Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data
Consistent and continuous data on glacier surface velocity are important inputs to time series analyses, numerical ice dynamic modeling and glacier mass flux computations. Since 2014, repeat-pass synthetic aperture radar (SAR) data have been acquired by the Sentinel-1 satellite constellation as part...
Published in: | Earth System Science Data |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2021
|
Subjects: | |
Online Access: | https://doi.org/10.5194/essd-13-4653-2021 https://noa.gwlb.de/receive/cop_mods_00058360 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00058009/essd-13-4653-2021.pdf https://essd.copernicus.org/articles/13/4653/2021/essd-13-4653-2021.pdf |
id |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00058360 |
---|---|
record_format |
openpolar |
spelling |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00058360 2023-05-15T16:22:12+02:00 Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data Friedl, Peter Seehaus, Thorsten Braun, Matthias 2021-10 electronic https://doi.org/10.5194/essd-13-4653-2021 https://noa.gwlb.de/receive/cop_mods_00058360 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00058009/essd-13-4653-2021.pdf https://essd.copernicus.org/articles/13/4653/2021/essd-13-4653-2021.pdf eng eng Copernicus Publications Earth System Science Data -- http://www.earth-syst-sci-data.net/volumes_and_issues.html -- http://www.bibliothek.uni-regensburg.de/ezeit/?2475469 -- 1866-3516 https://doi.org/10.5194/essd-13-4653-2021 https://noa.gwlb.de/receive/cop_mods_00058360 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00058009/essd-13-4653-2021.pdf https://essd.copernicus.org/articles/13/4653/2021/essd-13-4653-2021.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2021 ftnonlinearchiv https://doi.org/10.5194/essd-13-4653-2021 2022-02-08T22:33:06Z Consistent and continuous data on glacier surface velocity are important inputs to time series analyses, numerical ice dynamic modeling and glacier mass flux computations. Since 2014, repeat-pass synthetic aperture radar (SAR) data have been acquired by the Sentinel-1 satellite constellation as part of the Copernicus program of the EU (European Union) and ESA (European Space Agency). It enables global, near-real-time-like and fully automatic processing of glacier surface velocity fields at up to 6 d temporal resolution, independent of weather conditions, season and daylight. We present a new global data set of glacier surface velocities that comprises continuously updated scene-pair velocity fields, as well as monthly and annually averaged velocity mosaics at 200 m spatial resolution. The velocity information is derived from archived and new Sentinel-1 SAR acquisitions by applying a well-established intensity offset tracking technique. The data set covers 12 major glacierized regions outside the polar ice sheets and is generated in an HPC (high-performance computing) environment at the University of Erlangen-Nuremberg. The velocity products are freely accessible via an interactive web portal that provides capabilities for download and simple online analyses: http://retreat.geographie.uni-erlangen.de (last access: 6 October 2021). In this paper, we give information on the data processing and how to access the data. For the example region of Svalbard, we demonstrate the potential of our products for velocity time series analyses at very high temporal resolution and assess the quality of our velocity products by comparing them to those generated from very high-resolution TerraSAR-X SAR and Landsat-8 optical (ITS_LIVE, GoLIVE) data. The subset of Sentinel-1 velocities for Svalbard analyzed in this paper is accessible via the GFZ Potsdam Data Services under the DOI https://doi.org/10.5880/fidgeo.2021.016 (Friedl et al., 2021). We find that Landsat-8 and Sentinel-1 annual velocity mosaics are in an overall good agreement, but speckle tracking on Sentinel-1 6 d repeat acquisitions derives more reliable velocity measurements over featureless and slow-moving areas than the optical data. Additionally, uncertainties of 12 d repeat Sentinel-1 mid-glacier scene-pair velocities have less than half (< 0.08 m d−1) of the uncertainties derived for 16 d repeat Landsat-8 data (0.17–0.18 m d−1). Article in Journal/Newspaper glacier Svalbard Niedersächsisches Online-Archiv NOA Svalbard The Sentinel ENVELOPE(73.317,73.317,-52.983,-52.983) Earth System Science Data 13 10 4653 4675 |
institution |
Open Polar |
collection |
Niedersächsisches Online-Archiv NOA |
op_collection_id |
ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
spellingShingle |
article Verlagsveröffentlichung Friedl, Peter Seehaus, Thorsten Braun, Matthias Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
topic_facet |
article Verlagsveröffentlichung |
description |
Consistent and continuous data on glacier surface velocity are important inputs to time series analyses, numerical ice dynamic modeling and glacier mass flux computations. Since 2014, repeat-pass synthetic aperture radar (SAR) data have been acquired by the Sentinel-1 satellite constellation as part of the Copernicus program of the EU (European Union) and ESA (European Space Agency). It enables global, near-real-time-like and fully automatic processing of glacier surface velocity fields at up to 6 d temporal resolution, independent of weather conditions, season and daylight. We present a new global data set of glacier surface velocities that comprises continuously updated scene-pair velocity fields, as well as monthly and annually averaged velocity mosaics at 200 m spatial resolution. The velocity information is derived from archived and new Sentinel-1 SAR acquisitions by applying a well-established intensity offset tracking technique. The data set covers 12 major glacierized regions outside the polar ice sheets and is generated in an HPC (high-performance computing) environment at the University of Erlangen-Nuremberg. The velocity products are freely accessible via an interactive web portal that provides capabilities for download and simple online analyses: http://retreat.geographie.uni-erlangen.de (last access: 6 October 2021). In this paper, we give information on the data processing and how to access the data. For the example region of Svalbard, we demonstrate the potential of our products for velocity time series analyses at very high temporal resolution and assess the quality of our velocity products by comparing them to those generated from very high-resolution TerraSAR-X SAR and Landsat-8 optical (ITS_LIVE, GoLIVE) data. The subset of Sentinel-1 velocities for Svalbard analyzed in this paper is accessible via the GFZ Potsdam Data Services under the DOI https://doi.org/10.5880/fidgeo.2021.016 (Friedl et al., 2021). We find that Landsat-8 and Sentinel-1 annual velocity mosaics are in an overall good agreement, but speckle tracking on Sentinel-1 6 d repeat acquisitions derives more reliable velocity measurements over featureless and slow-moving areas than the optical data. Additionally, uncertainties of 12 d repeat Sentinel-1 mid-glacier scene-pair velocities have less than half (< 0.08 m d−1) of the uncertainties derived for 16 d repeat Landsat-8 data (0.17–0.18 m d−1). |
format |
Article in Journal/Newspaper |
author |
Friedl, Peter Seehaus, Thorsten Braun, Matthias |
author_facet |
Friedl, Peter Seehaus, Thorsten Braun, Matthias |
author_sort |
Friedl, Peter |
title |
Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
title_short |
Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
title_full |
Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
title_fullStr |
Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
title_full_unstemmed |
Global time series and temporal mosaics of glacier surface velocities derived from Sentinel-1 data |
title_sort |
global time series and temporal mosaics of glacier surface velocities derived from sentinel-1 data |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/essd-13-4653-2021 https://noa.gwlb.de/receive/cop_mods_00058360 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00058009/essd-13-4653-2021.pdf https://essd.copernicus.org/articles/13/4653/2021/essd-13-4653-2021.pdf |
long_lat |
ENVELOPE(73.317,73.317,-52.983,-52.983) |
geographic |
Svalbard The Sentinel |
geographic_facet |
Svalbard The Sentinel |
genre |
glacier Svalbard |
genre_facet |
glacier Svalbard |
op_relation |
Earth System Science Data -- http://www.earth-syst-sci-data.net/volumes_and_issues.html -- http://www.bibliothek.uni-regensburg.de/ezeit/?2475469 -- 1866-3516 https://doi.org/10.5194/essd-13-4653-2021 https://noa.gwlb.de/receive/cop_mods_00058360 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00058009/essd-13-4653-2021.pdf https://essd.copernicus.org/articles/13/4653/2021/essd-13-4653-2021.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/essd-13-4653-2021 |
container_title |
Earth System Science Data |
container_volume |
13 |
container_issue |
10 |
container_start_page |
4653 |
op_container_end_page |
4675 |
_version_ |
1766010177865121792 |