Does dust from Patagonia reach the sub-Antarctic Atlantic Ocean?

Abstract

Although emission of dust from the Patagonia desert is shown by global aerosol models, there is conflicting observational evidence of dust activity in the region. Because dust from Patagonia into the Southern Ocean (SO) may play a role in regulating phytoplankton activity, it is necessary to confirm whether there is dust activity and if so, how far the dust travels into the SO. We used a combination of surface visibility, satellite measurements (MODIS and OMI) and transport model (HYSPLIT) to track and report for the first time a dust event originating in Patagonia. We show that the dust reached the free troposphere in the Sub-Antarctic Atlantic Ocean. Although the dust emission was significant, cloudiness and dilution of the plume resulted in difficult conditions to track dust in the SW Atlantic. We show that the use of any single tool (i.e., MODIS or OMI) is not enough to track the dust and only an integrated approach of satellite and modeling tools can achieve a consistent description. As a result, current platforms used for dust detection are probably underestimating aerosol loading in the area. Copyright 2007 by the American Geophysical Union.