Estimation of Actual Evapotranspiration in the Urmia Lake Watershed Using SEBS Remote Sensing Algorithm and NOAA Satellite Images

Evapotranspiration is one of the main components of the water balance in each region and also one of the key factors for proper planning and improving water efficiency in Faryab lands. Due to covering large areas, satellite images have better application for regional studies than weather station data to overcome the spatial constraints of Point method. Therefore, the purpose of this study is to estimate the actual evapotranspiration of Urmia lake watershed using the SEBS remote sensing and AVHR sensor images. First, 248 images were obtained from AVHR sensor and NOVAA satellite and after the investigating of non-cloudiness are used in the period of 1998-2009. In order to making the estimation of evaporation more accurate, the case study divided into three parts: Saqes,Urmia ,and Tabriz. Actual evaporation has been calculated accompanied with the agricultural land use maps and compared with the pure irrigation requirement of the area. By calculating the evaluation indices of the model for Tabriz plain, RMSE and coefficient of determination were 10.89 and 0.79 respectively. The results showed that the trend of evapotranspiration changes has consistency with the pure irrigation requirement and the SEBS model has a good accuracy in the estimating of actual evapotranspiration for agricultural lands in different parts of the Urmia lake watershed