Assessment of African desert dust episodes over the southwest Spain at sea level using in situ aerosol optical and microphysical properties

摘要: Desert dust (DD) aerosols reach the El Arenosillo observatory (southwest Spain) following two characteristic pathways at sea level, each showing significant differences in its aerosol microphysical and optical properties. These differences, turn, determine influence on radiative forcing over region. For these events, meteorological scenarios show a depression located North Africa ground level. A Mediterranean pathway occurs when: (1) is Basin or (2) it coupled to high pressure higher latitudes. observed when only Africa. In our inventory, there are clear DD episodes under flow, whereas other specific events take place mixture of African flows. The pure flow associated with increase particle volume scattering coefficient within sub-micron than super-micron size ranges. This result indicates that contribution through processes region for particles D 1 µm. contrast, flows similar effect sub- ranges forcing. range largest impact 0.3 µm