Accession Number:

ADA247635

Title:

The Structure and Transport of the Brazil Current Between 27 deg and 36 deg South

Descriptive Note:

Doctoral thesis,

Corporate Author:

WOODS HOLE OCEANOGRAPHIC INSTITUTION MA

Personal Author(s):

• Zemba, Jan C.

Report Date:

1991-06-01

Pagination or Media Count:

164.0

Abstract:

An analysis of four hydrographic sections from the Thomas Washington marathon cruises--27, 31, 34 and 36 deg S--identifies downstream changes in the Brazil Current. They detail the currents change from a relatively small 12 Sv , near surface feature to a large 80 Sv, deep current. Growth comes from a recirculation cell, deepening shear and a deeper zero velocity surface required if NADW is to flow south. A four layer, basinwide model at 31 deg S ties the size of the Brazil Current and recirculation to various limits on layer-to-layer exchanges south of the section. The resulting flow pattern is consistent with equatorward meridional heat flux in the South Atlantic. Qualitative downstream changes in the total potential vorticity illuminate the presence of both frictional and inertial flow regimes. The presence of a frictional regime at the inshore edge suggests that care should be taken in assuming that potential vorticity is conserved in western boundary currents. The final picture which emerges is not of a small, surface-trapped Brazil Current rather, it is that of a classic western, boundary current, increasing in strength and depth before turning east into the interior ocean.

Descriptors:

• *OCEAN CURRENTS
• *TRANSPORT PROPERTIES
• *OCEANS
• EDGES
• DEPTH
• RECIRCULATION
• BOUNDARIES
• FLOW
• HEAT FLUX
• WATER MASSES
• LAYERS
• MODELS
• VELOCITY
• SURFACES

Subject Categories:

• Physical and Dynamic Oceanography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE