Variability and coherence of the agulhas undercurrent in a high-resolution ocean general circulation model

A. Biastoch, L. M. Beal, J. R.E. Lutjeharms, T. G.D. Casal

Research output: Contribution to journalArticlepeer-review

37 Scopus citations

Abstract

The Agulhas Current system has been analyzed in a nested high-resolution ocean model and compared to observations. The model shows good performance in the western boundary current structure and the transports off the South African coast. This includes the simulation of the northward-flowing Agulhas Undercurrent. It is demonstrated that fluctuations of the Agulhas Current and Undercurrent around 50-70 days are due to Natal pulses and Mozambique eddies propagating downstream. A sensitivity experiment that excludes those upstream perturbations significantly reduces the variability as well as the mean transport of the undercurrent. Although the model simulates undercurrents in the Mozambique Channel and east of Madagascar, there is no direct connection between those and the Agulhas Undercurrent. Virtual float releases demonstrate that topography is effectively blocking the flow toward the north.

Original languageEnglish (US)
Pages (from-to)2417-2435
Number of pages19
JournalJournal of Physical Oceanography
Volume39
Issue number10
DOIs
StatePublished - Oct 1 2009

ASJC Scopus subject areas

  • Oceanography

Fingerprint Dive into the research topics of 'Variability and coherence of the agulhas undercurrent in a high-resolution ocean general circulation model'. Together they form a unique fingerprint.

Cite this