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.

This is a joined session - we merged with the former session SM5.5 'Active and passive seismic methods for imaging and monitoring the cryosphere'.


++++++++++++++++++++++++++++ Invited Speaker ++++++++++++++++++++++++++++++++++++

Dustin Schroeder: Observing Evolving Subglacial Conditions with Muti-Temporal Radar Sounding

Public information:
Session topics:
A) Glaciers, Englacial and Subglacial: Schroeder (invited), Rix & Mulvaney et al., Yushkova et al., Jansen et al., Delf et al., Church et al., Pettinelli et al., Kufner et al., Mordret et al., Brisbourne et al., Jones et al., Stevens et al.
B) Sea Ice & Ocean Floors: Jakovlev et al., Schlindwein et al.
C) Ice Rheology: Hellmann et al., Booth et al., Ershadi et al., Martin et al.
D) Snow & Firn: Case et al., Pearce et al., Priestley, Capelli et al., Henkel et al.
E) Permafrost: Maierhofer et al., Limbrock et al., Boaga et al., Lyu et al., Valois et al., Majdanski et al.

Besides our EGU2020: Sharing Geoscience Online text-based chat on Mon, 04 May, 08:30–10:15, we are planning an additional video conference (outside the EGU programme) at the same day starting at 18:00/06:00p.m. In this video conference, our invited speaker Dustin Schroeder will give his talk on ‘Observing Evolving Subglacial Conditions with Mutitemporal Radar Sounding’. We will then open a broader discussion on all different topics and methods of our session.
Time: Mon, 04 May, start: 18:00/06:00p.m. Vienna time (CEST) (= 12:00 New York time)
Place/Link: https://rutgers.webex.com/rutgers/k2/j.php?MTID=tc085b8a9bc24b1c04784c81584672fc4
Session password: YvBGu8jV773 (Global call-in numbers: https://rutgers.webex.com/rutgers/globalcallin.php?MTID=t7ddb8d0ab92b0bd317c7e36862494393 Access code: 192 664 533)

@all authors of this session: It would be great if you can help us a bit in our session planning. Therefore, we would like to ask you to complete the following Doodle survey asap: https://doodle.com/poll/sese8bcs57dcfye5
In this survey we would like to know, if you will be able to
a) upload a display until Thu, 30 April
b) participate during our official EGU2020: Sharing Geoscience Online text-based chat on Mon, 04 May, 08:30–10:15 am
c) participate during our additional video conference on Mon, 04 May, 18:00/6p.m. (please pay attention, time was updated!)
Thank you very much for your help.

Studies of ice extent, volume and dynamics during former glaciations are important for understanding past climates and evolution of the Earth’s surface, and also provide analogies for present-day ice sheets and their subglacial environments. This includes observations of glacial erosion, glacial transport and deposition of sediments, formation of fjords and their relation to ice streams, evidence for migration of ice divides, former locations of subglacial lakes, relations between high geothermal heat flow, basal ice melt and rapid ice flow, and other aspects of paleo glacier extent and behaviour. This session will bring together the interdisciplinary scientific community working on former ice covers from the perspectives of glacial geomorphology, quaternary geology, and numerical modeling. It will provide a forum in which field-based reconstructions and model-based simulations can be compared and contrasted. We particularly welcome contributions that shed light on ancient and more recent glaciations on Earth and their interaction with other components of the Earth System.

The explosion of data and computing power that is now available to glaciologists presents significant opportunities for advancing our understanding of glacial environments. However, significant barriers exist to achieving this, with the scales and rates at which data are being generated rendering many traditional approaches to analysis impractical.
Researchers across nearly all fields of glaciology are therefore increasingly requiring the development of automated and/or machine learning based approaches to effectively monitor and investigate these environments, in addition to new ways of visualising results. This session will therefore bring together glaciologists who use big data, machine learning and/or artificial intelligence to help share knowledge of different approaches that are currently being taken by the community and where possible demonstrate their potential transferability in this emergent field. Contributions are invited from those involved in developing and/or applying methods that seek to address these data generation, analytical and visualisation challenges with the aim of gaining greater understanding of past, present and future glacier and ice sheet change.

Public information:
During the chat session we will provide the opportunity for our presenters to briefly introduce their work and answer questions. If there is time, we will also facilitate a discussion for authors and attendees to discuss the following topics:

1. What are the challenges experienced by those applying big data/machine learning/AI techniques, and how can those involved in other areas of glaciology help?

2. What are the challenges of experienced by those using big data/machine learning/AI data products, and how can those creating them make them more accessible?

Other topics for discussion are very much encouraged both from those working with big/machine learning/AI data and those who may be interested in the potential of such approaches in glaciology.

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 and would like to highlight the session on twitter.

Public information:
- Each presentation will have a dedicated discussion section underneath, similar to the comments and reply format for The Cryosphere journal. The presentation materials and discussion will still be available once the session ends.
- There will also be one text-based “live chat” channel per session. The link becomes active 15 minutes prior to scheduled session start and disappears 30 minutes after the scheduled end of the session.

------ What to upload ------

- Upload slides/poster/other of your work. There is no distinction between oral and poster assigned slots, so please make your presentation as original and engaging as possible!
- Considering the limitations with presenting work in a typical “oral” format, a poster or just a few slides might work better
- Please add a very brief summary (1-2 sentences) of your presentation as the first comment in the discussion section underneath. This should be short enough to fit in a tweet. We’ll be tweeting these out to advertise the session so if you’d rather we didn’t, please let us know!
- Optional: Feel free to record a short summary (5 minutes maximum; video or audio) of what you’ll be presenting. There is a 50 MB upload limit.

------ Presenter participation ------

We realise it will be hard for a number of presenters to attend the session in real time due to time zone constraints. Therefore, we ask all presenters to:
- Respond to the discussion on your presentation after the session’s scheduled time is over
- Don’t forget to add your brief summary (1-2 sentences) of your presentation as the first comment in the discussion section underneath

------ Live chat rules ------

- Please only use the live chat window for comments and questions that you think would be of wide interest to the session, rather than comments for individual presentations
- At least one convener will be available at all times during the live chat
- We will use the live chat window to highlight your presentation summaries
- More information on the live chat can be found at https://egu2020.eu/sharing_geoscience_online/how_to_use_the_chats.html

------ FAQs ------

Hopefully any questions we haven’t answered will be at https://egu2020.eu/sharing_geoscience_online/sharing_geoscience_online.html#faqs

Thanks again for being open to this new format, and let us know if you have any questions or difficulties regarding the session. Looking forward to some great conversations next week!

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.

This year we have combined session CR2.7 with CR1.6 "Glaciers and ice caps under climate change":
Mountain glaciers and ice caps are major contributors to sea-level rise and have large impacts on water balance of local basins. This is a general session on glaciers and ice caps where the relationship to climate forms a particular focus. The IPCC AR5 of Working Group 1 covers Earths Glaciers and Ice Caps outside the ice sheets under the heading of Glaciers and shows that, despite much progress recently provided by the community, we are still left with substantial unknowns. We need to acquire more data, both from new fieldwork and release of unpublished data from prior years on mass changes of glaciers and ice caps from all regions of the world. We need to improve the understanding of the processes behind the changes, and we need to improve the application of models of different complexity. We welcome presentations on all aspects of mass changes; current, past and future changes based on field observations, remote sensing and modeling. Studies of physical processes controlling accumulation and ablation including calving and submarine melting, are especially welcome.

Solicited speakers:
Joshua R. Leigh: 'Identifying and mapping very small mountain glaciers on coarse to high-resolution imagery'
Martin Hoelzle: 'Glacier monitoring, capacity building and related cryospheric research in Central Asia'

Public information:
The nominal schedule can be found in the 'Session materials' file.

Space-based measurements of the Earth System, including its atmosphere, oceans, land surface, cryosphere, biosphere, and interior, require extensive prelaunch and post launch calibration and validation activities to ensure scientific accuracy and fitness for purpose throughout the 
lifetime of satellite missions. This requirement stems from the need to demonstrate unambiguously that the space-based measurements, typically based on engineering measurements by the detectors (e.g. photons), are sensitive to and match up with the geophysical and/or biogeochemical quantity of interest at a broad range of measurement locations on Earth. Most geophysical parameters vary in time and space, and the retrieval algorithms used must be accurate under the full range of conditions. Calibration and validation need to be carried out over the lifetime of missions in order to assure that any long-term variation in observation can be definitely be tied to the evolution of the Earth system. Such activities are also critical in ensuring that measurements can be inter-compared and used seamlessly to create long-term multi-instrument//multi-platform data sets, , which enable large-scale international science investigations into topics with high societal or environmental importance such as determining the ice mass balance of Greenland, monitoring the evolution of sea ice and snow cover in the Arctic and improving our knowledge of the terrestrial carbon cycle through multi-sensor forest biomass mapping. . This session seeks presentations on the use of surface-based, airborne, and/or space-based observations to prepare and calibrate/validate space-based satellite missions measuring our Earth system. A particular but not exclusive focus will be on activities carried out jointly by NASA and ESA as part of their Joint Program Planning Group Subgroup on calibration and validation and field activities.

Satellite altimetry provides the possibility to observe key parts of the hydrosphere, namely the ocean, ice, and continental surface water from space. Since the launch of Topex/Poseidon in 1992 the applications of altimetry have expanded from the open oceans to coastal zones, inland water, land and sea ice. Today, seven missions are in orbit, providing dense and near-global observations of surface elevation and several other parameters. Satellite altimetry has become an integral part of the global observation of the Earth‘s system and changes therein.

In recent years, new satellite altimetry missions have been launched carrying new instruments and operating in new orbits; the CryoSat-2/Sentinel-3 missions equipped with a Delay/Doppler altimeter, the Saral AltiKa mission carrying the first Ka band altimeter, and the recently launched photon counting laser altimeter on-board NASAs ICESat-2.

Fully exploiting this unprecedented availability of observables will enable new applications and results but also require novel and adapted methods of data analysis.
Across the different applications for satellite altimetry, the data analysis and underlying methods are similar and a knowledge exchange between the disciplines will be fruitful.
In this multidisciplinary altimetry session, we therefore invite contributions which discuss new methodology and applications for satellite altimetry in the fields of geodesy, hydrology, cryosphere, oceanography, and climatology.
Topics of such studies could for example be (but not limited to): creation of robust and consistent time series across sensors, validation experiments, combination of radar and laser altimetry e. g. for remote sensing of snow, classification of waveforms, application of data in a geodetic orbit, retracking, or combination with other remote sensing data sets.

Ice cores are a key archive to study past climate variability. Various physico-chemical proxies provide key insights into past temperature, atmospheric composition, volcanic activity, and atmospheric circulation. Despite the large body of empirical information available, we still lack a detailed, process-based understanding of the creation of the archived climatic signal. This session aims, in light of the new "Beyond EPICA Oldest Ice" (BE-OI) ice-core project, at an in-depth discussion on the extent to which climatic signals are archived in the proxy signals, how the archival processes – from the atmosphere to the surface to post-depositional changes in the firn and ice and even further smoothing/diffusion in the lower most part of the ice column – themselves affect the recorded signal, and how to optimally recover the original signals from existing ice-core records. We welcome contributions that shed light on this chain of processes, including interpretation of various proxies from new, or existing, ice core records from Antarctica, Greenland or high mountainous areas; analyses of climate model, reanalysis and back trajectory data; novel application of statistical and spectral methods to proxy data; or new measurement techniques. Finally, we encourage discussion about the impact the individual processes have on the relationship between proxy and past climate variability across various temporal and spatial scales.

Public information:
Brief live chat info (10:45 am - 12:30 pm CET Tuesday 5th May)
- 10:45 am - 11:45 am: discussion of the uploaded presentations (similar to PICO sessions)
where presenters can explain their slides/answer questions
- 11:45 am - 12:30 pm: group discussion on 2 to 3 broader topics based on the themes of
the presentations
- We encourage short powerpoint presentations (1-3 slides)
- Choose a single focus and main conclusion from your presented research

This session is a result of a merge between GI1.3 and GM2.3:

Recent advances in image collection and topographic measurements are providing unprecedented insight into landscape and process characterization across the geosciences. In parallel, the increasing availability of digitised historical images, going back to the late 1800s, together with advances in digital photogrammetry software, have provided new opportunities for assessing and reconstructing long-term surface evolution from local to landscape scale. Such data can extend high-resolution time series into the pre-satellite era and offer exciting potential for distinguishing anthropogenic from natural causes of environmental change. For both historic and contemporary scenarios, augmenting classic techniques with digital imagery and ‘structure from motion’ (SfM) processing has democratized data access and offers a new measurement paradigm to geoscientists.

Such data are now available over spatial scales from millimetres to kilometres, and over durations of single events to lasting time series (e.g. from sub-second to century-duration time-lapse), allowing evaluation of event magnitude and frequency interrelationships. Despite a large volume of historical images available for reprocessing with modern methods, their full potential has not yet been widely exploited and uncertainties remain on the optimal types of information that can be extracted. Substantial opportunities are likely to be exposed by exploring such data resources with machine and deep learning approaches.

The session welcomes submissions from a broad range of geoscience disciplines such as geomorphology, cryosphere, volcanology, hydrology, bio-geosciences, and geology. Our goal is to create a diverse and interdisciplinary session to explore the potential of 2D and 3D image and topographic datasets for reconstructing and interpreting environments and processes, past and present. We aim to exchange experiences of modern photogrammetric and topographic measurement and modelling technologies, along with their associated data processing tools, to highlight their potentials, limitations, and challenges in different environments.

Public information:
We will have a video meeting on Friday evening starting from 6 pm CEST (UTC+2), in addition to the chat session on Friday morning, as scheduled. Authors will give talks in this video meeting, and there will be room for discussions, with the following agenda:

18:00 - 18:05 - Meeting setting and introduction to the session
18:05 - 18:17 - Amaury Dehecq, "Multidecadal elevation changes from spy satellite images: application to glaciers and landslides".
18:17 - 18:29 - Robert McNabb, "An open-source toolset for automated processing of historic spy photos: sPyMicMac".
18:29 - 18:41 - Penelope How, "PyTrx: a Python-based monoscopic terrestrial photogrammetry toolset for glaciology".
18.41 - 18:53 - Sebastian Flöry, "Development of a 3D Viewer for georeferencing and monoplotting of historical terrestrial images".
18.53 - 19:05 - Luca Carturan, "Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front".
19:05 - 19:17 - Martino Terrone, "Coupling historical maps and Lidar data to recognize man-made landforms in urban areas".
19:17 - 19:25 - a little break
19:25 - 19:37 - William D. Harcourt. "Observing the cryosphere with millimetre wave radar: The case study of Rhône Glacier".
19.37 - 19:49 - Denis Feurer, "Time-SIFT: a frugal method for leveraging multi-temporal photogrammetric data without ancillary data"
19.49 - 20:01 - Helge Smebye, "Combined aerial and ground-based Structure-from-Motion modelling for a vertical rock wall face to estimate volume of failure"
20:01 - 20:13 - Sara Cucchiaro, "Terrestrial-Aerial-SfM and TLS data fusion for agricultural terrace surveys in complex topographic and land cover conditions".
20:13 - 20:25 - Andreas Mayr, "Close-range sensing and object based analysis of shallow landslides and erosion in grasslands".
20:25 - 20:37 - Kieran Wood, "UAS radiation hot-spot detection and refinement."
20:37 - break and discussion with an open end.

Join the video meeting using the following link:
https://kuei.zoom.us/j/99949141405

For an optimal audio and video experience, we suggest that you join the meeting using the Zoom application. When following the meeting link, you will be asked to install it. Alternatively, you may join the meeting using the Chrome browser.