## 3 Results and Discussion
### Vertical Profiles of DA Effects on SW Radiation, Thermal Structure, and Atmospheric Dynamics
Far from the source areas (i.e., over Italy and the Adriatic Sea), slightly smaller maximum loads (\(\sigma_{\rm ext,dust}\) up to 2.0 \(\times\) 10\({}^{-1}\) km\({}^{-1}\)) are observed within an elevated dust layer near 5 km ASL. On this second day of the DAEC, the SW DDREs are much higher than those on the previous day, becoming maximum (13 W/m\({}^{2}\)) within the elevated dust layers (around 5 km ASL, Figure 6b), while they are smaller (2 to 6 W/m\({}^{2}\)) at lower altitudes along the rest of the cross-section. Above 5 km, the DDREs take very small (almost zero) positive or even negative (at 9 km ASL, from 31.0\({}^{\circ}\) N-10.5\({}^{\circ}\) E to 33.0\({}^{\circ}\) N-20.0\({}^{\circ}\) E) values. The features of the vertically resolved SW heating rates due to DAs (Figure 6c) are identical to those of the corresponding SW DDRE, reaching values up to 0.14 K/3 h around 5 km ASL and down to \(-\)0.001 (atmospheric cooling) around 9 km ASL. As it is shown in Figure 6d, an intense (up to +22 K/km) and spatially extended temperature inversion takes place below and within the surface dust layer, namely off the Tunisian and Libyan coasts (32.5\({}^{\circ}\) N, 11.5\({}^{\circ}\) E) up to the Sicily coasts (36.5\({}^{\circ}\) N, 14.5\({}^{\circ}\) E). Weaker temperature inversions (up to +6 K/km) and reduced temperature gradients (down to \(-\)0.5 K/km) are noted across the rest of the cross-section just below the elevated dust layer (Figure 6d). Again, as already discussed for the first DAEC day, the maximum SW DDREs and heating rates are not found where the maximum DODs exist, namely near the surface above the dust African source areas, but at higher altitudes. This is attributed to the available solar radiation, which gradually decreases with its downward propagation, through the absorbing/scattering dust layer up to about 5 km, but also to the scattering/absorption by other factors such as clouds. Indeed, middle and high clouds (Figure S8i-b), which exist along the slant path of this day (Figure 6e), further reduce the downward SW solar radiation. Finally, on the last day of the DAEC (18 June 2016), the selected slant path runs across the dust export axis, which slightly shifts eastward and covers the Ionian basin and the Aegean Sea (Figure 7e). The dust loadings remain high in this third day of the DAEC, with \(\sigma_{\rm ext,dust}\) values (yellowish and greenish colors) as large as 1.5 \(\times\) 10\({}^{-1}\) km\({}^{-1}\) over the  
Figure 5: Vertical cross-sections of MERRA-2 dust extinction coefficients (in km\({}^{-1}\), (a)), dust solar direct radiative effect in the atmosphere (in W/m\({}^{2}\), (b)), dust solar radiative heating rates (in K/3 h, (c)), and atmospheric temperature gradients (in K/Km, (d)), along the slant path across the African dust export into the Mediterranean Basin (shown on the map of DOD, (e)), during the first day (16 June 2016) of the dust episode that took place during 16–18 June 2016 over the Mediterranean Basin. Libyan dust sources and off the Libyan coasts (from 29.5\({}^{\circ}\) N-11.5\({}^{\circ}\) E to 34.0\({}^{\circ}\) N-15.0\({}^{\circ}\) E), extending from the surface up to 5 km ASL. A distinct elevated dust layer between 3 and 5 km ASL (bluish colors in Figure 7a) is observed over the Ionian basin and Sea (from 34.0\({}^{\circ}\) N-15.0\({}^{\circ}\) E to 40.0\({}^{\circ}\) N-20.0\({}^{\circ}\) E), while a weaker (\(\sigma_{\rm{ext,dust}}\) up to 4.0 \(\times\) 10\({}^{-2}\) km\({}^{-1}\)) elevated dust layer is also observed at similar altitudes over the Balkans (bright orange colors in Figure 7a). Again, as in the previous two days, significant SW DDREs (up to 8 W/m\({}^{2}\), Figure 7b) and heating rates (up to 0.07 K/3 h, Figure 7c) are observed near the dust layer, with the DDREs located a bit higher for the same reasons reported in the previous paragraph, i.e., available solar radiation and significant heating rates down to the surface.