Interactive comment on “Global trends in visibility: implications for dust sources” by N. M. Mahowald et al

Response to reviewers: The reviewers make excellent suggestions and comments that substantially improve the text. For the most part we modify the text to better reflect their comments. There are a few exceptions, where we do not do as suggested, in which case we explain why we did not. Comments by Reviewer # 1 (Ron Miller) “There seem to be four main conclusions. First, surface extinction, where light attenuation is measured within air at the surface, is a better indicator of local aerosol sources than column optical thickness, where attenuation is measured vertically across the entire column. This is because column extinction includes aerosols high overhead that