Natural Resources and Conservation Vol. 2(2), pp. 25 - 32
DOI: 10.13189/nrc.2014.020202
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Regionalization Approach for Modeling of Monthly Evaporation Based on Cluster Analysis

Hossein Malekinezhad ^*
Yazd University, Yazd, Iran

ABSTRACT

Among interesting Climatic Parameters (CPs) of different climates, it may be asserted that evaporation has received a particular attention. The present study, by considering 14 stations in arid central and southern parts of Iran, has tried to determine the most important factors affecting evaporation through using Factor Analysis (FA). At first, by conducting Cluster Analysis (CA) through Minitab software, Homogeneous Regions (HRs) separated at the investigating areas. Then, the relation between climatic factors and evaporation on the basis of monthly routine was obtained in each region. Finally, by the help of accomplished regression equations, evaporation was calculated and MAE or RMSE statistics were applied to determine the precision of each relation. The results show that, firstly, factor analysis is an appropriate method for determining climatic parameters affecting evaporation in the regions. Secondly, as far as the relation between independent parameters and evaporation and priority of the main factors has been proved previously, multiple regressions may be used with great confidence to calculate evaporation and consequently evapotranspiration. The results also indicate that the difference between maximum and minimum temperatures (Tmax – Tmin), Tmax and the difference between maximum and minimum relative humidity (Hmax – Hmin) are, respectively, the main factors which influence the evaporation value at the Homogeneous Region (HR1) which is spread along Iran's water borders having a warm and humid climate. Generally, the Temperature Related Parameters (TPR) including Tmax – Tmin, Tmax, Tmin and Tmean at the HR1 are found as the main factors affecting evaporation. At the HR2 and HR3, wind speed, Tmax and Hmax – Hmin are identified as the main parameters and cloudiness as the second one. The results show that the wind speed and the cloudy times of day have a more effective role in the amount of evaporation rather than the temperature related factors.

KEYWORDS
Evaporation, Cluster Analysis, Multiple regressions, Evapotranspiration, Factor Analysis

Cite This Paper in IEEE or APA Citation Styles
(a). IEEE Format:
[1] Hossein Malekinezhad , "Regionalization Approach for Modeling of Monthly Evaporation Based on Cluster Analysis," Natural Resources and Conservation, Vol. 2, No. 2, pp. 25 - 32, 2014. DOI: 10.13189/nrc.2014.020202.

(b). APA Format:
Hossein Malekinezhad (2014). Regionalization Approach for Modeling of Monthly Evaporation Based on Cluster Analysis. Natural Resources and Conservation, 2(2), 25 - 32. DOI: 10.13189/nrc.2014.020202.