Comparison Result of Evaluating Actual Evapotranspiration of Crops and Orchards by SEBS and SEBAL Alghorithms (Case study: Qazvin plain)

Water crisis is one of the biggest challenges facing today’s societies so evaluating actual crops evapotranspiration is really vital in water management, specially in areas facing with water scarcity. There are different methods for estimating evapotranspiration, but their performance is different in each climate.
Accordingly, the purpose of this study is to evaluate actual evapotranspiration in Qazvin plain base on satellite imageries of MODIS, Landsat7 (ETM+) and surface energy balance alghorithms, SEBAL and SEBS. The results were evaluate and compare with Lysimetric data in 2001 and 2002.
The statistic results shows that, by using ETM+ sensor in Landsat7 satellite, SEBAL alghorithms with regression coefficient (r=0/85), RMSE=1/29 mm/day, ESE=0/11 mm/day and SEBS alghorithms in MODIS imageries with regression coefficient (r=0/88), RMSE=1/55 mm/day, CRM=0/14 and ESE=1/6 mm/day would have more accurate results.
Base on statistics analysis results and satellite imageries, in evaluating actual evapotranspiration the SEBAL alghorithms is more accurate and satisfying.