{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,25]],"date-time":"2026-01-25T02:20:55Z","timestamp":1769307655696,"version":"3.49.0"},"reference-count":30,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,16]],"date-time":"2021-02-16T00:00:00Z","timestamp":1613433600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["109-2111-M-008-026"],"award-info":[{"award-number":["109-2111-M-008-026"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["109-2111-M-008-025"],"award-info":[{"award-number":["109-2111-M-008-025"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["109-2625-M-008-013"],"award-info":[{"award-number":["109-2625-M-008-013"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This study investigates the Global Navigation Satellite System (GNSS) radio occultation (RO) data from FORMOSAT-7\/COSMIC-2 (FS7\/C2), which provides considerably more and deeper profiles at lower latitudes than those from the former FORMOSAT-3\/COSMIC (FS3\/C). The statistical analysis of six-month RO data shows that the rate of penetration depth below 1 km height within \u00b145\u00b0 latitudes can reach 80% for FS7\/C2, significantly higher than 40% for FS3\/C. For verification, FS7\/C2 RO data are compared with the observations from chartered missions that provided aircraft dropsondes and on-board radiosondes, with closer observation times and distances from the oceanic RO occultation over the South China Sea and near a typhoon circulation region. The collocated comparisons indicate that FS7\/C2 RO data are reliable, with small deviations from the ground-truth observations. The RO profiles are compared with collocated radiosondes, RO data from other missions, global analyses of ERA5 and National Centers for Environmental Prediction (NCEP) final (FNL), and satellite retrievals of NOAA Unique Combined Atmospheric Processing System (NCAPS). The comparisons exhibit consistent vertical variations, showing absolute mean differences and standard deviations of temperature profiles less than 0.5 \u00b0C and 1.5 \u00b0C, respectively, and deviations of water vapor pressure within 2 hPa in the lower troposphere. From the latitudinal distributions of mean difference and standard deviation (STD), the intertropical convergence zone (ITCZ) is evidentially shown in the comparisons, especially for the NUCAPS, which shows a larger deviation in moisture when compared to FS7\/C2 RO data. The sensitivity of data collocation in time departure and spatial distance among different datasets are presented in this study as well.<\/jats:p>","DOI":"10.3390\/rs13040717","type":"journal-article","created":{"date-parts":[[2021,2,16]],"date-time":"2021-02-16T05:02:14Z","timestamp":1613451734000},"page":"717","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["An Analysis Study of FORMOSAT-7\/COSMIC-2 Radio Occultation Data in the Troposphere"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4428-7643","authenticated-orcid":false,"given":"Shu-Ya","family":"Chen","sequence":"first","affiliation":[{"name":"GPS Science and Application Research Center, National Central University, Taoyuan 32001, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1725-4405","authenticated-orcid":false,"given":"Chian-Yi","family":"Liu","sequence":"additional","affiliation":[{"name":"GPS Science and Application Research Center, National Central University, Taoyuan 32001, Taiwan"},{"name":"Center for Space and Remote Sensing Research, National Central University, Taoyuan 32001, Taiwan"},{"name":"Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan"}]},{"given":"Ching-Yuang","family":"Huang","sequence":"additional","affiliation":[{"name":"GPS Science and Application Research Center, National Central University, Taoyuan 32001, Taiwan"},{"name":"Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan"}]},{"given":"Shen-Cha","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan"}]},{"given":"Hsiu-Wen","family":"Li","sequence":"additional","affiliation":[{"name":"GPS Science and Application Research Center, National Central University, Taoyuan 32001, Taiwan"}]},{"given":"Po-Hsiung","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Atmospheric Sciences, National Taiwan University, Taipei 10617, Taiwan"}]},{"given":"Jia-Ping","family":"Cheng","sequence":"additional","affiliation":[{"name":"Central Weather Bureau, Taipei 10048, Taiwan"}]},{"given":"Cheng-Yung","family":"Huang","sequence":"additional","affiliation":[{"name":"National Space Organization, National Applied Research Laboratories, Hsinchu 30078, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"E1107","DOI":"10.1175\/BAMS-D-18-0290.1","article-title":"The COSMIC\/FORMOSAT-3 radio occultation mission after 12 years","volume":"101","author":"Ho","year":"2020","journal-title":"Bull. 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