DEPENDENCE OF INFRARED EMISSIVITY ON VIEW ZENITH ANGLE FOR NATURAL GROUND SURFACES

The present paper concentrates on investigating the dependence of emissivity on view zenith angle for natural ground surfaces, The in-situ measurements of emissivity have been made with dif ferent view zenith angles for several materials on the ground. The angular correction of infrared emissivity was made for land surfaces' temperature both inversed from satellite data and measured by groundbased radiometer. The comparison of the results inversed by AVHRR data with that measured by ground radiometer shows that the correction of the angular effect of emissivity can not be neglected for land surface temperature derived by remote sensing methods. In the case of very large viewing zenit hangles the angular correction is more important than emissivity correction itself.