HR: 1340h
AN: PP33A-1009    [Abstracts]
TI: Modelling Andes Uplift Impact on Atmospheric Circulation: Consequences for Neogene Faunal and Floral Evolution ?
AU: * Sepulchre, P
EM: pierrese@ucsc.edu
AF: UC Santa Cruz Paleoclimate & Climate Change Research Group, 1156 High Street, Santa Cruz, CA 95064, United States
AU: Sloan, L C
EM: lsloan@es.ucsc.edu
AF: UC Santa Cruz Paleoclimate & Climate Change Research Group, 1156 High Street, Santa Cruz, CA 95064, United States
AU: Fluteau, F
EM: fluteau@ipgp.jussieu.fr
AF: IPG Paris Universite Paris VII, Place de Jussieu, Paris, FRA F75252,
AB: Tectonics in South America is marked by the uplift of the Andes during the Cenozoic. The Andes are approximately 7000 km long, oriented north-south, with some peak elevations in excess of 6000 m. Such a topographic structure has potentially a strong impact on atmospheric circulation. Climate model studies have showed that the Andes, as a topographic barrier, influence eastern Pacific Ocean climate and also meridional moisture transport above the south American continent. However, most studies have been done at the regional scale, and no quantification of rainfall changes due to a lower topography has been done. Here we use the high resolution Atmospheric General Circulation Model LMDz4 to quantify the impact of the Andes topography on the rainfall regime over the whole South American continent. Interpreting sensitivity experiments, we discuss about the tectonics history from 55 Ma to present-day and how to apply this method for Neogene paleoclimate, in a different continental configuration.
DE: 0325 Evolution of the atmosphere (1610, 8125)
DE: 1854 Precipitation (3354)
DE: 3344 Paleoclimatology (0473, 4900)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting