Accession Number:

ADA167091

Title:

Rings of the Agulhas Current,

Descriptive Note:

Corporate Author:

ROSENSTIEL SCHOOL OF MARINE AND ATMOSPHERIC SCIENCE MIAMI FL

Personal Author(s):

Report Date:

1986-01-01

Pagination or Media Count:

21.0

Abstract:

A combination of satellite-tracked surface drifters, satellite- derived sea surface temperature, and ship-measured isotherm depth fields are used to describe two rings formed from the Agulhas Retroflection south of Africa. The drifter and satellite data are used to calculate ring trajectories. The two rings move westward into the South Atlantic. Their trajectories suggest the rings interact with the bottom topography. Ring motion histories are used to remap hydrographic data and estimate the mean radial shape of the ring thermocline. Thermocline topography as defined by the 10 C isotherm depth is then combined with a two-layer diagnostic model to compute the rings momentum and energetics. Results indicate these rings are some of the most energetic in the world. Their large horizontal scales, however, make them less nonlinear than rings associated with the Gulf Stream in terms of a Rossby number criterion. Ring translation appears to be influenced by a complicated combination of self- induced motion. The energy flux and Agulhas ring contributes to the South Atlantic is 7 of the annual wind input over the entire basin. Two rings per year can replace the eddy energy calculated for the basin outside of the direct influence of the Agulhas Retroflection.

Subject Categories:

  • Physical and Dynamic Oceanography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE