Diagnosis of regional evaporation by remote sensing to support irrigation performance assessment

Performance assessment indicators, being functions of evaporation, are useful tools to evaluate the actual functioning of an irrigation system. The spatial variability of evaporation in large irrigation schemes makes its determination with conventional point measurements almost impossible. A new remote sensing evaporation parametrization algorithm was tested with high-resolution Landsat Thematic Mapper data for the Eastern Nile Delta, Egypt. The actual evaporation was used to express the uniformity of crop water use, which is related to the equity of water distribution. Improved information on actual crop growth conditions through remote sensing gives insight into the planning of real-time and seasonal irrigation water deliveries