Ocean Dynamics

, Volume 65, Issue 8, pp 1095–1102 | Cite as

Influence of the equatorial deep jets on the north equatorial countercurrent

  • Jan-Dirk Matthießen
  • Richard J. Greatbatch
  • Peter Brandt
  • Martin Claus
  • Sven-Helge Didwischus
Article
Part of the following topical collections:
  1. Topical Collection on Atmosphere and Ocean Dynamics: A Scientific Workshop to Celebrate Professor Dr. Richard Greatbatch's 60th Birthday, Liverpool, UK, 10-11 April 2014

Abstract

An ocean circulation model is run using two different idealized equatorial basin configurations under steady wind forcing. Both model versions produce bands of vertically alternating zonal flow at depth, similar to observed Equatorial Deep Jets (EDJs) and with a time scale corresponding to that of the gravest equatorial basin mode for the dominant baroclinic vertical normal mode. Both model runs show evidence for enhanced variability in the surface signature of the North Equatorial Counter Current (NECC) with the same time scale. We also find the same link between the observed NECC and the EDJs in the Atlantic by comparing the signature of the EDJ in moored zonal velocity data at 23° W on the equator with the signature of the NECC in geostrophic velocities from altimeter data. We argue that the presence of a peak in variability in the NECC associated with the EDJ basin mode period is evidence that the influenceatthis time scale is upward, from the EDJ to the NECC.

Keywords

North Equatorial Counter Current Ocean circulation model Equatorial Deep Jets 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Jan-Dirk Matthießen
    • 1
  • Richard J. Greatbatch
    • 1
  • Peter Brandt
    • 1
  • Martin Claus
    • 1
  • Sven-Helge Didwischus
    • 1
  1. 1.GEOMAR Helmholtz Centre for Ocean Research KielKielGermany

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