Drought prediction using the Along Track Scanning Radiometer (ATSR2) on board ERS2 satellite

摘要

Frequent monitoring and estimation of the areas under drought danger is important for agriculture, hydrology, weather, natural hazards and crop yield prediction. The evaporation fraction, calculated as a function of the evapotranspiration and net radiation over heterogeneous land surface, is used as a drought indicator in this study, where areas with low evaporation fraction are under drought danger. A two-source energy balance model has been applied to calculate the fluxes arising from the heterogeneous target, vegetation and soil. The fluxes have been retrieved from the Along Track Scanning Radiometer (ATSR2) on board the European Research Satellite (ERS2). The main advantage of the algorithm is the separation of the canopy and soil fluxes. The fluxes have been calculated as a function of the aerodynamic temperatures of the components of the surface (vegetation and soil), retrieved from the ATSR2 satellite data. The relationship between canopy biophysical properties and evaporation are examined, using the ATSR2 observations. All variables are retrieved from the ATSR2 satellite data corrected for the atmospheric effects. The algorithm for drought prediction has a long-term application for processing data from the ATSR2/ERS2, the Advanced Along Track Scanning Radiometer (AATSR) on board ENVISAT, ASTER/Terra/NASA and the future high resolution ESA/Land Surface mission (SPECTRA).