Droughts and the Impacts of Dry Spells in North of Iraq

摘要

Different sets of dry spell length such as complete series, monthlymaximum, seasonal maximum, and annual maximum are applied andmodeled with different probability distribution functions (such as GumbelMax, generalized extreme value, Log-Logistic, generalized logistic, inverseGaussian, Log-Pearson 3, generalized Pareto) to recognize in whichduration, dry spells cause drought. The drought situation and temporalanalysis in the North of Iraq region were done using the SPI index andby software of DrinC at a time scale of 3.6 and 12 months. Because ofapplicability, availability of data and the aim of the study, SPI is selectedto analyze the dry spells in this study. Based on the maximum length ofthe available statistical period, the statistics for the years 1980 to 2019were used from nine meteorological stations for analysis. The results of thestudy showed the severity of drought during the study period which relatedto dry spells. The results of this research confirm the variation of droughtoccurrence with varying degrees in different time and different dry spellscondition in Iraq.