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Original Research Papers

Nonhydrostatic aspects of coastal upwelling meanders and filaments off eastern ocean boundaries

Authors:

Shenn-Yu Chao,

Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland 21613-0775, US
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Ping-Tung Shaw

Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208, US
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Abstract

Coastal upwelling meanders and filaments are common features off eastern ocean boundaries. Their growth is reinvestigated here in using a nonhydrostatic three-dimensional model and a reduced-gravity model, with the objective of assessing contributions from two mechanisms that emerge in the nonhydrostatic regime. The first mechanism is caused by the vertical projection of the Coriolis force in the momentum equation. It is found that the vertical Coriol is force often acts as a restoring force against numerical damping off eastern ocean boundaries and thus enhances the growth of meanders and filaments. The second mechanism arises from unstable ocean stratification when the cold upwelled water intrudes seaward over the warmlayer. The unstable stratification, albeit transient, further enhances the growth of meanders and filaments. It is concluded that although nonhydrostatic effects do not change our understanding of how meanders and filaments grow, the realism can be enhanced using a nonhydrostatic model in so far as meanders and filaments off eastern ocean boundaries are concerned.

How to Cite: Chao, S.-Y. and Shaw, P.-T., 2002. Nonhydrostatic aspects of coastal upwelling meanders and filaments off eastern ocean boundaries. Tellus A: Dynamic Meteorology and Oceanography, 54(1), pp.63–75. DOI: http://doi.org/10.3402/tellusa.v54i1.12120
  Published on 01 Jan 2002
 Accepted on 12 Jun 2001            Submitted on 13 Jun 2000

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