{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T07:46:50Z","timestamp":1761896810169,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2018,6,12]],"date-time":"2018-06-12T00:00:00Z","timestamp":1528761600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["4000104815\/11\/I-NB"],"award-info":[{"award-number":["4000104815\/11\/I-NB"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ice velocity is one of the products associated with the Ice Sheets Essential Climate Variable. This paper describes the intercomparison and validation of ice-velocity measurements carried out by several international research groups within the European Space Agency Greenland Ice Sheet Climate Change Initiative project, based on space-borne Synthetic Aperture Radar (SAR) data. The goal of this activity was to survey the best SAR-based measurement and error characterization approaches currently in practice. To this end, four experiments were carried out, related to different processing techniques and scenarios, namely differential SAR interferometry, multi aperture SAR interferometry and offset-tracking of incoherent as well as of partially-coherent data. For each task, participants were provided with common datasets covering areas located on the Greenland ice-sheet margin and asked to provide mean velocity maps, quality characterization and a description of processing algorithms and parameters. The results were then intercompared and validated against GPS data, revealing in several cases significant differences in terms of coverage and accuracy. The algorithmic steps and parameters influencing the coverage, accuracy and spatial resolution of the measurements are discussed in detail for each technique, as well as the consistency between quality parameters and validation results. This allows several recommendations to be formulated, in particular concerning procedures which can reduce the impact of analyst decisions, and which are often found to be the cause of sub-optimal algorithm performance.<\/jats:p>","DOI":"10.3390\/rs10060929","type":"journal-article","created":{"date-parts":[[2018,6,12]],"date-time":"2018-06-12T10:58:32Z","timestamp":1528801112000},"page":"929","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Intercomparison and Validation of SAR-Based Ice Velocity Measurement Techniques within the Greenland Ice Sheet CCI Project"],"prefix":"10.3390","volume":"10","author":[{"given":"John Peter","family":"Merryman Boncori","sequence":"first","affiliation":[{"name":"DTU Space Institute, Technical University of Denmark (DTU), DK-2800 Kongens Lyngby, Denmark"}]},{"given":"Morten","family":"Langer Andersen","sequence":"additional","affiliation":[{"name":"Geological Survey of Denmark and Greenland (GEUS), Department of Glaciology and Climate, DK-1350 Copenhagen, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3873-1074","authenticated-orcid":false,"given":"J\u00f8rgen","family":"Dall","sequence":"additional","affiliation":[{"name":"DTU Space Institute, Technical University of Denmark (DTU), DK-2800 Kongens Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7822-4758","authenticated-orcid":false,"given":"Anders","family":"Kusk","sequence":"additional","affiliation":[{"name":"DTU Space Institute, Technical University of Denmark (DTU), DK-2800 Kongens Lyngby, Denmark"}]},{"given":"Martijn","family":"Kamstra","sequence":"additional","affiliation":[{"name":"Science &amp; Technology AS (S&amp;T), N-0160 Oslo, Norway"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8216-0141","authenticated-orcid":false,"given":"Signe","family":"Bech Andersen","sequence":"additional","affiliation":[{"name":"Geological Survey of Denmark and Greenland (GEUS), Department of Glaciology and Climate, DK-1350 Copenhagen, Denmark"}]},{"given":"Noa","family":"Bechor","sequence":"additional","affiliation":[{"name":"Earth Resources Laboratory, Massachussets Institute of Technology (MIT), Boston, MA 02139, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2649-2982","authenticated-orcid":false,"given":"Suzanne","family":"Bevan","sequence":"additional","affiliation":[{"name":"Department of Geography, College of Science, Swansea University, Swansea SA28PP, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8632-9979","authenticated-orcid":false,"given":"Christian","family":"Bignami","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia (INGV), Centro Nazionale Terremoti, 00143 Rome, Italy"}]},{"given":"Noel","family":"Gourmelen","sequence":"additional","affiliation":[{"name":"Institute of Geography, University of Edinburgh, Edinburgh EH89XP, UK"}]},{"given":"Ian","family":"Joughin","sequence":"additional","affiliation":[{"name":"Applied Physics Laboratory, University of Washington, Seattle, WA 98105, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2335-8438","authenticated-orcid":false,"given":"Hyung-Sup","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Geoinformatics, University of Seoul, 02504 Seoul, Korea"}]},{"given":"Adrian","family":"Luckman","sequence":"additional","affiliation":[{"name":"Department of Geography, College of Science, Swansea University, Swansea SA28PP, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9155-5455","authenticated-orcid":false,"given":"Jeremie","family":"Mouginot","sequence":"additional","affiliation":[{"name":"Department of Earth System Science, University of California Irvine, Irvine, CA 92967, USA"},{"name":"CNRS, IRD, Grenoble INP, IGE, Universit\u00e9 Grenoble Alpes, 38000 Grenoble, France"}]},{"given":"Julia","family":"Neelmeijer","sequence":"additional","affiliation":[{"name":"German Research Centre for Geosciences (GFZ Potsdam), 14473 Potsdam, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3366-0481","authenticated-orcid":false,"given":"Eric","family":"Rignot","sequence":"additional","affiliation":[{"name":"Department of Earth System Science, University of California Irvine, Irvine, CA 92967, USA"}]},{"given":"Kilian","family":"Scharrer","sequence":"additional","affiliation":[{"name":"Environmental Earth Observation IT GmbH (ENVEO), A-6020 Innsbruck, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1298-8469","authenticated-orcid":false,"given":"Thomas","family":"Nagler","sequence":"additional","affiliation":[{"name":"Environmental Earth Observation IT GmbH (ENVEO), A-6020 Innsbruck, Austria"}]},{"given":"Bernd","family":"Scheuchl","sequence":"additional","affiliation":[{"name":"Department of Earth System Science, University of California Irvine, Irvine, CA 92967, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9054-951X","authenticated-orcid":false,"given":"Tazio","family":"Strozzi","sequence":"additional","affiliation":[{"name":"Gamma Remote Sensing AG, CH-3073 G\u00fcmligen, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/0034-4257(92)90101-O","article-title":"Application of image cross-correlation to the measurement of glacier velocity using satellite image data","volume":"42","author":"Scambos","year":"1992","journal-title":"Remote Sens. 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