HR: 0800h
AN: A21B-0440    [Abstracts]
TI: Variability in Vertical Profiles of Water Vapor Associated with African Aerosol over the Tropical Atlantic
AU: * Huang, J
EM: jhuang@rsmas.miami.edu
AF: Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United States
AU: Zhang, C
EM: czhang@rsmas.miami.edu
AF: Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United States
AU: Prospero, J M
EM: jprospero@rsmas.miami.edu
AF: Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United States
AB: We used four years (2003-2006) of MODIS aerosol optical depth and concurrent AIRS profiled water vapor to explore how the vertical distribution of water vapor may systematically change with outbreaks of African aerosol over the tropical Atlantic Ocean. The first step was to look for a relationship in the Barbados region using in-situ Barbados dust record and the profiled relative humidity from meteorological soundings. We extended the study to the synoptic scale in the West Indies using the MODIS and AIRS products. In the tropical Atlantic, preliminary results indicate that water vapor at 850-1000 hPa is significantly less in July on dusty days than clean days over the northeastern tropical Atlantic [5-25N, 30-20W] where African dust is predominant. In contrast, over the southeastern tropical Atlantic [15S-0, 5W-10E], where African biomass burning smoke prevails, water vapor at 600-1000 hPa is significantly higher in August on smoky days than clean days. Additionally, in January when African mixed aerosol (dust and smoke) is anomalously high over the equatorial eastern tropical Atlantic [5S-5N, 15W-5E], less water vapor is observed at two levels: 925-1000 hPa and 500-600 hPa. It is hypothesized that these results are associated with the non-hygroscopic nature of African dust, the hygroscopic properties of African smoke, and their transport pathways over the tropical Atlantic. These results are useful in the design and diagnostics of model simulations of climate effects of aerosols such as aerosol related precipitation change.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0368 Troposphere: constituent transport and chemistry
DE: 0520 Data analysis: algorithms and implementation
DE: 1029 Composition of aerosols and dust particles
DE: 3374 Tropical meteorology
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting