{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T10:29:16Z","timestamp":1763202556057,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T00:00:00Z","timestamp":1639440000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"publisher","award":["727890"],"award-info":[{"award-number":["727890"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Studies of global sea level often exclude Tide Gauges (TGs) in glaciated regions due to vertical land movement. Recent studies show that geodetic GNSS stations can be used to estimate sea level by taking advantage of the reflections from the ocean surface using GNSS Interferometric Reflectometry (GNSS-IR). This method has the immediate benefit that one can directly correct for bedrock movements as measured by the GNSS station. Here we test whether GNSS-IR can be used for measurements of inter annual sea level variations in Thule, Greenland, which is affected by sea ice and icebergs during much of the year. We do this by comparing annual average sea level variations using the two methods from 2008\u20132019. Comparing the individual sea level measurements over short timescales we find a root mean square deviation (RMSD) of 13 cm, which is similar to other studies using spectral methods. The RMSD for the annual average sea level variations between TG and GNSS-IR is large (18 mm) compared to the estimated uncertainties concerning the measurements. We expect that this is in part due to the TG not being datum controlled. We find sea level trends from GNSS-IR and TG of \u22124 and \u22127 mm\/year, respectively. The negative trend can be partly explained by a gravimetric decrease in sea level as a result of ice mass changes. We model the gravimetric sea level from 2008\u20132017 and find a trend of \u22123 mm\/year.<\/jats:p>","DOI":"10.3390\/rs13245077","type":"journal-article","created":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T22:06:10Z","timestamp":1639519570000},"page":"5077","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["GNSS-IR Measurements of Inter Annual Sea Level Variations in Thule, Greenland from 2008\u20132019"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0649-4844","authenticated-orcid":false,"given":"Trine S.","family":"Dahl-Jensen","sequence":"first","affiliation":[{"name":"Danish National Space Centre, Technical University of Denmark, 2800 Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6685-3415","authenticated-orcid":false,"given":"Ole B.","family":"Andersen","sequence":"additional","affiliation":[{"name":"Danish National Space Centre, Technical University of Denmark, 2800 Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4123-4973","authenticated-orcid":false,"given":"Simon D. P.","family":"Williams","sequence":"additional","affiliation":[{"name":"National Oceanography Center, Liverpool L3 5DA, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7788-9328","authenticated-orcid":false,"given":"Veit","family":"Helm","sequence":"additional","affiliation":[{"name":"Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2689-8563","authenticated-orcid":false,"given":"Shfaqat A.","family":"Khan","sequence":"additional","affiliation":[{"name":"Danish National Space Centre, Technical University of Denmark, 2800 Lyngby, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,14]]},"reference":[{"key":"ref_1","first-page":"1067","article-title":"New estimates of secular sea level rise from tide gauge data and GIA modelling","volume":"191","author":"Spada","year":"2012","journal-title":"Geophys. J. 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