On the Driving Mechanism of the Annual Cycle of the Florida Current Transport

Czeschel, Lars, Eden, Carsten and Greatbatch, Richard John (2012) On the Driving Mechanism of the Annual Cycle of the Florida Current Transport Journal of Physical Oceanography, 42 (5). pp. 824-839. DOI 10.1175/JPO-D-11-0109.1.

[img]
Preview
Text
Czeschel.pdf - Published Version

Download (2898Kb)

Supplementary data:

Abstract

The mechanisms involved in setting the annual cycle of the Florida Current transport are revisited using an adjoint model approach. Adjoint sensitivities of the Florida Current transport to wind stress reproduce a realistic seasonal cycle with an amplitude of ~1.2 Sv (1 Sv ≡ 106 m3 s−1). The annual cycle is predominantly determined by wind stress forcing and related coastal upwelling (downwelling) north of the Florida Strait along the shelf off the North American coast. Fast barotropic waves propagate these anomalies southward and reach the Florida Strait within a month, causing an amplitude of ~1 Sv. Long baroclinic planetary Rossby waves originating from the interior are responsible for an amplitude of ~0.8 Sv but have a different phase. The sensitivities corresponding to the first baroclinic mode propagate westward and are highly influenced by topography. Considerable sensitivities are only found west of the Mid-Atlantic Ridge, with maximum values at the western shelf edge. The second baroclinic mode also has an impact on the Florida Current variability, but only when a mean flow is present. A second-mode wave train propagates southwestward from the ocean bottom on the western side of the Mid-Atlantic Ridge between ~36° and 46°N and at Flemish Cap, where the mean flow interacts with topography, to the surface. Other processes such as baroclinic waves along the shelf and local forcing within the Florida Strait are of minor importance.

Document Type: Article
Keywords: Oceanography; Boundary currents; Ocean dynamics; Waves; oceanic; Ocean models; Seasonal cycle
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-TM Theory and Modeling
OceanRep > The Future Ocean - Cluster of Excellence
Refereed: Yes
DOI etc.: 10.1175/JPO-D-11-0109.1
ISSN: 0022-3670
Projects: Future Ocean
Date Deposited: 29 May 2012 12:26
Last Modified: 25 Oct 2016 07:54
URI: http://eprints.uni-kiel.de/id/eprint/14331

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...