Changes in the African monsoon region at medium-term time horizon using 12 AR4 coupled models under the A1b emissions scenario.

Bernard Fontaine (1) , Pascal Roucou (1) , Paul-Arthur Monerie (1)

1 CRC - Centre de Recherches de Climatologie

This study documents simulated precipitation and circulation changes through the 20C3M and A1b scenario. The portray a robust pattern, associating rainfall deficits in subtropical regions with excesses over West Africa, except in Northern Senegal and Mauritania, with a significant enhancement of both the April-June rainy season in 10/12 models and of the July-September rainy season in 8/12 models. Eastward to 5°W a northward shift in latitude of the moisture flux convergence at 850 hPa is evident in 10/11 models (+0.58 ° in mean) and a southward shift in 6 /11 models in the western region (-0.24°) is observed.

Mots clés: African monsoon; Climate change; Precipitation; West Africa

Domaines: Climatologie; Milieux et Changements globaux

Bernard Fontaine, Pascal Roucou, Paul-Arthur Monerie. Changes in the African monsoon region at medium-term time horizon using 12 AR4 coupled models under the A1b emissions scenario.. Atmospheric Science Letters, 2011, 12 (1), pp.83-88. ⟨10.1002/asl.321⟩. ⟨hal-00463573⟩