped us mitigate their impacts. The development of high-resolution X-band SAR sensors aboard missions such as Italian COSMO-SkyMed (CSK) and German TerraSAR-X (TSX) has also opened new opportunities over the last decade for very high-resolution radar imaging from space with centimetre geometric accuracy for detailed analysis of a variety of processes in the areas of the biosphere, geosphere, cryosphere and hydrosphere. All scientists exploiting radar data from spaceborne, airborne and/or ground-based SAR sensors are cordially invited to contribute to this session. The main objective of the session is to present and discuss the progress, state-of-the-art and future perspectives in scientific exploitation of SAR data, mitigating atmospheric effects and error sources, cloud computing, machine learning and big data analysis, and interpretation methods of results obtained from SAR data for various types of disasters and engineering applications such as earthquakes, volcanoes, landslides and erosion, infrastructure instability and anthropogenic activities in urban areas. Contributions addressing scientific applications of SAR/InSAR data in biosphere, cryosphere, and hydrosphere are also welcome.

World population growth combined with continuous climate changes increase the possibility of the human settles to be affected by landslides, earthquakes, floods and others natural and anthropogenic geohazards. As consequences, human settlements, structures and infrastructures can suffer important damage, casualties and injuries, and an enormous amount of resources are needed to restore direct and indirect costs. Furthermore, the social impact and the loss of cultural and historical heritage must be considered.
The International Disaster Database created by the Centre for Research on the Epidemiology of Disasters (CRED) states that more than 14,000 worldwide relevant natural disasters occurred during the last century, causing casualties or requiring of international assistance.
For this reason, the investigation, characterization and monitoring of geo-hazardous phenomena play a fundamental role in order to improve the knowledge for avoiding further recurrences with additional social, human and economic losses. The use of Earth Observation (EO) techniques for monitoring and characterizing geohazards is a well-known way to study these phenomena. The application of EO methods in this field has risen exponentially in the last decades yet nowadays is constantly evolving.
Remote sensing approaches allow to efficiently retrieve relevant information on geological processes at regional scale to investigate, characterize, monitor and model, as well as to prevent, geohazards. Satellites constellations, air and ground platforms equipped with different sensors, (e.g. optical camera, radar or LiDAR), coupled with advanced processing techniques and algorithms are one of the best ways to investigate geohazards. The possibility to combine different types of data allows to perform multi-sensor and multi-temporal analyses. In this way, the wide area coverage capabilities combined with high accuracy and precision play an important role in the widespread use for different applications.
Submissions are encouraged to cover a broad range of topics on the various applications of remote sensing techniques, which may include, but are not limited to, the following topics: i) innovative applications and methods on remote sensing, ii) significant cases of study, iii) applications and models concerning the use of satellite, iv) air and ground platform taking advantage of the use of different sensors for investigating a broad range of topic (e.g. landslide, subsidence, damage assessment, infrastructure stability).

The use of Remotely Piloted Aircraft Systems (RPAS) for geosciences applications has strongly increased in last years. Nowadays the massive diffusion of mini- and micro-RPAS is becoming a valuable alternative to the traditional monitoring and surveying applications, opening new interesting viewpoints. The advantages of the use of RPAS are particularly important in areas characterized by hazardous natural processes, where the acquisition of high resolution remotely sensed data could be a powerful instrument to quickly assess the damages and plan effective rescues without any risk for operators.
In general, the primary goal of these systems is the collection of different data (e.g., images, LiDAR point clouds, gas or radioactivity concentrations, etc.) and the delivery of various products (e.g., 3D models, hazard maps, high-resolution orthoimages, etc.).
The possible use of RPAS has promising perspectives not only for natural hazards, but also in the different field of geosciences, to support a high-resolution geological or geomorphological mapping, or to study the evolution of active processes. The high repeatability of RPAS flight and their limited costs allows the multi-temporal analysis of a studied area. However, methodologies, best practices, advantages and limitations of this kind of applications are yet unclear and/or poorly shared by the scientific community.
This session aims at exploring the open research issues and possible applications of RPAS in geosciences, collecting experiences, case studies, and results, as well as define methodologies and best practices for their practical use. The session will concern the contributions aiming at: i) describing the development of new methods for the acquisition and processing of RPAS dataset, ii) introducing the use of new sensors developed or adapted to RPAS, iii) reporting new data processing methods related to image or point cloud segmentation and classification and iv) presenting original case studies that can be considered an excellent example for the scientific community.