Effect of spring vegetation indices NDVI & EVI on dust storms occurrence in Iraq

Abstract

The aim of this study is to examine the effects of vegetation indices, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) on dust storms over Iraq in spring season during the period from 2005 to 2014. NDVI and EVI from MODIS sensor and historical dust storms for 11 stations from Iraqi Meteorological Organization and Seismology are used. The results show that the high spring cumulative sum of dust storm frequency is at Karbala and its lower value at Mosul. Dust storms frequency is decrease with increasing vegetation cover where high dust storm years was in 2008 and 2012 tend to face lower spring vegetation indices values, whereas low frequency of dust storm years 2006 and 2014 for almost selected stations are more likely to have high spring EVI and NDVI values. Barren areas (EVI and NDVI <0.1) and poor vegetation cover (EVI and NDVI <0.2) in large areas of Iraq over nearly 60% of Iraq area exist in west and south of Iraq consider one the important factors for the frequent occurrence of dust storms. NDVI shows good negative correlation with dust storms frequency than EVI, conclude that NDVI is suitable than EVI for dust storm study.