HR: 1340h
AN: A43A-0032    [Abstracts]
TI: The Effects of La Nina on the Distribution and Transport of Trace Gases and Aerosols over Southern Africa
AU: * Stein, D C
EM: dcs5v@virginia.edu
AF: University of Virginia, Dept of Environmental Sciences, Clark Hall, PO Box 400123, Charlottesville, VA 22904-4123 United States
AU: Swap, R J
EM: rjs8g@virginia.edu
AF: University of Virginia, Dept of Environmental Sciences, Clark Hall, PO Box 400123, Charlottesville, VA 22904-4123 United States
AU: Macko, S A
EM: sam8f@virginia.edu
AF: University of Virginia, Dept of Environmental Sciences, Clark Hall, PO Box 400123, Charlottesville, VA 22904-4123 United States
AB: At present there is relatively little understanding regarding the behavior of trace gases and aerosols and their resultant long-range transport pathways during high phase El Nino Southern Oscillation (ENSO) years for the region of southern Africa. Atmospheric chemical measurements and atmospheric profiles taken as a part the Southern African Regional Science Initiative (SAFARI 2000) were conducted in the austral winter of 2000 during what was a relatively strong La Nina year. Differences in the frequency of synoptic-scale circulation patterns as a result of changes in Walker Cell positioning led to changes in distribution and transport of trace gases and aerosols for this La Nina year as compared with measurements taken in the region during a previous El Nino year austral winter campaign (SAFARI-92). The climatic mechanisms for these changes and the resultant differences in circulation patterns from the local to synoptic scale are examined through the description of the transport and distribution of aerosols and trace gases. Despite many differences on the synoptic level and climatic level, vertical stability, a key indicator of the nature of the southern African atmosphere, remained relatively the same for both phases of ENSO. The implications of these differences and similarities are examined and explained using the mechanisms of ENSO and Quasi-Biennial Oscillation (QBO) teleconnections and interactions.
DE: 9305 Africa
DE: 3364 Synoptic-scale meteorology
DE: 1620 Climate dynamics (3309)
DE: 0345 Pollution--urban and regional (0305)
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting