T. Yamagata et S. Iizuka, SIMULATION OF THE TROPICAL THERMAL DOMES IN THE ATLANTIC - A SEASONALCYCLE, Journal of physical oceanography, 25(9), 1995, pp. 2129-2140
A general ocean circulation model is used to analyze seasonal variatio
ns in the Guinea Dome and Angola Dome regions. The cold Guinea Dome de
velops from June through September due to active divergence of heat tr
ansport. The cooling is related to upwelling generated by the local wi
nd stress curl associated with the northeast trade winds. The Guinea D
ome thus provides an active mechanism of absorbing heat from the atmos
phere. The coastal Guinea region experiences semiannual warming in Apr
il-July and November-December due to intrusion of coastal downwelling
Kelvin waves from the equatorial region. The Angola Dome in the Southe
rn Hemisphere is found to be cooled from March through August. The sur
face flux plays a major role in the seasonal variation of the heat bud
get in contrast to the situation of the Guinea Dome in the Northern He
misphere. The Angola front located at the northern border of the cold
Angola Dome becomes distinguishable particularly during the boreal fal
l because of the intrusion of warm water from the equatorial region. T
he coastal warming occurs twice a year in both hemispheres mostly due
to intrusion of warm water accumulated in the eastern border of the Gu
lf of Guinea. The semiannual relaxation of the trade winds east of 30
degrees W as well as the semiannual intensification of the eastward co
mponent of the West African monsoon is responsible for this remarkable
oceanic phenomenon.