Jian Mao , Di Hu , RuiGuang Li , ChangChen Wu , TieJun Cui
{"title":"Enhancing GNSS tropospheric delay corrections through an innovative lapse rate grid and adiabatic modelling","authors":"Jian Mao , Di Hu , RuiGuang Li , ChangChen Wu , TieJun Cui","doi":"10.1016/j.asr.2024.11.039","DOIUrl":null,"url":null,"abstract":"<div><div>Since measurements of meteorological parameters like air pressure, water vapor pressure, and temperature are typically not conducted at the receiving antenna’s height, accurate vertical adjustments are indispensable for the tropospheric delay calculation in GNSS applications. We developed an enhanced GPT3 model named as GPT3a, incorporating a new temperature lapse rate grid model and the adiabatic method. The capabilities of GPT3a in predicting atmospheric parameter profiles are assessed by comparison with radiosonde data, NCEP reanalysis data, and GNSS data. Compared with GPT3, IGPT, UNB3, and the constant model with a value of 6.5 K/km, the accuracy of the GPT3a is improved by 50 %, 26 %, 21 %, and 31 % respectively in predicting lapse rate. The RMSEs of GPT3a, GPT3 and IGPT, across temperature profiles (4.2 K, 10.7 K and 6.6 K, respectively), pressure profiles (5.7 hPa, 18.7 hPa and 6.8 hPa, respectively), and ZHD profiles (16.4 mm, 36.4 mm and 17.5 mm, respectively), demonstrate that GPT3a performs superiorly to the GPT3 and IGPT models. Moreover, in the GNSS-based water vapor retrieval, when there is a large height difference between GNSS sites and the model, the GPT3a obviously outperforms GPT3. In short, GPT3a can be used as an enhancement of GPT3 to support GNSS positioning, GNSS meteorology and atmospheric research, which extends the applicability of GPT3 beyond the Earth’s surface to airspace.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2696-2710"},"PeriodicalIF":2.8000,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advances in Space Research","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S027311772401161X","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
Since measurements of meteorological parameters like air pressure, water vapor pressure, and temperature are typically not conducted at the receiving antenna’s height, accurate vertical adjustments are indispensable for the tropospheric delay calculation in GNSS applications. We developed an enhanced GPT3 model named as GPT3a, incorporating a new temperature lapse rate grid model and the adiabatic method. The capabilities of GPT3a in predicting atmospheric parameter profiles are assessed by comparison with radiosonde data, NCEP reanalysis data, and GNSS data. Compared with GPT3, IGPT, UNB3, and the constant model with a value of 6.5 K/km, the accuracy of the GPT3a is improved by 50 %, 26 %, 21 %, and 31 % respectively in predicting lapse rate. The RMSEs of GPT3a, GPT3 and IGPT, across temperature profiles (4.2 K, 10.7 K and 6.6 K, respectively), pressure profiles (5.7 hPa, 18.7 hPa and 6.8 hPa, respectively), and ZHD profiles (16.4 mm, 36.4 mm and 17.5 mm, respectively), demonstrate that GPT3a performs superiorly to the GPT3 and IGPT models. Moreover, in the GNSS-based water vapor retrieval, when there is a large height difference between GNSS sites and the model, the GPT3a obviously outperforms GPT3. In short, GPT3a can be used as an enhancement of GPT3 to support GNSS positioning, GNSS meteorology and atmospheric research, which extends the applicability of GPT3 beyond the Earth’s surface to airspace.
期刊介绍:
The COSPAR publication Advances in Space Research (ASR) is an open journal covering all areas of space research including: space studies of the Earth''s surface, meteorology, climate, the Earth-Moon system, planets and small bodies of the solar system, upper atmospheres, ionospheres and magnetospheres of the Earth and planets including reference atmospheres, space plasmas in the solar system, astrophysics from space, materials sciences in space, fundamental physics in space, space debris, space weather, Earth observations of space phenomena, etc.
NB: Please note that manuscripts related to life sciences as related to space are no more accepted for submission to Advances in Space Research. Such manuscripts should now be submitted to the new COSPAR Journal Life Sciences in Space Research (LSSR).
All submissions are reviewed by two scientists in the field. COSPAR is an interdisciplinary scientific organization concerned with the progress of space research on an international scale. Operating under the rules of ICSU, COSPAR ignores political considerations and considers all questions solely from the scientific viewpoint.