Large slope instabilities have been recognised in mountainous areas in different lithological and geological domains, and on other planets. Slow to extremely 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 debated:
- regional distribution and relevance;
- presence, distribution and significance of phenomena on other planets;
- triggering and controlling factors;
- dating of initial movements and reactivation episodes;
- style and state of past and present activity;
- passive and/or active control by structural-tectonic elements;
- hydrological boundary conditions;
- possible evolution and modelling;
- assessment of related hazard;
- influence of anthropogenic factors and effects on structures;
- role on the erosional and sediment yield regime in drainage catchments and mountain belts;
- technologies for monitoring and warning systems, and the interpretation of monitoring data.
Study of these instabilities involves geology, geomorphology, geomechanics, hydro-geochemistry, and geophysics. For landslides on other planets a few of these approaches can be adopted making more difficult the interpretation of the phenomena, the identification of triggerings and controlling factors.
Trenching and drilling can be used for material characterization, recognition of activity episodes, which can be combined with monitoring data for establishing of warning thresholds and systems.
Geophysical survey methods can describe both the geometrical and geomechanical characteristics of the unstable mass. Dating techniques can be applied to determine the age of movements. Modelling can be applied to evaluate instability and failure, triggering (rainfall, seismicity, volcanic eruption, deglaciation), failure propagation, collapse (rock avalanches, debris avalanches and flows), and secondary failures (rockfall, debris flows).
Different hydraulic and hydrologic boundary conditions and hydrochemistry are involved, both at failure and during reactivations. The impacts of such instabilities on structures and human activities can be substantial and of a variety of forms. 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.

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.

This session aims to discuss precipitation-induced hydrological and geomorphological processes such as different types of landslides on local and regional scale in natural and human-modified landscapes. Landslides and mobilized in-stream sediment represent an important source of hazard for economic activities, infrastructures and population living on the slopes and in adjacent lowland areas.
Precipitation-induced hydro-geomorphological processes can deliver large volumes of sediment to the stream network and are often associated with the occurrence of shallow landslides and channelized debris flows. 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 and debris flows. However, incorporation of hydrological process knowledge in these processes, such as water-rock interaction, water storage, dynamic preferential flows or the influence of frost conditions to name a few, still lags behind. Detailed monitoring, analysis and modelling of hydro-geomorphological processes are required to improve our understanding and prediction of the spatio-temporal patterns of the hydro-geomorphological processes.
The purpose of this session is to gather contributions aimed at understanding the influence of environmental and anthropic factors on the hydro-geomorphological response of natural and human-modified slopes and catchments. 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, debris flows and to large scale deep-seated slope deformation. The session wishes to represent an opportunity for sharing and exchanging knowledge, approaches and achievements between experts and young scientists that may be useful in scheduling proper landslide risk prevention and mitigation strategies in human-modified catchments.

Debris flows are among the most dangerous natural hazards that threaten people and infrastructures in both mountainous and volcanic areas. The study of the initiation and of the dynamics of debris flows, along with the characterization of the associated erosion/deposition processes, is of paramount importance for hazard assessment, land-use planning and design of mitigation measures, including early warning systems.
A growing number of scientists with diverse backgrounds are studying debris flows and lahars. The difficulties in measuring parameters related to their initiation and propagation have progressively prompted research into a wide variety of laboratory experiments and monitoring studies. However, there is a need of improving the quality of instrumental observations that would provide knowledge for more accurate hazards maps and modeling. Nowadays, the combination of distributed sensor networks and remote sensing techniques represents a unique opportunity to gather direct observations of debris flows to better constrain their physical properties.
Scientists working in the field of debris flows are invited to present their recent advancements. In addition, contributions from practitioners and decision makers are also welcome. Topics of the session include: field studies and documentation, mechanics of debris-flow initiation and propagation, laboratory experiments, modeling, monitoring, hazard and risk assessment and mapping, early warning, and alarm systems.

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.

Public information:
EGU Session NH3.7

Welcome to the Session NH3.7 on Space and Time Forecast of Landslides

The chat session will proceed by maintaining the original order provided by the session program. However, only the presentations with actually uploaded material will be listed in the session chat list.

Authors will be introduced In groups of 3 and will have 1-2 minutes each, in sequence, to briefly introduce their work by copy-pasting some brief sentences that summarise the research

Afterwards, there will be 5-6 minutes devoted to questions by the audience to the 3 authors. Since Q&A will concern 3 different presentations at the same time, we ask both presenters and questioners to always state who is the recipient of each question and each answer, to avoid confusion.
For example, a correct question style could be: “@MarkSmith: could you please say something more on the landslide database?”

Conveners, acting as session chairs and moderators, will signal when question time is over. They will also collect and resubmit possible questions that have gone unanswered during the chat, if possible.

After each round of 3 author presentations and Q&A, the conveners will introduce the next three speakers.

At the end of the list, if additional time remains, the conveners will open a final discussion on the general topics of the session and on integrated questions transversal to 2 or more presentations.

We remember that participants are encouraged to keep discussing mutual interests on research topics also after the Session, by emailing each other.
Please note that in the Session Displays page, each abstract has a link icon where it is possible to directly email the abstract main author.

Best
FC, XF, FG, BT

This session covers an overview of the progress and new scientific approaches for investigating landslides using state-of-the-art techniques such as: Earth Observation (EO), close-range Remote Sensing techniques (RS) and Geophysical Surveying (GS).

A series of remarkable technological progresses are driven new scientific opportunities to better understand landslide dynamics worldwide, including integrated information about rheological properties, water content, rate of deformation and time-varying changes of these parameters through seasonal changes and/or progressive slope damage.

This session welcomes innovative contributions and lessons learned from significant case studies and/or original methods aiming to increase our capability to detect, model and predict landslide processes at different scales, from site specific to regional studies, and over multiple dimensions (e.g. 2D, 3D and 4D).

A special emphasis is expected not only on the particularities of data collection from different platforms (e.g. satellite, aerial, UAV, Ground Based...) and locations (e.g. surface- and borehole-based geophysics) but also on new solutions for digesting and interpreting datasets of high spatiotemporal resolution, landslide characterization, monitoring, modelling, as well as their integration on real-time EWS, rapid mapping and other prevention and protection initiatives. Examples of previous submissions include using one or more of the following techniques: 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 DInSAR, GPS surveying, Seismic Reflection, Surface Waves Analysis, Geophysical Tomography (seismic and electrical), Seismic Ambient Vibrations, Acoustic Emissions, Electro-Magnetic surveys, low-cost sensors, commercial use of small satellites, Multi-Spectral images, etc. 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 very welcomed.

GUEST SPEAKER: this year, we invited professor Jonathan Chambers, team leader of the geophysical tomography cluster at the British Geological Survey (BGS).

The global increase in damaging landslide events is raising the attention of governments, practitioners and scientists to develop functional, reliable and (when possible) low cost monitoring strategies. Several case studies have demonstrated how a well-planned monitoring system of landslides is of fundamental importance for long and short-term risk reduction.
Today, the temporal evolution of a landslide is addressed in several ways, encompassing classical and more complex in situ measurements or remotely sensed data acquired from satellite and aerial platforms. All these techniques are adopted for the same final scope: measure landslide motion over time, trying to forecast its future evolution or at least to reconstruct its recent past. Real time, near-real time and deferred time strategies can be profitably used for landslide monitoring, depending on the type of phenomenon, the selected monitoring tool and the acceptable level of risk.
The session follows the general objectives of the International Consortium on Landslides, namely: (i) promote landslide research for the benefit of society, (ii) integrate geosciences and technology within the cultural and social contexts to evaluate landslide risk, and (iii) combine and coordinate international expertise.
Considering these key conceptual drivers, we aim to present successful monitoring experiences worldwide based on both in situ and/or remotely sensed data. The integration and synergic use of different techniques is welcome, as well as newly developed tools or data analysis approaches (focusing on big data management). We expect case studies in which multi-temporal and multi-platform monitoring data are exploited for risk management and Civil Protection aims with positive effects in social and economic terms.

In many parts of the world, landslide phenomena are a direct response to rapid environmental changes caused by global warming, human influences or other natural or technological hazards. The development of methods and strategies to evaluate hazard and risk posed by different types of landslides with different magnitudes in different environments has significantly progressed in the last decades due to rapid advance of computational and monitoring technologies. However, prognostic hazard and risk evaluations are highly challenged by the fact that local and regional environmental and meteorological conditions are subjected to rapid changes due to global warming and its consequences, modifying the local terrain susceptibility to landslides. Additionally, global change leads to significant changes in patterns of objects-at-risk due to population changes and concurring infrastructural developments.
This session aims to collect papers dealing with the advancement of methods and strategies for the prognostic spatio-temporal development of landslide hazard and risk scenarios and potentials in times of rapid global environmental change. Contributions dealing with the preparation and use of event-based landslide inventories for landslide hazard scenario assessments are welcomed as well as papers describing new advancements in process-oriented techniques for landslide hazard modelling at different spatial scales. Of particular interest are contributions concerned with the assessment of changing patterns of landslide-related risk posed to developing population and infrastructure in times of rapid environmental change.

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.

Climate change (CC) is expected affecting weather forcing regulating the triggering, reactivation, and severity of slope failures and soil erosion. In this view, the influence of CC can be different according to the area, the time horizon of interest and to the specific trends of weather variables. Similarly, land use/cover change can play a pivotal role in exacerbating or reducing such hazards.
Thus, the overall impacts depend on the region, spatial scale, time frame and socio-economic context addressed. However, even the simple identification of the weather patterns regulating the occurrence of such phenomena represents a not trivial issue, also assuming steady conditions, due to the crucial role played by geomorphological details. To support hazards’ monitoring, predictions and projections, last-generation and updated datasets with high spatio-temporal resolution and quality - like those from the Copernicus Services’ Portals - are useful to feed models, big-data analytics and indicators’ frameworks enabling timely, robust and efficient decision making.
The Session aims at presenting studies concerning ongoing to future landslide dynamics and soil erosion hazards across different geographical contexts and scales (from slope to regional, to global scale) including analyses of historical records and related climate variables, or modeling approaches driven by future climate exploiting downscaled output of climate projections. Studies assessing variations in severity, frequency and/or timing of events and consequent risks are valuable. Finally, tested or designed adaptation strategies can be discussed.

Snow avalanches range among the most prominent natural hazards which threaten mountain communities worldwide. Snow avalanche formation is a complex critical phenomenon which starts with a failure processes at the scale of snow crystals and ends with the release of a large volume of snow at a scale of up to several hundred meters. The practical application of avalanche formation is avalanche forecasting, requiring a thorough understanding of the physical and mechanical properties of snow as well as the influence of meteorological boundary conditions (e.g. precipitation, wind and radiation).

This session aims to improve our understanding of avalanche formation processes and to foster the application to avalanche forecasting. We therefore welcome contributions from novel field, laboratory and numerical studies on topics including, but not limited to, the mechanical properties of snow, snow cover simulations, snow instability assessment, meteorological driving factors including drifting and blowing snow, spatial variability, avalanche release mechanics, remote avalanche detection and avalanche forecasting. While the main focus of this session is on avalanche formation, detection and forecasting, it is closely linked to session ‘CR3. Snow avalanche dynamics: from basic physical knowledge to mitigation strategies’, which addresses avalanche dynamics, risk assessment and mitigation strategies.

This session is devoted to the dynamics of dense and powder snow avalanches and their accompanying transitional regimes. One focus is their interaction with, and impact on, vulnerable elements, such as buildings, protection dams, forests, and roads. We welcome novel experimental and computational contributions including, but not limited to the topics of avalanche dynamics and related processes, physical vulnerability of structures impacted by snow avalanches, avalanche hazard zoning and avalanche mitigation strategies. These include field, laboratory and numerical studies that rely on new methods and techniques (radars, drone, satellite, etc.) as well as practical case studies.

Furthermore, we solicit novel contributions from the area of granular flows, viscoplastic flows, density currents, turbulent flows, as well as contributions from other gravitational mass flows communities, which can improve our understanding and modeling of snow avalanche propagation and their interaction with natural or man-made structures.

While the main focus of this session is on snow avalanche dynamics from basic knowledge to mitigation strategies, it is closely linked to session CR3.4 entitled "Snow avalanche formation: from snow mechanics to avalanche detection" which addresses avalanche formation, detection and forecasting.

Physical erosion and chemical weathering dominate the evolution of surface and subterranean mountain landscapes over a wide range of temporal and spatial scales. Signals from processes such as glacial and periglacial erosion, chemical and mechanical weathering, rockfall, debris flow, and hillslope failure are preserved in downstream patterns of river and/or valley aggradation and incision as well as in the development of karst systems and their sediment deposits. These processes react to a wide spectrum of external and internal forcings (e.g. climatic variability, tectonic activity, spatial patterns of vegetation or sudden internal failure) often making it difficult to relate these records back to specific causal mechanisms.

Measuring the dynamical interplay of erosion, weathering and sedimentation as well as quantifying the rates and fluxes associated with the evolution of mountainous landscapes, is a crucial but challenging component of source-to-sink sediment research. Many of these processes also pose serious threats to the biosphere, mountain settlements and infrastructure. Understanding and quantifying these processes from both a societal and engineering point of view will lead to better preparation and responses to such threats.

We welcome contributions that (1) investigate the processes of production, mobilisation, transport, and deposition of sediment in mountain landscapes, (2) study the development of cave systems and their sedimentary archive in relation to external base-level conditions and internal dynamics (3) explore feedbacks between erosion and weathering due to natural and anthropogenic forcings, (4) address the role these processes play in the larger source-to-sink context, and (5) consider how these processes contribute to natural hazards specific to mountain landscapes. We invite presentations that employ observational, analytical or modelling approaches in mountain environments across a variety of temporal and spatial scales. We particularly encourage early career scientists to apply for this session.

Public information:
Block 1 schedule:

14:00-14:10: A bit of time to explore the displays.
14:10: Oliver Francis D1106 EGU2020-891 The fate of sediment after a large earthquake
14:20: Rachel Glade (solicited) D1107 EGU2020-12761 River canyon evolution governed by autogenic channel-hillslope feedbacks
14:35: Benjamin Campforts D1108 EGU2020-13064 To slide or not to slide: explicit integration of landslides and sediment dynamics in a landscape evolution model
14:45: Philippe Vernant D1109 EGU2020-9099 First quantitative evidences of ghost-rock karstification controlling regional karst geometry
14:55: Robert Hilton D1112 EGU2020-5624 A shifting view of erosion and the carbon cycle
15:05: Stephanie Olen D1114 EGU2020-5939 Synthetic aperture radar coherence as a proxy for geomorphic activity
15:15: Eric Deal D1115 EGU2020-5510 Analytical long-profile models of coupled glacier-fluvial systems
15:25: Anna Masseroli D1119 EGU2020-749 Differentiation among geomorphological processes in a mountain hydrographic basin by means of soils analyses
15:35: Alex Beer D1122 EGU2020-12980 Bedrock Topographic Evolution from Rockfall Erosion

Block 2 schedule:
16:20: Sharon Pittau D1123 EGU2020-10391 A multi-temporal inventory for constraining earthflow source-to-sink pathways in the Sillaro River basin, Northern Apennines
16:30: Emma Graf D1126 EGU2020-455 Where does all the gravel go? Tracking landslide sediment from the 2015 Gorkha earthquake along the Kosi River, Nepal
16:40: Paul Krenn D1127 EGU2020-13255 Analysing the impacts of extreme precipitation events on geomorphic systems in torrential catchments; a comparative study from Upper Styria, Austria
16:50: Benjamin Purinton D1129 EGU2020-3943 Multiband (X, C, L) radar amplitude analysis for a mixed sand- and gravel-bed river in the eastern central Andes
17:00: Jinyu Zhang D1131 EGU2020-12497 Reconstructing aggradation and incision of the Lancang River (Upper Mekong) at Yunlong reach, southeast Tibet
17:10: Frank Lehmkuhl D1132 EGU2020-3893 Quaternary paleoenvironmental change preserved in alluvial fans systems in semiarid to arid mountain areas: Examples from western Mongolia, western USA, and the Chilean Andes
17:20: Erica Erlanger D1134 EGU2020-12043 Partitioning the denudation flux between silicate and carbonate physical erosion and chemical weathering in the Northern Apennines
17:30: Tim Jesper Suhrhoff D1136 EGU2020-18195 Weathering signals in Lake Baikal and its tributaries
17:40: Maarten Lupker D1137 EGU2020-4480 Chemical weathering pathways in the central Himalaya – new constraints from DI14C and δ34S
17:50: Luca Pisani D1140 EGU2020-3935 Karst porosity development in layered and fractured carbonates: field evidences of structural control on sulfuric acid speleogenesis (Majella Massif, Italy)

Geomorphometry and geomorphological mapping are important tools used for understanding landscape processes and dynamics on Earth and other planetary bodies. Recent rapid growth of technology and advances in data collection methods has made available vast quantities of geospatial data for such morphometric analysis and mapping, with the geospatial data offering unprecedented spatio-temporal range, density, and resolution. This explosion in the availability of geospatial data opens up considerable possibilities for morphometric analysis and mapping (e.g. for recognising new landforms and processes), but it also presents new challenges in terms of data processing and analysis.

This inter-disciplinary session on geomorphometry and landform mapping aims to bridge the gap between process-focused research fields and the technical domain where geospatial products and analytical methods are developed. The increasing availability of a wide range of geospatial datasets requires the continued development of new tools and analytical approaches as well as landform/landscape classifications. However, a potential lack of communication across disciplines results in efforts to be mainly focused on problems within individual fields. We aim 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 geospatial data that is now available.

We welcome perspectives on geomorphometry and landform mapping from ANY discipline (e.g. geomorphology, planetary science, natural hazard assessment, computer science, remote sensing). This session aims to showcase both technical and applied studies, and we welcome contributions that present (a) new techniques for collecting or deriving geospatial data products, (b) novel tools for analysing geospatial data and extracting innovative geomorphometric variables, (c) mapping and/or morphometric analysis of specific landforms as well as whole landscapes, and (d) mapping and/or morphometric analysis of newly available geospatial datasets. Contributions that demonstrate multi-method or inter-disciplinary approaches are particularly encouraged. We also actively encourage contributors to present tools/methods that are “in development”.

Rock deformation at different stress levels in the brittle regime and across the brittle-ductile transition is controlled by damage processes occurring on different spatial scales, from grain scale to fractured rock masse. These lead to a progressive increase of micro- and meso-crack intensity in the rock matrix and to the growth of inherited macro-fractures at rock mass scale. Coalescence of these fractures forms large-scale structures such as brittle fault zones and deep-seated rock slide shear zones. Diffuse or localized rock damage have a primary influence on rock properties (strength, elastic moduli, hydraulic and electric properties) and their evolution across multiple temporal scales spanning from geological times to highly dynamic phenomena as earthquakes, volcanic eruptions and landslides. In subcritical stress conditions, damage accumulation results in brittle creep processes key to the long-term evolution of geophysical, geomorphological and geo-engineering systems.

Damage and progressive failure processes must be considered to understand the time-dependent hydro-mechanical behaviour of faults (e.g. stick-slip vs asesismic creep), volcanic systems and slopes (e.g. slow rock slope deformation vs catastrophic rock slides), as well as the response of rock masses to stress perturbations induced by artificial excavations (tunnels, mines) and static or dynamic loadings. At the same time, damage processes control the brittle behaviour of the upper crust and are strongly influenced by intrinsic rock properties (strength, fabric, porosity, anisotropy), geological structures and their inherited damage, as well as by the evolving pressure-temperature with increasing depth and by fluid pressure, transport properties and chemistry. However, many complex relationships between these factors and rock damage are yet to be understood.

In this session we will bring together researchers from different communities interested in a better understanding of rock damage processes and consequence. We welcome innovative contributions on experimental studies (both in the laboratory and in situ), continuum / micromechanical analytical and numerical modelling, and applications to fault zones, reservoirs, slope instability and landscape evolution, and engineering applications. Studies adopting novel approaches and combined methodologies are particularly welcome.

Invited speakers:
- Brian Collins  (U.S. Geological Survey)
-  Jérôme Aubry  (Ecole Normale Supérieure de Paris)