Estimation of Evapotranspiration through Satellite Remote Sensing

Abstract

Evapotranspiration (ET) constitutes an important component of the water fluxes in the Hydrosphere and the atmosphere. Fresh water is most precious natural resource and the practical management of this resource is one of our utmost challenges. An understanding regarding the natural systems and the physical laws that govern each component of the hydrologic cycle is very important for the water resource manager. Remote sensing is an excellent tool for such monitoring as it provides information related to mass and energy transfers and particularly to evapotranspiration fluxes. In particular, the evaporation processes from the various surfaces of the earth need to be understood in order to achieve a sustainable development of our water resources. The combination of two separate processes by which water drives to the atmosphere are evaporation from the soil and transpiration from vegetation commonly referred as evapotranspiration (ET). ET has important implications in modeling regional and global climate and the hydrological cycle as well as assessing environmental stress on natural and agricultural ecosystem. The capability to predict levels of ET (using SEBAL model) would be a valuable asset for water resource managers. ET is a good indicator of irrigation effectiveness and total water consumption from vegetation. Evapotranspiration information is useful for irrigation supply planning, water rights regulation and river basin hydrologic studies.