Standard calibration procedure for IR sensors on spinning satellites. Volume 3: OTS and GEOS-2 in flight data analysis

An Earth radiance seasonal model derived from an infrared experiment flown on the ESRO 4 satellite in 1974 was verified using flight data from OTS and GEOS-2 satellites. The model, deduced by analysis of in flight measurements is compared with the NASA model based upon experiments and theoretical studies. The comparison between in flight and simulated data does not reveal a best model, but forms a basis for qualifying both IR Earth radiance representations for describing the long term variations which may affect IR pencil beam measurements. The tests show that visualizing the flight residuals is a very useful check for validating the in flight attitude estimate. Anomalies in the preflight calibration can be detected a posteriori.