Aerosols Optical Properties Over Different Regions Over Iraq

Abstract

investigating the spatial and temporal distribution of aerosols is crucial to the knowledge of their impact on air quality. In present work, the spatiotemporal variation of aerosol over different sites in Iraq was examined using aerosol Optical Depth (AOD) and Angstrom Exponent (AE) from the Moderate Resolution Imaging Spectroradiometer (MODIS) during 2003–2021, and Aerosols Index (AI) retrieved from the Ozone Monitoring Instrument 2005-2021. Satellite retrieval data is divided into three periods include, (2003–2007), (2008–2013) and (2014–2021). The results of the linear regression analysis of aerosol optical properties demonstrate that the second period (monthly mean AOD and AE) has distinct trends in all considered cities when compared with the first and third periods. Between 2008 and 2014, there was a tendency toward increased monthly mean AOD levels whereas monthly mean AE values shows decreasing. The annual mean of AOD is greater than 0.5. This indicates a high aerosol loading with a moderate intensity when equivalent to 0.4. Haditha and Basra experienced the highest annual mean of AOD (lowest AE) during the summer and spring months, while Duhook and Sulaymaniyah had significantly lower values. The results revealed considerable variability of the AOD, AE, and AI monthly mean on both spatial and temporal scales, having the highest AOD, AI, and AE decrease levels in the northwest and southern regions. While there was the lowest AOD, AI, and maximum AE over the northern parts of Iraq. Throughout the study period, the monthly temporal mean of AOD and AI peaked from May to July. These months have the highest aerosol activity, affecting the northwestern, southwest, and southern parts of Iraq. Minimum values of AOD, AI with maximum AE observed in the winter season, having the lowest aerosol activity effect over Iraq.