HR: 1400h
AN: GC23A-10    [Abstracts]
TI: Variability and Expansion of the Tropical Warm Pool and its effects on Zonal and Meridional Circulation
AU: * Hoyos, C D
EM: choyos@eas.gatech.edu
AF: School of Earth and Atmospheric Sciences Georgia Institute of Technology, 311 Ferst Drive, Atlanta, GA 30332, United States
AU: Webster, P J
EM: pjw@eas.gatech.edu
AF: School of Earth and Atmospheric Sciences Georgia Institute of Technology, 311 Ferst Drive, Atlanta, GA 30332, United States
AB: The tropical warm pool plays a determining role in the global climate since it acts as a sorce of dynamic and thermodynamic forcing for the atmospheric general circulation, providing a source of mositure as well as atmospheric instability resulting in the most convective region in the world. The tropical warm pool is characterized by large-scale variations of SST on time scales that range from intraseasonal to interannual and interdecadal, considerably altering the heat flux exchange with the atmosphere. In addition to existence of the large variability of the tropical warm pool SST, we present evidence of an upward trend in the tropical warm pool area (area of SST > 28°C) , which is evident in the Atlantic, Indian and Pacific oceans. The use of different SST reconstructions, ICOADS data as well as satellite-based SST datasets, confirms the existence of an expanding Tropical Warm Pool. Analysis of several diferent models that are part of the CMIP3 under different emission scnearios, including preindustrial, twentieth century, and one percent increase of CO2 emmissions until doubling, as well as output of the Parallel Climate Model under different forcing scenarios, confirm the results observed in the datasets and suggest that greeenhouse warming plays a determining role in the expansion of the tropical warm pool. Changes in the zonal and meridional circulation associated with the variability and expansion of the warm pool are studied for the last sixty years using NCEP?NCAR and ERA40 reanalsysis. The potential future changes in the atmospheric circulation associated with an expanding tropical warm pool are evaluated using the different CMIP3 scenarios. Preliminary results suggest the existence of important changes in the zonal and meridional circulation in the Atlantic, Pacific and Indian ocean basins in association with the expansion of the tropical warm pool.
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
DE: 3314 Convective processes
DE: 3337 Global climate models (1626, 4928)
DE: 3374 Tropical meteorology
SC: Global Climate Change [GC]
MN: 2007 Joint Assembly