In orbit calibration of the ATSR-1 1 center dot 6 mu m channel using high resolution data from the JERS-1 (Fuyo-1) optical sensor

The 1.6 mu m channel of the Along Track Scanning Radiometer-1 (ATSR-1) does not benefit from a pre-launch or onboard digital count to spectral radiance calibration mechanism. This Letter outlines the results of a post-launch calibration procedure, accomplished by comparing near-coincident data from the uncalibrated ATSR-1 instrument onboard ERS-1 and the (calibrated) OPS instrument onboard JERS-1. These results show that the ATSR-1 1.6 mu m channel can be considered linear in response to incoming radiance and equations are produced that allow data from this channel to be calibrated in units of spectral radiance and/or spectral reflectance.