Study of Saharan dust outbreak episode over the Po valley (northern Italy) using IDEA-international air quality forecast product

Transport of Saharan (northern Africa) dust above the Mediterranean Sea and Europe is widely studied throughout the literature. A plume of African dust may result in an anomalous increase of Aerosol Optical Depth (AOD), often accompanied by increases in surface Particulate Matter (PM) concentrations over the entire Mediterranean basin, including the Po valley in northern Italy. Therefore, it is important for air quality assessment and forecasting to understand how Saharan dust contributes to the increase of the AOD, since AOD is strongly correlated with an increment of the daily legal limit of particulate matter PM10 (50 μg/m3), set by the European Union on 2008 (2008/50/CE). The present work studies an intense African dust outbreak episode which affected the Po valley in early May, 2013. The approach used in this work includes the use of the International MODIS/AIRS Processing Package (IMAPP) Air Quality Applications software, IDEA-I (Infusing satellite Data into Environmental Applications-International) in order to evaluate the impact of the plume of Sahara dust on the air quality measurements of surface PM10 concentrations over the Po valley domain. The satellite (MODIS Terra/Aqua) observations show the intense outbreak of dust from north of Africa over Italy. They also show significant cloud cover over northern Italy during the outbreak. Even though significant outbreak occurred between the end of April and May 2013, the ground based concentrations do not show significant increases, with values of PM10 remaining within the daily legal limit.