Record Details
Field | Value |
---|---|
Title | A comparison of mechanisms generating vertical transport in the Brazilian coastal upwelling regions |
Names |
Mazzini, P. L. F.
(creator) Barth, John A. (creator) |
Date Issued | 2013-11-13 (iso8601) |
Note | This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-9291. |
Abstract | Several mechanisms can drive vertical velocities in the coastal ocean, including wind-forcing and through gradients in the vorticity field generated by flow-topography interactions. A two-layer, steady, wind-driven, analytical model is applied to the major upwelling systems of Brazil : Cabo Frio (CF) and Cabo de Santa Marta (CSM) regions. Comparisons are made between the relative roles of wind and flow-topography interaction in inducing upwelling over these regions. Ekman pumping is the weakest mechanism over the shelf, but does influence the along-shelf temperature in the CF area. Away from coastline irregularities, wind-driven upwelling (Ekman transport) dominates over all mechanisms. However, in the vicinity of capes and coastal features, topographically driven upwelling plays a significant role, and its transports may vary from 43% to 94% of wind-driven upwelling. Upstream of capes, topographically driven vertical motions are downwelling favorable and act against the wind-driven coastal upwelling, while downstream of capes, they are upwelling favorable, where all mechanisms add up to create strong upwelling. Peaks in total upwelling in the CF region are about twice as large as those in the CSM area because the CF region has stronger winds and larger coastline perturbations than in the CSM region. Observed sea surface temperatures (SST) agree well with variability in the vertical transports where upwelling peaks are in phase with low temperature peaks along the coast. Results suggest that on larger scales, the SST variability along the coast is mainly controlled by wind-driven upwelling, while upwelling due to flow-topography interaction is responsible for the smaller scale SST variability. |
Genre | Article |
Topic | Upwelling |
Identifier | Mazzini, P. L. F., and J. A. Barth (2013), A comparison of mechanisms generating vertical transport in the Brazilian coastal upwelling regions, Journal of Geophysical Research: Oceans, 118, 5977–5993. doi:10.1002/2013JC008924 |