## 3 Results and Discussion
### The effect of DA on Buoyancy  
The DA-induced heating rates were used to calculate (Equation (3)) the buoyancy (vertical acceleration, \(\alpha\)) caused by the SW DDRE. The results, namely the cross-sections of computed DA buoyancy, along the selected slant paths during the three days of the examined DAEC (Figures 5e, 6e, and 7e) are shown in Figure 8 (left column). It is found that during the dust episode, the absorption of SW radiation and the consequent radiative heating induce an upward vertical acceleration of air masses, which is directly proportional to the SW heating rates (Figures 5c, 6c and 7c). The strongest buoyance, i.e., largest values of \(\alpha\) (deep red colors), is found close to heights with the highest dust loadings, reaching  
Figure 7: Vertical cross-sections of MERRA-2 dust extinction coefficients (in km\({}^{-1}\), (**a**)), dust solar direct ra-diative 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 third day (18 June 2016) of the dust episode that took place during 16–18 June 2016 over the Mediterranean Basin.  
0.01 m/s\({}^{2}\) at altitudes up to 5-6 km on the second day (17 June 2016, Figure 8i-b), where/ when maximum DDREs and heating rates also occur.  
The importance of the induced vertical acceleration of air parcels by DDREs can be appreciated by comparing their values with the corresponding ones of the prevailing vertical velocities of the air (vertical wind V, right column of Figure 8). Although the magnitude of the DA buoyancy appears to be smaller than the magnitude of V by two to three orders of magnitude, it is not insignificant. Thus, for example, on the first day of the DAEC, the vertical wind speed overall varies from \(-\)25 m/s (downward motions) to 21 m/s (upward motions, Figure 8i-a). On this day, the vertical velocity and the DA-induced acceleration in the elevated dust layer are 9 m/s and 0.002 m/s\({}^{2}\), respectively. This means that should the DA-induced acceleration persist for 1 min, it would increase the vertical velocity by 0.12 m/s or 1.3%, while should it prevail for 10 min, it would result in a vertical wind speed equal to 1.2 m/s, i.e., it would increase it by 33%.  
Dust aerosols either enhance or suppress the convective motions over altitudes having the same (both reddish or bluish) or opposite (reddish-bluish or bluish-reddish) colors. For instance, on the first day of the DAEC, at altitudes up to 1.5 km over 40\({}^{\circ}\) N-9.5\({}^{\circ}\) E, where negative vertical velocity prevails, the dust-induced buoyancy (positive acceleration) acts in the opposite direction, thus suppressing the downward motion of the air. In contrast, above 1.5 km, both DA buoyancy and vertical velocity take positive values and therefore DAs enhance the upward air motion. In order to further assess the strength of the DA buoyancy with respect to the prevailing vertical velocities of the air, the change in the air vertical velocity induced by the DA buoyancy acting for 10 min is computed and is given in Figure S12. It is found that the dust buoyancy along the selected slant paths during the 3 days of the DAEC can cause a change in vertical velocity up to 8.6 m/s, which is of the same order of magnitude and comparable to the prevailing vertical velocities (up to 25.2 m/s, Figure 8). According to the obtained results, the buoyancy induced by DAs during intense dust transport events can partly explain and lead to the generally observed upward motions in and above the dust layers.  
Figure 8: _Cont._