Calibration of GOES-5 and GOES-6 VISSR/VAS short-wavelength channels

The GOES-5 and GOES-6 VISSR/VAS short wavelength channels are calibrated for the periods from October 1983 through July 1984 (GOES-5) and from October 1983 through January 1985 (GOES-6). The White Sands Monument area in New Mexico and space are used as calibration targets. The radiance directed to the satellite from the surface target is computed using a radiative transfer model. Measured surface and atmospheric properties are used as input to the model. The coefficients relating the brightness count (CN) to the incident radiance R (R=aCNsq+b) are found to vary little (10%) from the mean values for the entire study periods, indicating the good behavior of the instruments in orbit. The mean values are 0.0083 W/sqm/sr/micron (GOES-5) and 0.0089 W/sqm/sr/micron (GOES-6) for a; and -5.2 (GOES-5) and -7.1 (GOES-6) for b.