Calculating the Environmental Drought Index using the De Martonne Equation for the Rainy Months in Iraq

Abstract

Abstract drought is considered one of the most important problems that still facing humanity despite the great scientific progress, arid and semi-arid form about a third of the land area, and no serious effort has been recorded to change this percentage. This study aims to calculate the drought index by using the De Martonne equation and determine the nature of the climate for the rainy months in ten selected meteorological stations in Iraq (Dohuk, Erbil, Sulaymaniyah, Mosul, Baghdad, Rutba, Karbala, Najaf, Nasiriyah, Basra) by using the data of (Temperature, Precipitation) for the period (1980-2022) also, this study aims to show the relationship between the drought index and the amount of precipitation fall and the temperature by calculating the correlation coefficient and to get simple linear regression equations by using sigma plot program. The results showed that the climate change between (extremely-humid, very-humid) during (January, February, and March) and (Mediterranean, semi-arid, very-humid) in (April) And it varies between (arid, semi-arid) in (May, and October) in the northern stations (Dohuk, Mosul, Erbil, Sulaymaniyah), and the climate varies just between (arid, semi-arid) in all rainy months in (Baghdad, Rutba, Karbala, Najaf, Nasiriyah, Basra) stations. The result also showed there was a strong linear correlation between drought index and precipitation Where the correlation coefficient values were recorded between (0.934-0.974), While the correlation coefficient relationship was strong inverse linear correlation where the correlation coefficient values were recorded between ((-0.940) - (-0.996)) in study stations.