Observations of Saharan Dust Intrusions over Potenza, Southern Italy, During 13 Years of Lidar Measurements: Seasonal Variability of Optical Properties and Radiative Impact

Mineral dust is one of the most abundant aerosol components in the atmosphere, accounting for more than half of the total global aerosol burden [1]. In fact, the huge global emission rate [2], the relatively long lifetime (days up to weeks) [3], and the long-range transport capacity [4] produce an accumulation of these particles in the atmosphere. The largest fraction of dust on Earth originates from continuous soil erosion [5]. The African continent, especially its northern part (Sahara Desert), is considered the largest dust source on the Earth, contributing to ∼55% of the total of ∼1536 Tg emitted annually [6]. Convective processes, in combination with strong winds, can transport dust particles over long distances. Specifically, it is possible to distinguish four main trajectory patterns. About 60% of the total dust load from the Sahara Desert remains confined in Africa [7]. About 25% of the dust particles travel across the Atlantic Ocean [8], and only 5% is transported to Asia. The fraction that crosses the Mediterranean area and reaches Europe is approximately 10% [9]. Transport in southern Europe follows typical seasonal patterns [10]. Especially during the warm months, deep convection begins as a result of high surface heating. Consequently, mineral desert dust particles rise to 4–5 km into the free troposphere