A Fine Resolution Model of the Leeuwin Current System
Abstract
To investigate the role of wind forcing, bottom topography and thermohaline gradients on classical as well as unique features of the Leeuwin Current system (LCS) five experiments are conducted with a sigma coordinate, primitive equation model on a beta-plane. The first experiment, which investigates the pressure gradient force error, shows that velocity errors, inherent in three dimensional sigma coordinate models, can be successfully reduced from 100 cm/s to 1 cm/s in the LCS. The second experiment, which highlights the effect of annual wind forcing on a flat bottom with horizontally averaged climatology, portrays some classical features of eastern boundary currents such as an equatorward surface current and upwelling. The third experiment uses horizontally averaged climatology and annual winds, but adds realistic topography to investigate its role in the LCS. This results in a different upwelling pattern and a poleward surface current inshore of the main equatorward current. The fourth experiment uses annual temperature and salinity values to investigate the effects of the thermohaline gradient without the annual wind over topography. The addition of the thermohaline gradient drives a strong poleward (equatorward) surface current (undercurrent) . The final experiment attempts to model the LCS using full climatology and annual winds over realistic topography. The results show that despite equatorward winds, the thermohaline gradient continues to force a surface poleward current (equatorward undercurrent).
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2001
- Accession Number
- ADA401599
Entities
People
- Scott Boedeker
Organizations
- Naval Postgraduate School