{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T15:07:55Z","timestamp":1761664075220,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T00:00:00Z","timestamp":1593043200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key R&amp;D Program of China","award":["2017YFA0603103"],"award-info":[{"award-number":["2017YFA0603103"]}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41731069","41974002"],"award-info":[{"award-number":["41731069","41974002"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chinese Scholarship Council","award":["201706260151"],"award-info":[{"award-number":["201706260151"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Limited by the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) measurement principle and sensors, the spatial resolution of mass flux solutions is about 2\u20133\u00b0 in mid-latitudes at monthly intervals. To retrieve a mass flux solution in the Tibetan Plateau (TP) with better visual spatial resolution, we combined truncated singular value decomposition (TSVD) and Tikhonov regularization to solve for a mascon modeling. The monthly mass flux parameters resolved at 1\u00b0 are smoothed to about 2\u00b0 by truncating the eigen-spectrum of the normal equation (i.e., using the TSVD approach), and then Tikhonov regularization is applied to the truncated normal equation. As a result, the terms beyond the native resolution of GRACE\/GRACE-FO data are truncated, and the errors in higher degree and order components are dampened by Tikhonov regularization. In terms of root mean squared errors, the improvements are 27.2% and 12.7% for the combined method over TSVD and Tikhonov regularization, respectively. We confirm a decreasing secular trend with \u22125.6 \u00b1 4.2 Gt\/year for the entire TP and provide maps with 1\u00b0 resolution from April 2002 to April 2019, generated with the combined TSVD and Tikhonov regularization method.<\/jats:p>","DOI":"10.3390\/rs12122045","type":"journal-article","created":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T10:36:54Z","timestamp":1593081414000},"page":"2045","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["A Combined Use of TSVD and Tikhonov Regularization for Mass Flux Solution in Tibetan Plateau"],"prefix":"10.3390","volume":"12","author":[{"given":"Tianyi","family":"Chen","sequence":"first","affiliation":[{"name":"College of Surveying and Geo-informatics, Tongji University, Shanghai 200092, China"}]},{"given":"J\u00fcrgen","family":"Kusche","sequence":"additional","affiliation":[{"name":"Institute of Geodesy and Geoinformation, University of Bonn, Nussallee 17, 53115, Bonn, Germany"}]},{"given":"Yunzhong","family":"Shen","sequence":"additional","affiliation":[{"name":"College of Surveying and Geo-informatics, Tongji University, Shanghai 200092, China"}]},{"given":"Qiujie","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Geodesy and Geoinformation, University of Bonn, Nussallee 17, 53115, Bonn, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1007\/s10712-015-9338-y","article-title":"What can be expected from the GRACE-FO laser ranging interferometer for earth science applications?","volume":"37","author":"Flechtner","year":"2016","journal-title":"Surv. 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