Drought Zoning in the Surgical basin in GIS Environment

This paper studies the statistical correlations of 5 meteorological drought indices and the use of monthly rainfall data of 12 climatological and synoptic stations in the Jarrahi and Zohreh basins and surrounding areas. The statistical years were not the same and between 1951 and 2010 these statistics were matched. Drought events were determined using Standard Precipitation Index (SPI), Normal Percentage Index (PNI), Decimal Index (DI), Chinese Z Index (CZI), Z Index (ZSI) and Sequences. Dual correlation coefficients of all stations in this province showed relatively high values, so 54 maps were plotted for 54 years with SPI index and sequences and 1995 and 2010 were the driest years.