{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T09:23:49Z","timestamp":1771233829466,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2017,1,17]],"date-time":"2017-01-17T00:00:00Z","timestamp":1484611200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Qinghai-Tibetan plateau (QTP), also known as the Third Pole and the World Water Tower, is the largest and highest plateau with distinct and competing surface and subsurface processes. It is covered by a large layer of discontinuous and sporadic alpine permafrost which has degraded 10% during the past few decades. The average active layer thickness (ALT) increase rate is approximately 7.5 cm\u00b7yr\u22121 from 1995 to 2007, based on soil temperature measurements from 10 borehole sites along Qinghai-Tibetan Highway, and approximately 6.3 cm\u00b7yr\u22121, 2006\u20132010, using soil temperature profiles for 27 monitoring sites along Qinghai-Tibetan railway. In this study, we estimated the ALT and its AL thickening rate in the northern QTP near the railway using ALOS PALSAR L-band small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) data observed land subsidence and the corresponding ALT modeling. The InSAR estimated ALT and AL thickening rate were validated with ground-based observations from the borehole site WD4 within our study region, indicating excellent agreement. We concluded that we have generated high spatial resolution (30 m) and spatially-varying ALT and AL thickening rates, 2007\u20132009, over approximately an area of 150 km2 of permafrost-covered region in the northern QTP.<\/jats:p>","DOI":"10.3390\/rs9010084","type":"journal-article","created":{"date-parts":[[2017,1,18]],"date-time":"2017-01-18T10:00:47Z","timestamp":1484733647000},"page":"84","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Characterization of Active Layer Thickening Rate over the Northern Qinghai-Tibetan Plateau Permafrost Region Using ALOS Interferometric Synthetic Aperture Radar Data, 2007\u20132009"],"prefix":"10.3390","volume":"9","author":[{"given":"Yuanyuan","family":"Jia","sequence":"first","affiliation":[{"name":"Division of Geodetic Science, School of Earth Science, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9097-2465","authenticated-orcid":false,"given":"Jin-Woo","family":"Kim","sequence":"additional","affiliation":[{"name":"Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX 75275, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9378-4067","authenticated-orcid":false,"given":"C.","family":"Shum","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Science, Ohio State University, Columbus, OH 43210, USA"},{"name":"State Key Laboratory of Geodesy and Earth\u2019s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9181-1818","authenticated-orcid":false,"given":"Zhong","family":"Lu","sequence":"additional","affiliation":[{"name":"Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX 75275, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoli","family":"Ding","sequence":"additional","affiliation":[{"name":"Department of Land Surveying and Geo-Informatics, Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8152-2470","authenticated-orcid":false,"given":"Lei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Land Surveying and Geo-Informatics, Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kamil","family":"Erkan","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Marmara University, 34722 Istanbul, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3449-995X","authenticated-orcid":false,"given":"Chung-Yen","family":"Kuo","sequence":"additional","affiliation":[{"name":"Department of Geomatics, National Cheng Kung University, 70101 Tainan, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kun","family":"Shang","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Science, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3581-076X","authenticated-orcid":false,"given":"Kuo-Hsin","family":"Tseng","sequence":"additional","affiliation":[{"name":"Center for Space and Remote Sensing Research, National Central University, 32001 Taoyuan, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuchan","family":"Yi","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Science, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Woo, M. 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