Dynamics of an Equatorial River Plume: Theory and Numerical Experiments Applied to the Congo Plume Case

Type Article
Date 2014-03
Language English
Author(s) Vic Clement3, Berger Henrick2, Treguier Anne-Marie4, Couvelard Xavier1, 3
Affiliation(s) 1 : UBO IFREMER CNRS IRD, UMR6523, Lab Phys Oceans, Brest, France.
2 : Actimar, Brest, France.
Source Journal Of Physical Oceanography (0022-3670) (Amer Meteorological Soc), 2014-03 , Vol. 44 , N. 3 , P. 980-994
DOI 10.1175/JPO-D-13-0132.1
WOS© Times Cited 10
Keyword(s) Geographic location, entity, Rivers, Circulation, Dynamics, Coastal flows, Density currents, Eddies, Nonlinear dynamics, Topographic effects
Abstract The Congo River has the second largest rate of flow in the world and is mainly responsible for the broad tongue of low-salinity water that is observed in the Gulf of Guinea. Despite their importance, near-equatorial river plumes have not been studied as thoroughly as midlatitude plumes and their dynamics remain unclear. Using both theory and idealized numerical experiments that reproduce the major characteristics of the region, the authors have investigated the dynamics of the Congo River plume and examine its sensitivity to different forcing mechanisms. It is found that near-equatorial plumes are more likely to be surface trapped than midlatitude plumes, and the importance of the effect in describing the strong offshore extent of the low-salinity tongue during most of the year is demonstrated. It is shown that the buoyant plume constrained by the geomorphology is subject to the pulling of nonlinear structures and wavelike equatorial dynamics. The wind is found to strengthen the intrinsic buoyancy-driven dynamics and impede the development of the coastal southward current, in coherence with observations.
Full Text
File Pages Size Access
Publisher's official version 15 2 MB Open access
Top of the page