Open AccessCombining radio occultation refractivities and IR/MW radiances to derive temperature and moisture profiles: A simulation study plus early results using CHAMP and ATOVS
Author(s) -
Borbás Éva,
Menzel W. Paul,
Li Jun,
Woolf Harold M.
Publication year - 2003
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2003jd003386
Subject(s) - radiosonde , radio occultation , tropopause , environmental science , troposphere , global positioning system , remote sensing , brightness temperature , meteorology , satellite , atmospheric infrared sounder , numerical weather prediction , occultation , depth sounding , precipitable water , brightness , water vapor , geology , computer science , geography , physics , telecommunications , oceanography , astronomy , optics
This paper examines whether the Global Positioning System radio occultation (GPS/RO) measurements of the tropopause region improve tropospheric profile retrievals from infrared and microwave radiometric measurements with the Advanced TIROS Operational Vertical Sounder (ATOVS) on current National Oceanic and Atmospheric Administration (NOAA) polar orbiting satellites and with the future high spectral resolution infrared measurements from the Cross‐track Infrared Sounder (CrIS) planned for the NOAA Polar Orbiting Environmental Satellite System (NPOESS). The paper presents a simulation study wherein statistical regressions are used to infer temperature and moisture retrievals from ATOVS or CrIS brightness temperatures and GPS/RO refractivity data. The ATOVS and GPS/RO combination yields tropospheric profiles in better agreement with radiosondes than profiles inferred from either system alone; GPS/RO improves ATOVS temperature retrievals around the tropopause by 0.8 K and ATOVS tropospheric moisture retrievals by 2.5%. When the infrared measurements are improved to CrIS quality, with over 1000 spectral measurements, the addition of GPS/RO improves temperature retrieval agreement with radiosondes by 0.4 K around and above the tropopause. The paper also presents results from combining real GPS/RO (CHAMP, Challenging Minisatellite Payload) and sounder (ATOVS) data. CHAMP data are evaluated against collocated radiosonde and Numerical Weather Prediction model profiles. Using CHAMP data to establish a regression relationship, real GPS/RO data are found to improve the ATOVS temperature retrievals by 0.5 K near the tropopause.