Comparing Different Processes for Mapping Reference Evapotranspiration in Iran

Document Type : Research Paper


1 M.Sc. in Irrigation and Drainage, Department of Water Engineering, Faculty of Water and Soil, University of Zabol, Iran.

2 Associate Professor, Department of Water Engineering, Faculty of Water and Soil, University of Zabol, Iran

3 Associate Professor, Department of Water Engineering, Faculty of Water and Soil, University of Zabol, Iran.

4 Faculty member, Department of Water Engineering, Faculty of Water and Soil, University of Zabol, Iran.


Estimation of reference evapotranspiration (ET0) is essential to determine water requirements of crops. In other words, to regionalize ET0 to a large area, some interpolation methods should be used (Goovaerts, 1997). A key parameter which may influence the proper performance of interpolattion methods, is the sequence of ET0 estimation process (Mardikis et al., 2005; Vilanova et al., 2012). That is why using some auxillary variables cross correlated with the main variable, could significantly improve the accuracy of interpolation methods. Therefore, this study aims to analyze the estimation process sequences while investigating spatial variability of annual and monthly ET0 in Iran. A comprehensive comparison of spatial interpolators is performed. Elevation is also used as a secondary variable in multivariate methods.


Main Subjects

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Volume 43, Issue 3
October 2020
Pages 17-31
  • Receive Date: 07 December 2016
  • Revise Date: 22 November 2017
  • Accept Date: 26 November 2017
  • Publish Date: 22 September 2020