Recognition of Precipitation Homogeny Region of in Iran Based on Aphrodite Data Base

It is clear to all that update precipitation data with adequate spatiotemporal resolution is step one for each research on precipitation. To doing this research Iran daily precipitation data with spatial resolution 0.25 degree extracted from Aphrodite data base during 1/1/1951 to 31/12/2007. One time spatial matrix in dimension 20818× 2491 has been created that located days on the rows and pixels on the columns. For each calendar days precipitation long term mean has been calculated and one new matrix in dimension 2491 × 366. By applying cluster analysis with Ward merging method regionalization of precipitation has been done. To detection optimum numbers of clusters, different inter groups variance quality control indices used. Amount of indices for different clusters have been calculated. The results show that regionalization of Iran precipitation into 8 regions is optimum. Amount of precipitation for each months of year in different regions calculated. Disperse of precipitation regions are corresponds with reality. It seems that Aphrodite precipitation data base has adequate accuracy to analysis of spatiotemporal precipitation on Iran.