The Study Of Tasseled Cap Transformation And Regional Evapotranspiration Models Based On ASTER

Evapotranspiration is the largest and most difficult part to estimate in surface water circulation, and it also is an important process in interaction process between the land and atmosphere of land surface process. Its weightiness gets the recognition increasingly in the study of the global climate change. In many fields, the evapotranspiration have been applied.In this paper, firstly, we introduced the method about rotating the ASTER data using the interactively Tasseled Cap, and got the results representing the surface physical characters. Then, the SEBAL and TSEB modes were used in this research to calculate the actual evapotranspiration. The research results and conclusion were summarized as follows:1) The interactively Tasseled Cap method can reflect the surface physical characters well, especially in the condition of having the high resolution and multi-spectral remote sensing datum and the knowledge of the research site. Furthermore, its results is exact, its process is simply. It can be used in the classification and extraction of the land surface information.2) The results of the SEBAL model is better than that of TSEB, and the parameters used in SEBAL model are lesser, so this made the process fast. The TSEB model takes into account the thermal character differences between the vegetation and soil, but due to the restriction of the unmixing study methodology in this research, existence of the mixing pixels affected its veracity.How to integrate the results of the Tasseled Cap and the evapotranspiration models together to get more exact outcome will be study stress in the future.