{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T17:37:31Z","timestamp":1773855451223,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2022,7,12]],"date-time":"2022-07-12T00:00:00Z","timestamp":1657584000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["U1831116"],"award-info":[{"award-number":["U1831116"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["11903064"],"award-info":[{"award-number":["11903064"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["2018YFC1406104"],"award-info":[{"award-number":["2018YFC1406104"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["2020YFA0713501"],"award-info":[{"award-number":["2020YFA0713501"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["NO.KFKT_201906"],"award-info":[{"award-number":["NO.KFKT_201906"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key R&amp;D Plan","award":["U1831116"],"award-info":[{"award-number":["U1831116"]}]},{"name":"National Key R&amp;D Plan","award":["11903064"],"award-info":[{"award-number":["11903064"]}]},{"name":"National Key R&amp;D Plan","award":["2018YFC1406104"],"award-info":[{"award-number":["2018YFC1406104"]}]},{"name":"National Key R&amp;D Plan","award":["2020YFA0713501"],"award-info":[{"award-number":["2020YFA0713501"]}]},{"name":"National Key R&amp;D Plan","award":["NO.KFKT_201906"],"award-info":[{"award-number":["NO.KFKT_201906"]}]},{"name":"opening project of Shanghai Key Laboratory of Space Navigation and Positioning Techniques","award":["U1831116"],"award-info":[{"award-number":["U1831116"]}]},{"name":"opening project of Shanghai Key Laboratory of Space Navigation and Positioning Techniques","award":["11903064"],"award-info":[{"award-number":["11903064"]}]},{"name":"opening project of Shanghai Key Laboratory of Space Navigation and Positioning Techniques","award":["2018YFC1406104"],"award-info":[{"award-number":["2018YFC1406104"]}]},{"name":"opening project of Shanghai Key Laboratory of Space Navigation and Positioning Techniques","award":["2020YFA0713501"],"award-info":[{"award-number":["2020YFA0713501"]}]},{"name":"opening project of Shanghai Key Laboratory of Space Navigation and Positioning Techniques","award":["NO.KFKT_201906"],"award-info":[{"award-number":["NO.KFKT_201906"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Global Navigation Satellite System (GNSS) signals generate slant tropospheric delays when they pass through the atmosphere, which is recognized as the main source of error in many spatial geodetic applications. The zenith tropospheric delay (ZTD) derived from radio occultation data is of great significance to atmospheric research and meteorology and needs to be assessed in the use of precision positioning. Based on the atmPrf, sonPrf, and echPrf data from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Data Analysis and Archiving Center (CDAAC) from 1 January to 31 December 2008 and 2012, we obtained the ZTDs of the radio occultation data (occZTD) and the corresponding radiosonde (sonZTD) and ECWMF data (echZTD). The ZTDs derived from ground-based global positioning system (GPS) observations from the International GNSS Service (IGS) were corrected to the lowest tangent point height of the matched radio occultation profile by the barometric height formula (gnsZTD). The statistical results show that the absolute values of the bias between occZTD and echZTD, sonZTD, or gnsZTD are less than 5 mm, and the standard deviations are approximately 20 mm or less, indicating that occZTD had significant accuracy in the GNSS positioning model even when the local spherical symmetry assumption error was introduced when the Abel inversion algorithm was used to obtain the refractive index profile of atmPrf. The effects of the horizontal\/vertical matching resolution and the variation in the station height\/latitude on the biases of occZTD and gnsZTD were analyzed. The results can be used to quantify the performance of radio occultation data for tropospheric delay error correction in dynamic high-precision positioning.<\/jats:p>","DOI":"10.3390\/s22145209","type":"journal-article","created":{"date-parts":[[2022,7,12]],"date-time":"2022-07-12T23:02:01Z","timestamp":1657666921000},"page":"5209","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Assessment of ZTD Derived from COSMIC Occultation Data with ECWMF, Radiosondes, and GNSS"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7989-7521","authenticated-orcid":false,"given":"Naifeng","family":"Fu","sequence":"first","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mingbo","family":"Jiang","sequence":"additional","affiliation":[{"name":"Beijing Institute of Applied Meteorology, Beijing 100029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fenghui","family":"Li","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peng","family":"Guo","sequence":"additional","affiliation":[{"name":"Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunping","family":"Hou","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mengjie","family":"Wu","sequence":"additional","affiliation":[{"name":"Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianming","family":"Wu","sequence":"additional","affiliation":[{"name":"Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1145-234X","authenticated-orcid":false,"given":"Zhipeng","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liang","family":"Kan","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1007\/s10291-012-0291-7","article-title":"V Estimation and Evaluation of Hourly Updated Global GPS Zenith Total Delays over Ten Months","volume":"17","author":"Dousa","year":"2013","journal-title":"GPS Solut."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1007\/s00190-010-0434-y","article-title":"Multi-Technique Comparison of Troposphere Zenith Delays and Gradients during CONT08","volume":"85","author":"Teke","year":"2011","journal-title":"J. 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