Estimation of evapotranspiration for ungauged areas using MODIS measurements and GLDAS data

摘要

On base of Priestley-Taylor Equation combined with the Ts/NDVI space, namely, surface temperature-Normalized Difference Vegetation Index feature space, MODIS (Moderate Resolution Imaging Spectroradiometer) products and GLDAS(Global Land Data Assimilation System) meteorological data are introduced to calculate evapotranspiration (ET) in ungauged basins. The whole procedure is independent of field data. It was then applied to Tekesi River Basin to estimate evapotranspiration from 2006 to 2009. Validation has been made by comparing the estimated ET with the Bowen Ratio measurements from 15th, August to 15th, September in 2009 at Zhaosu site, which shows good agreement between the estimated ET and the observed.