HR: 1340h
AN: A23A-0886    [Abstracts]
TI: Remote Sensing of Dust Activity and Transport in South America
AU: * Gasso', S
AF: GEST/UMBC/NASA, Goddard Earth Science and Technology Center University of Maryland Baltimore County 5523 Research Park Drive, Suite 320, Baltimore, MD 21228, United States
AB: Most of what it is known about dust activity in the Southern Hemisphere and in particular in South America is based on model simulations and very few dedicated observational studies. The satellite record of dust activity shows a mixed and conflicting picture. For example, the TOMS-Aerosol Index reveals active sources of dust in the argentine and bolivian Altiplano region as well as in central and south Argentina. However, aerosol optical depth record from the MODIS detectors does not show any significant activity and export of dust in the area. This study shows with specific examples that dust production and export from South America is significant. However, dust activity is highly irregular and it is difficult to detect. The MODIS aerosol algorithm tends to fail in detecting dust in the region for a variety of reasons: 1) abundant cloudiness during the dust storm 2) frequent glint conditions over the ocean 3) bright surface over the land. Only a dedicated study that includes algorithm modification suited for retrievals in this area (such as relaxing glint angle and/or cloud masking) and the use of a combination of retrievals from different satellite detectors (MODIS, MISR, CALIOP, OMI) can yield a more realistic picture of dust transport in the Southern South America. As a result, satellite detection of dust transport into the South Atlantic and possibly other high latitude regions is currently being underestimated.
DE: 1029 Composition of aerosols and dust particles
DE: 1030 Geochemical cycles (0330)
DE: 3311 Clouds and aerosols
DE: 4801 Aerosols (0305, 4906)
DE: 4906 Aerosols (0305, 4801)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting