Shahzad Sultan, Iftikhar Ahmad


Information on evaporation and transpiration from the agricultural field is an important requirement to manage water resources efficiently. The estimation of evapotranspiration through field observation is a laborious and time taking exercise. Current study gives estimation of regional scale evapotranspiration using remotely sensed data and ground based data for central Punjab in Pakistan. Surface Energy Balance Algorithm for Land (SEBAL) has been used to estimate actual evapotranspiration (ETa). SEBAL uses only seven bands (visible, near infrared and thermal infrared) of the Landsat7-ETM+ satellite sensor to estimate per pixel value of actual ETa .Ground based data is also synergized with the satellite data to enhance the validity of the results. The results reveal that using SEBAL model to estimate ETa is an appropriate method in Faisalabad & surroundings.

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