Comparison of in situ, aircraft- and satellite-derived surface reflectances in Flevoland (The Netherlands) : a validation experiment

In order to evaluate a complete atmospheric correction method for multispectral spaceborne imagery a validation campaign was set up in one of the Dutch polders (Eastern Flevoland). A ground based radiometer measured total and diffuse spectral irradiance simultaneous with TM data acquisition for purposes of atmospheric correction of observed satellite radiances. The experiment included the use of data of the Dutch airborne scanner CAESAR to compare measured reflectances from several altitude levels. To assess the surface reflectance factors in the test area a hand held field radiometer was used. Reference panels with known reflectances served for calibration of in situ and airborne data. Differences between satellite derived reflectances and ground based reflectances were quite small. Somewhat larger deviations occurred in airborne derived reflectances, which could not accurately be explained because of insufficient knowledge of some instrumental factors, e.g. field radiometer spectral response.