HR: 15:45h
AN: A43E-08 [Abstracts]
TI: West African Monsoon in a 20km-Mesh Atmospheric GCM
AU: * Kitoh, A
EM: kitoh@mri-jma.go.jp
AU: Arakawa, O
EM: oarakawa@mri-jma.go.jp
AB:
West African monsoon climate simulated by a global 20-km mesh atmospheric general circulation model
(AGCM) forced by the global sea surface temperature (SST) during the period 1979-2005 is investigated. In
comparison with a lower resolution (180-km mesh) model experiment, it is revealed that the 20-km mesh AGCM
shows the superiority in simulating orographic rainfall not only its location but also its amount. However, both the
models have common biases in northward penetration of summer rainfall into Sahara, which is associated with
moister conditions in the model lower troposphere. This bias is exaggerated in the higher resolution model. The
association of the interannual variability of the West African monsoon rainfall in JJAS season to global SST
distribution, however, is better captured in the 20-km model than that in the 180-km model. Diurnal variation of
precipitation is also compared with the Tropical Rainfall Measuring Mission (TRMM) data.
DE: 3309 Climatology (1616, 1620, 3305, 4215, 8408)
DE: 3337 Global climate models (1626, 4928)
DE: 3354 Precipitation (1854)
DE: 3374 Tropical meteorology
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly