Comparing FY-3A and NOAA-18 Microwave Sounding Data with COSMIC GPS RO Data

In this study, we compare brightness temperature (BT) measurements for the upper troposphere and lower stratosphere from National Oceanic and Atmospheric Administration (NOAA) Advanced Microwave Sounding Unit measurements (AMSU-A/B) and Chinese FY-3A Microwave Temperature Sounding (MTS) instrument with the GPS radio occultation (RO) data from Constellation Observing System for Meteorology Ionosphere & Climate (COSMIC) over a one-month period (January 2010). The GPS RO temperature and moisture retrieval profiles are used as input to RTTOV9.3 to simulate microwave brightness temperatures at AMSU-A/B channels and FY-3A MTS channels. Global and monthly mean and standard deviations of BT differences between CSMIC GPS RO data and AMSU-A/B or FY-3A data are calculated. Excellent agreement was found between FY-3A and COSMIC GPS RO data, similar to that between AMSU-A and COSMIC GPS data. Geographical and weather dependence of the discrepancy between the satellite data and GPS RO data are analyzed. Based on the above comparison, a quality control procedure for the FY-3 MTS observations is developed. Results will be presented at the conference.