9B.3
Initiation of Convective systems in Subsaharan Northern Africa
Mariane Diop, University of Leeds, Leeds, United Kingdom; and D. J. Parker
Understanding of tropical convection remains one of the foremost problems in meteorological prediction and climate study, yet Africa has received less attention in the research community. This study investigates the characteristics of the convective systems in Subsaharan northern Africa for the period 1-9 August 1997, using satellite imagery in conjunction with ECMWF data. Emphasis has been given to the initiation of storms. The relative roles of the orography, the low level synoptic properties and the African easterly waves on the genesis of convective storms have been investigated. Various synoptic measures such as potential instability, wind shear and moisture flux convergence have been linked with the genesis of storms.
It has been found that easterly waves modulate convective initiation most strongly in a zone between 5 W and 7.5 E, where the waves are stronger and topography is generally lower. Elsewhere, the synoptic control appears to be much weaker than the local effects of the diurnal cycle over orography. To the east of the continent, stationary synoptic patterns have been identified.
Session 9B, Large-Scale Dynamics and Convection IV (Parallel with Sessions 9A, 9C, and 9D)
Wednesday, 1 May 2002, 11:00 AM-12:30 PM
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