MODELING VERTICAL HEAT AND WATER FLUXES FROM RIVER BASIN AREA WITH AVHRR/NOAA-BASED INFORMATION ON LAND SURFACE CHARACTERISTICS

摘要

The model of vertical water and heat transfer in the "soil-vegetation-atmosphere" system (SVAT) for river basin accounting land surface heterogeneities has been developed. The capabilities have been investigated to replace several ground-measured land surface characteristics used as the model parameters and variables by satellite-derived ones while calculating evapotranspiration and other components of water balance. For these aims the methods and algorithms have been developed and tested for cloud-free AVHRR/NOAA data processing that provide the retrieval of land skin brightness temperature, air foliage temperature, efficient land surface temperature and emissivity, vegetation index, vegetation cover fraction, leaf area index. Model experiments performed with ground-based and satellite-derived estimates of the latter two characteristics have demonstrated closeness of the model and satellite estimates of named temperatures and practical coincidence of calculated and observed water balance components. These results give evidence for the applicability of above satellite-derived estimates to calculate the vertical water and heat fluxes especially for the territories where surface observations are sparse.