Elements of the West African Monsoon Circulation Deduced from METEOSAT Cloud Winds and Simultaneous Aircraft Measurements

Abstract

Cloud winds derived from the European geostationary satellite METEOSAT for the region of the west African monsoon are validated by DC-7 aircraft measurements for the low levels of the tropical atmosphere. Since the two sets of results are in agreement, it appears that lowest level cumuli as well as stratocumuli can be used as tracers of the actual wind field. The satellite wind fields show a large-scale circulation characterized by two opposite flows in the lower layers: the southwesterly monsoon flow near the sea surface and a northeasterly flow above, at approximately the 2000 m level.