HR: 0800h
AN: GC51A-0153    [Abstracts]
TI: The Tropical Atlantic Gradient in Global Climate Models
AU: * Friedman, A R
EM: andfried@atmos.berkeley.edu
AF: Department of Geography, 507 McCone Hall University of California, Berkeley, CA 94720-4740,
AU: Chiang, J
EM: jchiang@atmos.berkeley.edu
AF: Department of Geography, 507 McCone Hall University of California, Berkeley, CA 94720-4740,
AB: The Tropical Atlantic Gradient (TAG), the sea surface temperature difference between the Tropical North Atlantic and Tropical South Atlantic, strongly affects the latitude of the Atlantic Intertropical Convergence Zone, and precipitation in the Caribbean, Northeast Brazil, and West Africa. The TAG appears to have decreased in the second half of the 20th century until increasing in the last two decades, with aerosol forcing and the Atlantic meridional overturning circulation considered the most likely explaining mechanisms. Global climate models (GCMs) do not predict a consistent response in the TAG under climate change scenarios. We investigate the TAG in several GCMs from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project (CMIP) to understand the mechanisms that influence its twentieth-century behavior. We also examine these mechanisms in future climate simulations to better understand why different models project different TAG changes.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1620 Climate dynamics (0429, 3309)
DE: 1626 Global climate models (3337, 4928)
DE: 3337 Global climate models (1626, 4928)
DE: 9325 Atlantic Ocean
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting