Regionalization and Spatial Analysis of Precipitation of Urmia Lake Basin, Iran

The spatial patterns of precipitation regarding physiography and atmospheric circulations in the Lake Urmia Basin have been investigated. Daily rainfall time series for the 50 most reliable precipitation stations for the period 1980-2010 were analyzed to detect the regional precipitation pattern. To identify rainfall homogeneous regions, principal component analysis was applied to the precipitation dataset. Agglomerative hierarchical clustering analysis using the Ward and Euclidean distance methods revealed three distinctive precipitation regions in the basin influenced by topography and lake. The first region (G1) covers the north and northeastern part of the Lake Urmia. G2 includes stations located in south and southeastern part of the basin, while G3 covers the western part of the lake basin. The results from this study can be used to better plan agricultural land use, cropping patterns and water management in the delineated homogeneous rainfall regions.