This session will focus on recent and upcoming advances in satellite remote sensing of the global cryosphere. We welcome presentations providing new insights into cryospheric processes in the broadest sense, ranging from ice sheets, glaciers, snow cover and snow properties, frozen soil and sea ice to extraterrestrial glaciology. While the advent of remote sensing has revolutionized the field of glaciology, a vast reservoir of potential remains to be unlocked by using these observations in concert with other data sets. We particularly encourage presentations discussing multi-platform data merging, integration of GIS and ground validation data, integration of remote sensing data into earth system models, as well as cloud computing and processing of super large data sets. We also encourage contributions focusing on historic satellite data re-analysis, novel processing approaches for upcoming satellite missions, and presentations outlining pathways to next-generation satellite missions for the coming decades.
We are committed to a well-balanced session.

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Invited Speaker is Christian Hauck (University of Fribourg) with the title:
'Geophysical monitoring techniques to observe Alpine permafrost degradation – a 20-years perspective'
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Geophysical measurements offer important baseline datasets as well as validation for modelling and remote sensing products for cryospheric sciences. Applications include the dynamics of ice-sheets, alpine glaciers and sea ice, changes in snow cover properties of seasonal and permanent snow, snow/ice-atmosphere-ocean interactions, permafrost degradation, geomorphic processes and changes in subsurface materials.

In this session we welcome contributions related to a wide spectrum of geophysical- and in-situ methods, including advances in diverse techniques such as radioglaciology, active and passive seismology, acoustic sounding, GPS/GNSS reflectometry or time delay techniques, cosmic ray neutron sensing, drone applications, geoelectrics and NMR. Contributions may concern field applications as well as new approaches in geophysical/in-situ survey techniques or theoretical advances in the field of data analysis, processing or inversion. Case studies from all parts of the cryosphere such as snow, alpine glaciers, ice sheets, glacial and periglacial environments and sea ice are highly welcome. The focus of the session is to compare experiences in the application, processing, analysis and interpretation of different geophysical and in-situ techniques in these highly complex environments.

This session is offered as a PICO: an engaging presentation format that has been successfully tested for this session during the last three years at EGU. All selected contributions will present their research orally, and then further present their research using interactive screens. This results in rich scientific feedback and is an effective tool for communicating science with high visibility.

Process understanding is key to assessing the sensitivity of glacier systems to changing climate. Comprehensive glacier monitoring provides the base for large-scale assessment of glacier change. Glaciers are monitored on different spatio-temporal scales, from extensive seasonal mass balance studies at selected glaciers to multi-decadal repeat inventories at the scale of entire mountain ranges. Internationally coordinated glacier monitoring aims at combining in-situ measurement with remotely sensed data, and local process understanding with global coverage. This session invites studies from a variety of disciplines, from tropical to polar glaciers, addressing both in-situ and remotely sensed monitoring of glaciers, as well as uncertainty assessments.
Keynotes:
Laura Thomson & David Burgess (Canada): The role and response of Canada's Arctic glaciers: Lessons learned from >50 years of mass balance observations
Bryn Hubbard (UK): 3D structure of Khumbu Glacier, Nepal, from borehole experiments.

A wide range of processes in the earth system directly affect geodetic observations. This session invites a wide array of contributions which showcase the use of geodesy for Earth science and climate applications, providing crucial insights into the state and change of the earth system and/or understanding its processes.

Data driven quantification of water mass fluxes through boundaries of Earth’s different regions and spheres provides important insights to other geoscience communities and informs model validation and improvement. Changes in regional sea level and ocean circulation are observed by altimetry and gravimetry. Natural and anthropogenic alterations of the terrestrial water cycle lead to changes in river runoff, precipitation, evapotranspiration, and water storage which may cause surface deformation sensed by GNSS stations and InSAR measurements as well as mass/gravity changes observed by satellite/ground gravimetry. Mass changes in the ice sheets and glaciers are detectable by both geometrical and gravimetric techniques. And other novel applications of geodetic techniques are emerging in many fields.

In addition, individual sensor recordings are often affected by high-frequency variability caused by, e.g., tides in the solid Earth, oceans, and atmosphere and their corresponding crustal deformations affecting station positions; non-tidal temperature and moisture variability in the troposphere modifying microwave signal dispersion; rapid changes in the terrestrially stored water caused by hydrometeorologic extreme events; as well as swift variations in relative sea-level that are driven by mass and energy exchange of the global oceans with other components of the Earth system, which all might lead to temporal aliasing in observational records. 

This session invites a wide array of contributions which showcase the use of geodesy for Earth science and climate applications. This session aims to cover innovative ways to use GRACE, GRACE-FO and other low Earth orbiters, GNSS techniques, InSAR, radar altimetry, and their combination with in-situ observations. We welcome approaches which tackle the problem of separating signals of different geophysical origin, by taking advantage of model output and/or advanced processing and estimation techniques. Since the use of geodetic techniques is not always straightforward, we encourage authors to think of creative ways to make their findings, data and software more readily accessible to other communities in hydrology, ocean, cryospheric, atmospheric and climate sciences. With author consent, highlights from the oral and poster session will be tweeted with a dedicated hashtag during the conference in order to increase the impact of the session.

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.

In the last 20 years, a major breakthrough in palaeo-environmental research has been the utilisation of 2D and 3D seismic reflection data and its integration with borehole petrophysics and core lithologies: the so-called “geological Hubble”. This step-change in seismic data quality and interpretive techniques has allowed imaging and analysis of the subsurface from the seafloor down to the Moho, and for palaeo-geographies and contemporary processes to be reconstructed across 1D (borehole) to 4D (repeat seismic) scales.

Though many Earth scientists know the basic principles of these subsurface datasets, they are often unaware of the full capability of seismic data paired with borehole data. We hope that this session will provide a window into the exciting and cross-disciplinary research currently being performed using geomorphological approaches, state-of-the-art seismic interpretation, and integrative methodologies.

Submissions are welcome from a range of geological settings, thus, exposing seismic interpreters and non-specialists to differing geological perspectives, the latest seismic workflows, and examples of effective seismic and borehole integration. Examples could include (but are not restricted to), glacigenic tunnel valley complexes, igneous intrusions, submarine landslides, channel and canyon systems, salt tectonics overburden expression, methane hydrates, and subsurface fluid flow, all under the theme of how seismic data are interpreted and how the results are applied (e.g. palaeo-environmental reconstruction, seafloor engineering, or carbon sequestration).

The submissions will highlight the rationale behind the interpretation of seismic geometries and will generate discussions around potential issues of equifinality (i.e. similar seismic geometries arising from different Earth processes). We thus invite submissions that aim to present new insights in seismic geomorphology and particularly welcome studies integrating borehole and geotechnical drilling information with shallow high-resolution seismic data and deeper traditional legacy oil industry data. Such studies are a crucial component in seismic inversion and refining or elucidating the accuracy of palaeo-geographies that are interpreted from just seismic data.

The session will be an excellent opportunity for subsurface geoscientists to showcase and discuss with contemporary geomorphologists and environmental scientists what can be achieved by utilising seismic and borehole data to unravel the Earth’s past.

Topographic data are fundamental to landscape characterization across the geosciences, for monitoring change and supporting process modelling. Over the last decade, the dominance of laser-based instruments for high resolution data collection has been challenged by advances in digital photogrammetry and computer vision, particularly in ‘structure from motion’ (SfM) algorithms, which offer a new paradigm to geoscientists.

High resolution topographic (HiRT) data are now obtained over spatial scales from millimetres to kilometres, and over durations of single events to lasting time series (e.g. from sub-second to decadal-duration time-lapse), allowing evaluation of dependencies between event magnitudes and frequencies. Such 4D-reconstruction capabilities enable new insight in diverse fields such as soil erosion, micro-topography reconstruction, volcanology, glaciology, landslide monitoring, and coastal and fluvial geomorphology. Furthermore, broad data integration from multiple sensors offers increasingly exciting opportunities.

This session will evaluate the advances in techniques to model topography and to study patterns of topographic change at multiple temporal and spatial scales. We invite contributions covering all aspects of HiRT reconstruction in the geosciences, and particularly those which transfer traditional expertise or demonstrate a significant advance enabled by novel datasets. We encourage contributions describing workflows that optimize data acquisition and post-processing to guarantee acceptable accuracies and to automate data application (e.g. geomorphic feature detection and tracking), and field-based experimental studies using novel multi-instrument and multi-scale methodologies. A major goal is to provide a cross-disciplinary exchange of experiences with modern technologies and data processing tools, to highlight their potentials, limitations and challenges in different environments.

Solicited speaker: Kuo-Jen Chang (National Taipei University of Technology) - UAS LiDAR data processing, quality assessment and geosciences prospects

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot aboard. Originating mostly from military applications, their use is rapidly expanding to commercial, recreational, agricultural, and scientific applications. Unlike manned aircraft, UAVs were initially used for missions too "dull, dirty, or dangerous" for humans. Nowadays however, many modern scientific experiments have begun to use UAVs as a tool to collect different types of data. Their flexibility and relatively simple usability now allow scientist to accomplish tasks that previously required expensive equipment like piloted aircrafts, gas, or hot air balloons. Even the industry has begun to adapt and offer extensive options in UAV characteristics and capabilities. At this session, we would like people to share their experience in using UAVs for scientific research. We are interested to hear about specific scientific tasks accomplished or attempted, types of UAVs used, and instruments deployed.

This session aims at bringing together multidisciplinary studies that address the current state of Arctic observing systems, including strategies to improve them in the future. We invite contributions covering atmosphere, ocean, cryosphere and terrestrial spheres, or combinations thereof, by use of remote sensing, in situ observation technologies, and modeling. Particular foci are placed on (i) the analysis of strengths, weaknesses, gaps in spatial/temporal coverage, and missing monitoring parameters in existing observation networks and databases, and (ii) studies describing the development and/or deployment of new sensors or observation platforms that extend the existing observing infrastructure with multidisciplinary measurements. This session will be supported by the EU-H2020 project INTAROS, and welcomes contributions from other pan-Arctic networks (e.g. INTERACT, GTN-P, NEON, ICOS, SIOS, IASOA, AOOS), multi-disciplinary campaigns (e.g. ABoVE, NGEE Arctic, Arctic Ocean 2018, RV Polarstern cruises) or databases.

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.