On the response of a turbulent coastal buoyant current to wind events: The case of the Western Adriatic Current

Marcello G. Magaldi, Tamay M Ozgokmen, Annalisa Griffa, Michel Rixen

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

This numerical study focuses on the response of the Western Adriatic Current to wind forcing. The turbulent buoyant surface current is induced by the Po river outflow in the Adriatic Sea. Idealized and realistic wind conditions are considered by retaining the complex geomorphology of the middle Adriatic basin. In the absence of wind, the Adriatic Promontories force the current to separate from the coast and induce instabilities. Persistent 7-m s ∈-∈1 downwelling favorable northwesterly winds thicken and narrow the current. Instabilities whose size is ~10 km develop but ultimately vanish, since there is not enough across-shore space to grow. On the contrary, 7-m s∈-∈1 upwelling favorable southeasterly winds thin and widen the current, and instabilities can grow to form mesoscale (~35 km) features. When realistic winds are considered, the same trends are observed, but the state of the sea set up by previous wind events also plays a crucial role. The turbulent regimes set up by different winds affect mixing and the WAC meridional transport. With downwelling winds, the transport is generally southward and mixing happens mostly between the fresher (S≤38) salinity classes. With upwelling winds, the transport decreases and changes sign, and mixing mainly involves saltier (S∈>∈38) waters. In all cases, mixing is enhanced when a finer 0.5-km horizontal resolution is employed.

Original languageEnglish (US)
Pages (from-to)93-122
Number of pages30
JournalOcean Dynamics
Volume60
Issue number1
DOIs
StatePublished - Feb 2010

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coastal current
downwelling
upwelling
wind forcing
geomorphology
outflow
salinity
coast

Keywords

  • Adriatic Sea
  • Cape
  • Gargano Promontory
  • Instabilities
  • Mesoscale variability
  • Mixing
  • Transport
  • Western Adriatic Current

ASJC Scopus subject areas

  • Oceanography

Cite this

On the response of a turbulent coastal buoyant current to wind events : The case of the Western Adriatic Current. / Magaldi, Marcello G.; Ozgokmen, Tamay M; Griffa, Annalisa; Rixen, Michel.

In: Ocean Dynamics, Vol. 60, No. 1, 02.2010, p. 93-122.

Research output: Contribution to journalArticle

Magaldi, Marcello G. ; Ozgokmen, Tamay M ; Griffa, Annalisa ; Rixen, Michel. / On the response of a turbulent coastal buoyant current to wind events : The case of the Western Adriatic Current. In: Ocean Dynamics. 2010 ; Vol. 60, No. 1. pp. 93-122.
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