Validation of CrIMSS EDR products with matched ECMWF analysis, RAOB Measurements, and IASI retrievals

Atmospheric Vertical Temperature Profiles (AVTP), Atmospheric Vertical Moisture profiles (AVMP), and other Environmental Data Records (EDRs) retrieved by the Cross-track Infrared Sounder and Advanced Technology Microwave Sounder (CrIMSS) EDR algorithm were all evaluated using matched European Center for Medium-Range Weather Forecasts (ECMWF) analysis fields, radiosonde (RAOB) measurements, and the retrieval products from Infrared Atmospheric Sounder Interferometer (IASI) observations. The proxy CrIS and ATMS Sensor Data Records (SDRs) needed to generate CrIMSS EDR products were derived for the “Focus Day,” October 19, 2007, using IASI, Advanced Microwave Sounding Unit (AMSU) and Microwave Humidity Sounder (MHS) observations, respectively. Similarly, using a collocated data set of IASI/AMSU-A/MHS observations, ECMWF analysis fields, and global RAOB measurements, proxy CrIS/ATMS SDRs were generated at RAOB locations for 15 days (May 1-15, 2008) to derive CrIMSS EDR products on validation subsets of data (~300 RAOBs per day distributed globally). The empirical bias tuning procedure, needed to account for the differences in the forward models used in the generation of ATMS proxy brightness temperatures and CrIMSS EDR algorithms, was implemented. The CrIMSS AVTP and AVMP products were generated for 236 granules of data for the focus day and for the global RAOB collocated data set. Using the ECMWF and/or RAOB measurements as the truth, bias and RMS differences were computed for the CrIMSS EDR and IASI retrieval products for the tropics, midlatitude, and polar regions, and for ‘land', ‘sea', ‘all' categories. The results of the evaluation reveal that the empirical bias-tuning procedure applied to the CrIMSS algorithm helps reduce the biases seen in the CrIMSS microwave-only retrieval. Evaluation of the CrIMSS infrared plus microwave AVMP and AVTP retrievals reveals reasonable agreement with the ECMWF and RAOB measurements and demonstrate at-launch readiness to characterize the CrIMSS EDR products. Further analyses of CrIMSS AVTP and AVMP products in conjunction with retrieved IR spectral emissivities and cloud-clearing parameters are in progress and will be presented at the conference.