Rainfall Data Analysis and Study of Meteorological Draught in Iraq for the Period 1970-2010

Abstract

This work aimed to analyze and evaluate the metrological draught in Iraq. Monthly rainfalldata were collected from 22 meteorological stations scattered all over Iraq for the period 1970-2010. Various statistical tests have been performed to examine the data accuracy, e.g.Consistency test, Trend analysis, as well as homogeneity test. The Standard Precipitation Index(SPI) and Theory of Runs are used to analyze the metrological draught and evaluating thedraught characteristics. SPI values have been estimated for 12-month time scale, from Januaryto December. To analyze the drought characteristics, the accumulative deficit, drought durationand intensity for each station have been estimated. The results showed that the rainfall dataseries considered in the study are all consistent with negative trends except Hilla station, random except Haditha and Samawah stations and homogeneous. It was shown that the study area has been suffered from sequent drought events through nearly half of the years considered in the study, and the worst were in 1997-2001 and 2007-2010 in which extreme droughts were dominated several parts of study area.