Free Content On the generation of North Brazil Current rings

 Download
(PDF)
 
Download Article:

Abstract:

A high resolution general circulation model (OGCM) is used to investigate the life cycle of North Brazil Current (NBC) rings. The focus of the study is on explaining the generation mechanisms of the rings and their vertical structure. The OGCM is used in a configuration simplified as much as possible but capable of reproducing a realistic mean circulation of the tropical Atlantic.

Three numerical experiments are analyzed: no wind; steady wind; seasonally varying winds. With wind forcing, a consistent scenario emerges for the generation of NBC rings. It is shown first that the NECC is barotropically unstable, radiating Rossby waves of the first baroclinic mode with a period of 63 days (steady wind) or 50 days (variable wind). These waves reflect at the Brazilian coast and create about 6 -7 anticyclones per year. These anticyclones intensify as they propagate northwestward along the Brazilian coast because of potential vorticity conservation and become NBC rings. Among them, about one per year reaches a depth below 1000 m. These deep rings are created by the merger of a surface NBC ring with an intermediate eddy. The intermediate eddies are produced by the Intermediate Western Boundary Current (IWBC) which becomes unstable upon crossing the equator.

Document Type: Research Article

DOI: http://dx.doi.org/10.1357/002224003322005050

Publication date: March 1, 2003

More about this publication?
  • The Journal of Marine Research publishes peer-reviewed research articles covering a broad array of topics in physical, biological and chemical oceanography. Articles that deal with processes, as well as those that report significant observations, are welcome. In the area of biology, studies involving coupling between ecological and physical processes are preferred over those that report systematics. Authors benefit from thorough reviews of their manuscripts, where an attempt is made to maximize clarity. The time between submission and publication is kept to a minimum; there is no page charge.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more