The authors have included many of the very good suggestions from the 2 reviewers to come up with a much improved paper that better describes the significance and limitation of their study.

I suggest that you compute the bias and the correlation between simulated AOD and observed AOD in Figure 8 of version 3 of the paper and indicate these two numbers on Figure 8 for future comparisons.

Concerning the reference Shalaby et al., if this paper is now in ACP rather than ACPD, please indicate the correct reference.

In addition to your comments on dust optical properties several authors have pointed out the fact that the OPAC data set overestimates by quite a bit the absorption of dust in the VIS ( see Kaufman et al., 2001; Moulin et al., 2001; Balkanski et al., 2007). It would be worth mentioning.
Miller et al. (2014) have done a fantastic work at characterising the effect of this absorption on TOA forcing, surface temperature and precipitation. You should cite Miller et al., 2014.

How does you RF per unit AOD compare with what Miller et al. (2014) published?

In the caption of Figure 9 please change 'green dotted line' to 'green solid line'.

Which diameter is plotted on panels b and d of Figure 9, is it the MMD?

That's all for this nice paper!

Yves Balkanski

Kaufman, Y. J., Tanr´e, D., Dubovik, D. O., Karnieli, A., and Remer,L. A.: Absorption of sunlight by dust as inferred from satellite and ground-based remote sensing, Geophys. Res. Lett., 28, 1479–1482, 2001.

Moulin, C., Gordon, H. R., Banzon, V. F., and Evans, R. H.: Assessment of Saharan dust absorption in the visible from Sea-WiFS imagery, J. Geophys. Res., 106(D16), 18 239–18 250, doi:10.1029/2000JD900812, 2001.

Balkanski, Y., Schulz, M., Claquin, T., and Guibert, S.: Reevaluation of Mineral aerosol radiative forcings suggests a better agreement with satellite and AERONET data, Atmos. Chem. Phys., 7, 81-95, doi:10.5194/acp-7-81-2007, 2007.

Miller, R.L., P. Knippertz, C. Pérez García-Pando, J.P. Perlwitz, and I. Tegen, (2014) Impact of dust radiative forcing upon climate. In Mineral Dust: A Key Player in the Earth System. P. Knippertz, and J.-B.W. Stuut, Eds. Springer, 327-357, doi:10.1007/978-94-017-8978-3_13, 2014.