Estimates and Zoning of reference evapotranspiration by FAO-Penman-Monteith (Case Study: North West of Iran)

Authors(2) :-Mokhtar Karami, Mehdi Asadi

Determination of evapotranspiration in many studies, including the hydrologic balance, design and management of irrigation systems, simulation of product and management of water resources is very important. For this purpose, the data required includes daily temperature, humidity, wind speed, solar radiation pressure and in the period 1990-2013 from the meteorological stations in the area is the area that includes 35 stations were taken. And to estimate evapotranspiration at the regional stations of the area we use Excel and GIS capabilities and its regression equation was obtained. To generalize stations in the region of interpolation we use methods IDW (Inverse Distance Weighting) and the relationship between height and evapotranspiration with a correlation coefficient of linear regression was used 0.52. The study results showed that the IDW method in more accurate than Linear regression relationship between height and evapotranspiration because it has lower RMSE (0.26). The total average reference evapotranspiration in the study area for the above mentioned methods is 988.657 and 1036 respectively and It was also found that the northern, eastern and lake basin, evapotranspiration intensity is more than the North-West, West, South-West and South-East and East of study area.

Authors and Affiliations

Mokhtar Karami
Faculty of Geography and Environmental Sciences, Hakim Sabzevari University, Sabzevar, I.R of Iran
Mehdi Asadi
Ph.D. Student Agricultural Meteorology, Hakim Sabzevari University, Sabzevar, I.R of Iran

Reference evapotranspiration, FAO - Penman-Monteith, zoning, linear regression

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Publication Details

Published in : Volume 2 | Issue 1 | January-February 2016
Date of Publication : 2016-02-25
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 210-216
Manuscript Number : IJSRSET162119
Publisher : Technoscience Academy

Print ISSN : 2395-1990, Online ISSN : 2394-4099

Cite This Article :

Mokhtar Karami, Mehdi Asadi, " Estimates and Zoning of reference evapotranspiration by FAO-Penman-Monteith (Case Study: North West of Iran), International Journal of Scientific Research in Science, Engineering and Technology(IJSRSET), Print ISSN : 2395-1990, Online ISSN : 2394-4099, Volume 2, Issue 1, pp.210-216, January-February-2016.
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