An Isopycnic Coordinate Numerical Model of the Agulhas Current with Comparison to Observations
Abstract
Numerical modeling of the Agulhas Current in a limited domain begun by Boudra and Chassignet (1988) is extended. First, five experiments designed to investigate the effects of increased vertical resolution and isopycnal coordinate interface outcropping on the model retroflection and rings are described. Next, two experiments carried out in a more realistically sized basin with more realistic coastal geometry are compared with observations recently collected in the Agulhas region. Five experiments are described to investigate increased vertical resolution and interface outcropping. They proceed from a 3- layer case to a 5-layer case with very thin upper layers. Isopycnal outcropping along the subtropical convergence and around the edge of the Indian Ocean subtropical gyre is a primary feature of three of the new experiments. In addition, some characteristics of ring formation are more realistic than in previously published experiments: e.g., formation is more frequent and is typically west or southwest of the Agulhas Bank as opposed to on the southeast side. The new experiments are generally less energetic. Energy input by the wind is pumped into the lower layers through baroclinic instability and dissipated more efficiently. A three layer experiment and a five layer experiment are run in a larger domain configured on a Mercator projection in order to compare the results to the observations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1990
- Accession Number
- ADA236022
Entities
People
- Kevin A. Maillet
Organizations
- University of Miami