COMPARISON OF SEBAL-BASED EVAPOTRANSPIRATION WITH LYSIMETERIC DATA

摘要

There are several algorithms for estimation of crop evapotranspiration such as SEBALrn(Surface Energy Balance Algorithm for Land). In this study, SEBAL was used for estimationrnand evaluation of agricultural crop evapotranspiration by using of MODIS, NOAA, and ASTERrnimaginary and meteorological data of Kerman province and consequently results wererncompared with lysimeteric data. Due to hot and dry climate of the study area, optimum valuernof L (soil adjustment factor) had to be determined. Results show that increasing of L causesrnincreasing of estimated evapotranspiration and minimum errors occurred when L equals to 1.rnIn this case, RMSE was 0.29 and 0.76 by the use of MOSIS and NOAA imaginary respectively.rnRelative error of evapotranspiration estimation by SEBAL from MODIS, NOAA and ASTERrnimages are 10%, 13% and 3.57% respectively. Errors are introduced by the difference in timernof irrigation and different characteristics of cultivated plant in lysimeter data, adjacent farms,rnaround area and interpolation of hourly meteorological data.