Estimation of evapotranspiration and photosynthesis by assimilation of remote sensing data into SVAT models

Estimation of evapotranspiration and photosynthesis from remote sensing data frequently use soil-vegetation-atmosphere transfer models (SVAT models). These models compute energy and mass transfer using descriptions of turbulent, radiative, and water exchanges, as well as a description of stomatal control in relation with water vapor transfers and photosynthesis. Remote sensing data mall provide information that is useful for driving SVAT models (e.g., surface temperature, surface soil moisture, canopy structure, solar radiation absorption, or albedo). Forcing or recalibration methods may be employed to combine remote sensing data and SWAT models. In this article a review of SVAT models and remote sensing estimation of energy and mass fluxes is presented. Examples are given based on our work on two different SVAT models. Eventually, some of the difficulties in the combined use of multispectral remote sensing data and SVAT models are discussed. (C) Elsevier Science Inc., 1999.