Radiometric Calibration Performance of GOES-16/17 Advanced Baseline Imagers (ABI)

The Advanced Baseline Imager (ABI) is the primary instrument onboard NOAA’s current Geostationary Operational Environmental Satellites (GOES), GOES-16 (GOES East) and GOES-17 (GOES West). These 16-band instruments are collecting imagery critical to the National Weather Service for accurate weather nowcasting and forecasting over the Earth’s Western Hemisphere. While GOES-16 operates as designed, the partial failure of the GOES-17 ABI cooling system leads to a set of different operational configurations that optimizes the instrument performance under the circumstances. Since GOES-17 ABI became operational in February 2019, several major Ground System (GS) updates have been successfully implemented to improve the ABI radiance quality of the solar reflective and infrared (IR) bands. The impacts of the GS updates on radiance and image quality were intensively validated and carefully monitored using different methods. This study is to report the radiometric calibration performance after each major update. The update of the scan mode in April 2019 reduces the calibration difference between the swaths within the timeline for the GOES-17 IR bands. The predictive calibration (pCal) algorithm implemented in July 2019 significantly improves the calibration accuracy for the GOES-17 IR data when they are available during the period of unstable focal plane module (FPM) temperature, and thus greatly reduces the calibration error at night. After several solar calibration updates to both ABIs from April to June 2019, the overall difference is less than 5% for all the solar reflective bands as compared to the corresponding channels of S-NPP Visible Infrared Imaging Radiometer Suite (VIIRS). Details will be reported in the meeting