Evapotrative Flux Estimation Over Indian Region Using S-NPP Optical and Thermal Data

Evapotranspiration, a major component of the hydrological cycle, is responsible for the movement of water from land to atmosphere. Accurate estimation of evapotranspiration (ET) is essential for efficient crop water management, drought assessment, and irrigation scheduling. Spatial ET can be estimated using different surface energy-balance based models. In this study, the contextual interpretation of remotely sensed land surface temperature and vegetation index is used in the Priestley-Taylor (P-T) algorithm to derive Actual Evapotranspiration (AET). This paper discusses the experiences and elucidates the challenges in generating daily AET product. In order to assess the performance of satellite derived AET estimation, the results are validated using open path eddy covariance system measurement at CICR, Nagpur. Satellite derived AET product is compared with AET observation from flux tower data for the period April 2019 – March 2020. The results reveal R ² value of 0.77 for 10-day average interval between estimated AET and ground observations for cloud free days.