期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:2006
卷号:XXXVI Part 4
出版社:Copernicus Publications
摘要:Energy and mass transport between and within soils, canopies, and the atmosphere is an area of increasing interest in hydrology and meteorology. Evapotranspiration (ET) can account for over 90% of the precipitation, making accurate knowledge of the surface energy balance particularly critical. This paper deals with the evapotranspiration modeling in the forest ecosystem and gives evapotranspiration maps as output. Since, the Energy exchange through the process of evapotranspiration is highly dynamic and depends on a large number of factors, it has been substantially highlighted in this paper. Here, three process-based ET estimation models based on the canopy temperature, derived from satellite thermal channels and the weather parameters, have been described and compared for forest ecosystem. LST and emissivity required for the models are estimated by another sub-model called Temperature-Emissivity separation algorithm using thermal channels of ASTER. The VNIR and SWIR bands of ASTER are used for the estimation of albedo. Net radiation has been estimated using the inputs such as LST, emissivity, albedo, sunshine duration and ambient temperature. Finally, a package has been developed using 'C' language for executing the models proposed
关键词:Evapotranspiration; LST; Surface emissivity; albedo; net radiation; sensible heat flux