HR: 11:30h
AN: A42B-05 INVITED     [Abstracts]
TI: Tropical Atlantic Variability in the Future
AU: * Hazeleger, W
EM: wilco.hazeleger@knmi.nl
AF: KNMI, PO BOX 201 3730 AE De Bilt The Netherlands, de Bilt, 3730 AE, Netherlands
AB: Tropical Atlantic Variability (TAV) is shaped by atmospheric processes, such as the trade winds and remote patterns of variability, and oceanic processes, such as upwelling on the equator and the transfer of water masses in the upper branch of the meridional overturning circulation (MOC). Climate change affects these processes. In the 21st century the meridional temperature gradients will reduce, the African monsoon will be affected and the MOC is expected to reduce. Abrupt climate change may even occur when the MOC collapses. In this talk the impact of global warming and changes in the MOC on TAV will be discussed. These changes will affect the predictability of the TAV and regional and remote impacts of TAV. For instance, a reduction of the MOC reduces upwelling on the equator and deepens the thermocline, causing a weakening of the thermocline feedback in the eastern cold tongue region. A shift in the Intertropical Convergence Zone will affect thermodynamic feedbacks between the atmosphere and the ocean in the tropics. Results from IPCC-class climate models and a regional coupled ocean-atmosphere model will be used to discuss projections for Tropical Atlantic Variability in the future.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1620 Climate dynamics (0429, 3309)
DE: 1630 Impacts of global change (1225)
DE: 1635 Oceans (1616, 3305, 4215, 4513)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly