{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T09:16:49Z","timestamp":1773479809278,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,27]],"date-time":"2021-10-27T00:00:00Z","timestamp":1635292800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Singapore Ministry of Education Academic Research Fund Tier 3","award":["MOE 2019-T3-1-004"],"award-info":[{"award-number":["MOE 2019-T3-1-004"]}]},{"name":"National Research Foundation Singapore under its NRF Investigatorship scheme","award":["NRF-NRFI05-2019-0009"],"award-info":[{"award-number":["NRF-NRFI05-2019-0009"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Rising sea levels pose one of the greatest threats to coastal zones. However, sea-level changes near the coast, particularly absolute sea-level changes, have been less well monitored than those in the open ocean. In this study, we aim to investigate the potential of Global Navigation Satellite Systems Interferometric Reflectometry (GNSS-IR) to measure coastal absolute sea-level changes and tie on-land (coastal GNSS) and offshore (satellite altimetry) observations into the same framework. We choose three coastal GNSS stations, one each in regions of subsidence, uplift and stable vertical land motions, to derive both relative sea levels and sea surface heights (SSH) above the satellite altimetry reference ellipsoid from 2008 to 2020. Our results show that the accuracy of daily mean sea levels from GNSS-IR is &lt;1.5 cm compared with co-located tide-gauge records, and amplitudes of annual cycle and linear trends estimated from GNSS-IR measurements and tide-gauge data agree within uncertainty. We also find that the de-seasoned and de-trended SSH time series from GNSS-IR and collocated satellite altimetry are highly correlated and the estimated annual amplitudes and linear trends statistically agree well, indicating that GNSS-IR has the potential to monitor coastal absolute sea-level changes and provide valuable information for coastal sea-level and climate studies.<\/jats:p>","DOI":"10.3390\/rs13214319","type":"journal-article","created":{"date-parts":[[2021,10,27]],"date-time":"2021-10-27T23:26:38Z","timestamp":1635377198000},"page":"4319","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Measuring Coastal Absolute Sea-Level Changes Using GNSS Interferometric Reflectometry"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7152-7534","authenticated-orcid":false,"given":"Dongju","family":"Peng","sequence":"first","affiliation":[{"name":"Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3736-5025","authenticated-orcid":false,"given":"Lujia","family":"Feng","sequence":"additional","affiliation":[{"name":"Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4666-8885","authenticated-orcid":false,"given":"Kristine M.","family":"Larson","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering Sciences, University of Colorado Boulder, Boulder, CO 80303, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0231-5818","authenticated-orcid":false,"given":"Emma M.","family":"Hill","sequence":"additional","affiliation":[{"name":"Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore"},{"name":"Asian School of the Environment, Nanyang Technological University, Singapore 639798, Singapore"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"eaat1180","DOI":"10.1126\/sciadv.aat1180","article-title":"A modest 0.5-m rise in sea level will double the tsunami hazard in Macau","volume":"4","author":"Li","year":"2018","journal-title":"Sci. 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