HR: 17:00h
AN: A34A-04    [Abstracts]
TI: African Aerosol: An Integral Component of the Tropical Atlantic Climate System?
AU: * Zhang, C
EM: czhang@rsmas.miami.edu
AF: RSMAS, University of Miami, 4600 Rickenbacker Causeway, MPO, Miami, FL 33149
AB: Africa is the largest source of aerosol, including biomass burning aerosol and mineral dust. In the tropical Atlantic, immediately downstream of Africa, the aerosol concentration undergoes seasonal, interannual and decadal variability. Aerosol is known to have climatic impacts through absorption and scattering of radiation and modulation of cloud and precipitation as cloud condensation nuclei and ice nuclei. In the tropical Atlantic, the air-sea coupled climate system also undergoes seasonal, interannual and decadal variability. Tremendous research efforts have been made to understand the climatic impact of aerosol on the one hand, and the dynamics and air-sea coupling of the tropical Atlantic variability on the other hand. There is, however, a striking gap in our knowledge regarding the possible role of African aerosol in the short-term (seasonal, interannual, and decadal) climate variability in the tropical Atlantic. This role is plausible because of the potential effect of African aerosol on cloud and precipitation in the Atlantic marine ITCZ, the coupling between the ITCZ and Atlantic sea surface temperature (SST), influences of Atlantic SST on African rainfall, and connections between African rainfall and African dust. In this presentation, a hypothesis is proposed that African aerosol is an integral component of the climate system in the tropical Atlantic. Knowns and unknowns related to this hypothesis are discussed and possible ways of testing this hypothesis suggested.
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 3374 Tropical meteorology
DE: 3309 Climatology (1620)
DE: 3319 General circulation
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting