Publication Date



Rainfall pattern, Cluster Analysis, Ward Method, Iran


The identification of spatial rainfall pattern is an essential task for hydrologists, climatologists as well as regional and local planners and managers. This is due to the variability of both the temporal spatial distribution of rainfall. In this study, a hierarchical and divisive cluster analysis was used to categorize these patterns of rainfall in Iran. According to results obtained, there are eight main spatial groups of annual rainfall over Iran. These groups can be classified into 3 main seasonal rainfall regimes namely, winter, winter-spring and fall regimes. The results also show that the elevation and sea neighborhood affect rainfall pattern of Iran. Moreover, a comparison between the Ward and average methods of hierarchical cluster analysis indicates that the Ward method performs the spatial pattern better.