Decadal trends (2009–2018) in Saharan dust transport at Mt. Martano EMEP station, Italy

Saharan dust advections in the Mediterranean Basin are widely studied and subjected to specific regulations due to their impact on the air quality of European cities. As a natural phenomenon, their contribution to PM should be accurately quantified in order to correctly evaluate their impact in anthropized areas. The identification and quantification of Saharan dust advections should be carried out in rural regional background sites. However, there is a lack of suitable sites in Central and Southern Italy, despite its strategic positioning in the Central Mediterranean area. The rural regional background site of Monte Martano site can fill this gap. This study aims at characterising the 10 years climatology of dust at the Monte Martano (MM) site and integrate it in the wider Mediterranean Basin monitoring network. Monte Martano is barely affected by local emissions, with average PM10 concentration of 11.0 ± 7.4 μg m−3, and a marked seasonality compatible with the evolution of the planetary boundary layer (PBL) during the year. Saharan dust advections contribute for 45.9 days per year on average, with a dust load that accounts for 48% of the background PM10 value. The Saharan dust advections' frequency, duration and intensity were evaluated, and a clear seasonality was detected, with minimum probability in summer and long-lasting events mainly occurring in spring and autumn. The dust load calculation was performed with 3 different methods, the EU guideline method, the modified DIAPASON methodology specifically designed for Central Italy and the DREAM8b model. The comparison between the three methods showed a substantial overestimation of the dust load by the model, while the two experimental methods are in accordance (R = 0.97). In conclusion, the MM site has proven to be suitable for Saharan dust monitoring in Central Italy, providing a new insight in the Central Mediterranean Saharan dust observation network.