Six channels of the Advanced Baseline Imager (ABI) onboard the Geostationary Operational Environmental Satellite (GOES) sense radiance in the visible and near infrared (VNIR) spectrum. Two ABI have been launched and in service, one with GOES-16 at 75.2oW and the other with GOES-17 at 137.2oW. Unlike the GOES infrared channels that have had onboard calibration since the 1970’s, ABI is the first GOES instrument that is equipped with onboard calibration for its RSB. This paper reviews the operational calibration of the ABI VNIR channels, including initial post-launch calibration, correction for elevation angle variation, and correction for azimuth (beta) angle variation. GOES-17 suffers from a compromised cooling subsystem such that the instrument temperature, including that for the VNIR Focal Plane Module, varies more than designed. The impact and mitigation of this thermal stress will also be described. Finally, GOES-18 will be launched in 1 March 2022. It is expected that some preliminary calibration results of GOES-18 will be available for discussion.
Declaimer: The scientific results and conclusions, as well as any views or opinions expressed herein, are those of the authors and do not necessarily reflect those of NOAA or the Department of Commerce.
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