{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:54:13Z","timestamp":1760147653598,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41906199","E0C01kA340","EOPD40012S"],"award-info":[{"award-number":["41906199","E0C01kA340","EOPD40012S"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Foundation of Key Laboratory of Space Ocean Remote Sensing and Application, MNR","award":["41906199","E0C01kA340","EOPD40012S"],"award-info":[{"award-number":["41906199","E0C01kA340","EOPD40012S"]}]},{"name":"Youth Innovation Project of National Space Science Center of Chinese Academy of Sciences","award":["41906199","E0C01kA340","EOPD40012S"],"award-info":[{"award-number":["41906199","E0C01kA340","EOPD40012S"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Sea ice thickness (SIT) is an important parameter in the study of climate change. During the past 20 years, satellite altimetry has been widely used to observe sea ice thickness. The Chinese Haiyang-2B (HY-2B) radar altimeter, launched in October 2018, can provide data up to 80.6\u00b0 latitude and can be used as a supplementary means to observe polar sea ice. Reliable HY-2B SIT products will contribute to the sea ice community. In this study, we aimed to assess the Arctic sea ice thickness retrieval ability of the HY-2B radar altimetry data. We processed the HY-2B radar altimetry data from January 2019 to April 2022 and used the processed data to retrieve the Arctic SIT. The Alfred Wegener Institute (AWI) CryoSat-2 (CS-2) SIT products were used to calibrate the HY-2B SIT estimates with a linear regression method. The Goddard Space Flight Center (GSFC) CS-2, Jet Propulsion Laboratory (JPL), and GSFC ICESat-2 (IS-2) SIT products were used to validate the HY-2B calibrated SIT estimates. The HY-2B calibrated SIT estimates have good, consistent spatial distributions with the CS-2 and IS-2 SIT products. The comparison with the IS-2 and IS-2 SIT products shows the root-mean-square error (RMSE) and bias for the HY-2B SIT estimates are significantly reduced after calibration. The HY-2B SIT estimates were also validated using the ice thickness data from Operation IceBridge (OIB) and the ice draft data from the Beaufort Gyre Exploration Project (BGEP). Finally, the monthly variations of the HY-2B SIT estimates were analyzed. Results show that the HY-2B calibrated SIT estimates are reliable, especially when the SIT values are lower than 3 m. The HY-2B altimetry data is a possible source for sea ice thickness data at lower latitudes and will help us better understand the sea ice response to climate change.<\/jats:p>","DOI":"10.3390\/rs15051180","type":"journal-article","created":{"date-parts":[[2023,2,22]],"date-time":"2023-02-22T01:39:47Z","timestamp":1677029987000},"page":"1180","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Estimation of Arctic Sea Ice Thickness from Chinese HY-2B Radar Altimetry Data"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4688-6260","authenticated-orcid":false,"given":"Maofei","family":"Jiang","sequence":"first","affiliation":[{"name":"The CAS Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences (CAS), Beijing 100190, China"}]},{"given":"Wenqing","family":"Zhong","sequence":"additional","affiliation":[{"name":"The CAS Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Ke","family":"Xu","sequence":"additional","affiliation":[{"name":"The CAS Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences (CAS), Beijing 100190, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9579-1217","authenticated-orcid":false,"given":"Yongjun","family":"Jia","sequence":"additional","affiliation":[{"name":"Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, Beijing 100081, China"},{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1038\/nature06590","article-title":"Ocean circulation in a warming climate","volume":"451","author":"Toggweiler","year":"2008","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1038\/17018","article-title":"Oceanography: All change in the Arctic","volume":"397","author":"Dickson","year":"1999","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1029\/2006GL028024","article-title":"Future abrupt reductions in the summer Arctic sea ice","volume":"33","author":"Holland","year":"2006","journal-title":"Geophys. 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