{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T06:38:15Z","timestamp":1772951895021,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2019,3,24]],"date-time":"2019-03-24T00:00:00Z","timestamp":1553385600000},"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":["41804032"],"award-info":[{"award-number":["41804032"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41774019"],"award-info":[{"award-number":["41774019"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Key Laboratory of Geospace Environment and Geodesy, the Ministry of Education, Wuhan University","award":["17-01-11"],"award-info":[{"award-number":["17-01-11"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Research on total electron content (TEC) empirical models is one of the important topics in the field of space weather services. Global TEC empirical models based on Global Ionospheric Maps (GIMs) TEC data released by the International GNSS Service (IGS) have developed rapidly in recent years. However, the accuracy of such global empirical models has a crucial restriction arising from the non-uniform accuracy of IGS TEC data in the global scope. Specifically, IGS TEC data accuracy is higher on land and lower over the ocean due to the lack of stations in the latter. Using uneven precision GIMs TEC data as a whole for model fitting is unreasonable. Aiming at the limitation of global ionospheric TEC modelling, this paper proposes a new global ionospheric TEC empirical model named the TECM-GRID model. The model consists of 5183 sections, corresponding to 5183 grid points (longitude 5\u00b0, latitude 2.5\u00b0) of GIM. Two kinds of single point empirical TEC models, SSM-T1 and SSM-T2, are used for TECM-GRID. According to the locations of grid points, the SSM-T2 model is selected as the sub-model in the Mid-Latitude Summer Night Anomaly (MSNA) region, and SSM-T1 is selected as the sub-model in other regions. The fitting ability of the TECM-GRID model for modelling data was tested in accordance with root mean square (RMS) and relative RMS values. Then, the TECM-GRID model was validated and compared with the NTCM-GL model and Center for Orbit Determination in Europe (CODE) GIMs at time points other than modelling time. Results show that TECM-GRID can effectively describe the Equatorial Ionization Anomaly (EIA) and the MSNA phenomena of the ionosphere, which puts it in good agreement with CODE GIMs and means that it has better prediction ability than the NTCM-GL model.<\/jats:p>","DOI":"10.3390\/rs11060706","type":"journal-article","created":{"date-parts":[[2019,3,25]],"date-time":"2019-03-25T06:56:52Z","timestamp":1553497012000},"page":"706","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["A New Global Total Electron Content Empirical Model"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0054-6690","authenticated-orcid":false,"given":"Jiandi","family":"Feng","sequence":"first","affiliation":[{"name":"School of Civil and Architectural Engineering, Shandong University of Technology, Zibo 255000, China"},{"name":"Sate Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China"},{"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"}]},{"given":"Baomin","family":"Han","sequence":"additional","affiliation":[{"name":"School of Civil and Architectural Engineering, Shandong University of Technology, Zibo 255000, China"},{"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\/0000-0001-8861-5189","authenticated-orcid":false,"given":"Zhenzhen","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Civil and Architectural Engineering, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengtao","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1016\/j.asr.2012.09.039","article-title":"Evaluation of COMPASS ionospheric model in GNSS positioning","volume":"51","author":"Wu","year":"2013","journal-title":"Adv Space Res"},{"key":"ref_2","first-page":"142","article-title":"Evaluation on the precision of Klobuchar model for BeiDou navigation satellite system","volume":"39","author":"Zhang","year":"2014","journal-title":"Geomat. 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