The Aerosol Effect on Direct Normal Irradiance in a Dust-Rich Hot, Desert Climate
Abstract
This study investigates how the spatial and temporal variations in atmospheric aerosols impact Direct Normal Irradiance (DNI) in a region affected by desert dust intrusions. We employ a three-dimensional atmospheric meteorology-chemistry model (WRF-Chem) with a triple-nesting configuration over the Middle East, focusing particularly on the hot desert climate of the Arabian Peninsula. We analyze data of solar radiation covering five-month periods (May-September), which represent both dry and humid summertime conditions in the region. These data are used to evaluate the model's performance. By implementing an advanced prognostic treatment of aerosols, the model demonstrates significantly improved accuracy in predicting DNI. The influence of aerosols on DNI is particularly pronounced in areas affected by human activities, such as large cities, as well as those experiencing desert dust intrusions. In these regions, aerosol-induced attenuation of DNI can be exceed 70%, corresponding to a reduction of nearly 6 kWh m-2 per day.