Saeed Jahanbakhsh; Majid Rezaee Banafshe; Marziyeh Esmaeelpour; Masoomeh Tadayoni
Volume 16, Issue 40 , September 2012, , Pages 25-46
Abstract
Accurate estimating of potential evapotranspiration is essential for many studies related to agriculture and water balance. This study was carried out with the aim of surveying models for estimating potential evapotranspiration in the southern basin of Aras river. For this purpose, the monthly data of ...
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Accurate estimating of potential evapotranspiration is essential for many studies related to agriculture and water balance. This study was carried out with the aim of surveying models for estimating potential evapotranspiration in the southern basin of Aras river. For this purpose, the monthly data of 6 stations including mean air temperature, minimum and maximum temperature, wind speed, sunshine hours, mean and minimum relative humidity were used in the statistical period of 20 years (1986-2005).
After reconstruction missing values and controlling stations for being reference (well irrigated) or non reference, potential evapotranspiration values were computed applying 9 methods (FAO- Penman- Monteith, Blanney-Criddle, Hargreaves-Samani, Makkink, Turc, ASCE standardized method, Kimberly- Penman, Penman and Priestly-Taylor) in REF-ET software. For determining best method, calculated potential evapotranspiration values were compared with evaporation pan values by using correlation coefficient and root mean square difference. Results indicated that there was significant correlation between Blanney-Criddle and pan evaporation values. Therefore, Blanney-Criddle model was selected as the best model for the study area. Afterwards, based on the above mentioned model and also the use of interpolation technique, the potential iso-evapotranspiration map was drawn for the southern basin of the ArasRiver.
