HR: 1340h
AN: A43B-0045    [Abstracts]
TI: West African Rainfall and the Tropical Atlantic Ocean: Interactions in the NCEP Coupled System
AU: * Carton, J A
EM: carton@atmos.umd.edu
AF: Department of Meteorology/ESSIC, University of Maryland, College Park, MD 20742 United States
AU: Chang, C
EM: cychang1@umd.edu
AF: Department of Meteorology/ESSIC, University of Maryland, College Park, MD 20742 United States
AU: Grodsky, S
EM: senya@atmos.umd.edu
AF: Department of Meteorology/ESSIC, University of Maryland, College Park, MD 20742 United States
AU: Nigam, S
EM: nigam@atmos.umd.edu
AF: Department of Meteorology/ESSIC, University of Maryland, College Park, MD 20742 United States
AU: Wang, J
EM: jiande.wang@noaa.gov
AF: National Centers for Environmental Prediction/NOAA, 5200 Auth Road, Camp Springs, MD 20746 United States
AB: We present results from an examination of a four member set of 33 year-long integrations using the NCEP atmosphere/ocean coupled general circulation model. Our diagnostic study focuses on the seasonal and interannual fluctations of rainfall over west Africa and the associated changes in winds, heat flux, SST, and ocean heat storage. We begin by presenting the seasonal climatology. We then remove the seasonal cycle from all variables and present an examination of subseasonal variability. The most prominent feature of the subseasonal rainfall variability occurs in the northern tropics and is associated with meridional perturbations of the seasonal ITCZ. Although 1C too warm on average the model's equatorial cold tongue undergoes strong temperature fluctuations from year-to-year. Warm years are associated with enhanced rainfall in the coastal Gulf of Guinea during boreal summer, a feature that appears in the observational record as well. Thus, the model should be a useful tool for understanding the coupled dynamics of west African rainfall and its interaction with the Atlantic cold tongue.
DE: 9305 Africa
DE: 3354 Precipitation (1854)
DE: 3374 Tropical meteorology
DE: 4215 Climate and interannual variability (3309)
DE: 4504 Air/sea interactions (0312)
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting