Evaluation of Meteorological Drought Index for Drought Assessment and Mapping in Lorestan Province in Iran

Abstract

Droughts are major natural disasters for many parts of the world. Dry areas where the precipitation pattern is markedly seasonal, or is otherwise highly variable, are the most susceptible. The Iranian Prairies are often subjected to drought, and it is sometimes catastrophic Therefore, understanding the drought conditions through the prediction and zoning of drought extents can considerably decrease the damaging risks of this phenomenon. This research has been done with statistical correlations of 5 meteorological drought indicators and monthly rainfall data of 15 synoptic and climatological stations in Lorestan province and its surrounding. Statistical years weren't the same and the statistical period is between 1951 to 2010 years. Drought events are determined with the use of indicators such as: Standardized Precipitation Indicator (SPI), Percentage of Normal Indicator (PNI), Deciles of precipitation Index (DI), Chinese Indicator (CZI), Z-scores Standardized Indicator (ZSI) and sequences. Dual correlation coefficients in all stations of this province showed relatively high values, According to indicators as (SPI, PNI, DI) the driest years were: 1964, 1966, 1973, 1990, 2008 and 2010.