A Technique to Estimate the Emissivity of a Volcanic Area at Wavelengths of Avhrr Tir Channels



Advances in Space Research
Volume 26, Issue 7 , 2 October 2000, Pages 1085-1088

In this work a study about the emissivity and atmospheric effects related to the Land Surface Temperature determination is shown. For this purpose, a particular test area situated over 2300 m altitude in a volcanic terrain at Las Caņadas National Park (Canary Islands) has been selected. In this zone, the prevailing trade winds system make the highest water vapor content to be concentrated under this altitude. In order to analyze the effect of this absorbent gas on the atmospheric correction, a preliminary study using radiosounding profiles and radiances simulated with MODTRAN radiance/transmittance code is made. The results of this analysis suggest that if its contribution is negligible or can be easily parameterized, the effective emissivity could be calculated by tuning its value in the radiative transfer equation and using a sufficiently representative number of in situ measurements together with the corresponding coincident satellite measurements.