Evaluation of " Experimental Methods in Estimation of Large-Scale Actual Annual Evapotranspiration" using " Estimated Evapotranspiration from SEBAL" for Neyshabor Plain

According to Limited water resources in the country, Management of water resources as a strategy, it is essential for the crisis. For correct and scientific management of water resources that are needed A better understanding and knowledge of the complex collection of interactions associated with water in a water balance catchment. Evapotranspiration is one of the most important components of the water balance that it is difficult to measure the actual rate And have limited methods. In this study tried to achieve accurate estimates of actual evapotranspiration in catchment-year scale by using remote sensing method (SEBAL). To accomplish this, firstly using meteorological data and the SPI Index Years 84-83, 85-84 and 87-86 Were determined As the wet, normal and dry years Respectively. Then it was calculated actual evapotranspiration for Neishabour plain in catchment-year scale by using MODIS satellite images and SEBAL method. The results were compared with the results of the SWAT model that is showed good accuracy. Due to the purpose of this study is to provide an accurate, simple and inexpensive estimate for actual evapotranspiration in catchment-year scale, from the calibration relationship, Young's equation for the entire basin with RMSE= 28.3 mm and R2 = 0.90 and abcd equation for the plain with RMSE= 16.24 mm and R2 = 0.90, and Young's equation for the mountain with RMSE= 19.37 mm and R2 = 0.90 estimate The best response. Of course The results of Zhang’s and Fu’s equations were similar to Young's equation and there are a few differences