Mapping evapotranspiration in the Indus Basin using ASTER data

摘要: Conventional methods that use point measurements to estimate evapotranspiration are representative only of local areas and cannot be extended large because heterogeneity landscape. To overcome this difficulty, remote sensing has proven the most suitable approach for area estimation data can provide parameters such as radiometric surface temperature, albedo vegetation index. The is more prominent in Indus Basin than 80% farmers have land holdings less 4 ha, within these holdings, two or three different crops usually grown. limitation based procedures number crop-specific climatic parameters, which not difficult obtain but also require considerable field work, equipment therefore involve much expenditure. purpose study was present a simple methodology requires minimum ground observations test reliability Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) Basin. on energy balance sensible latent heat fluxes by combining remotely sensed from ASTER with common meteorological data. various components were computed during satellite overpass 24-h integrated derived full scene acquired over lower Rechna doab region brightness temperatures thermal band 13 NDVI VNIR bands ASTER. Evapotranspiration values maize Basin, estimated using at Shahkot, Jaranwala Satiana locations, 2.05, 2.77 2.32 mm day-1, respectively. compared locations CROPWAT software found close agreement.