Ocean Science Journal

, Volume 48, Issue 2, pp 161–172 | Cite as

Analysis of horizontal and vertical ring structure based on analytical model and satellite data: Application to the North Brazil Current Rings

Article

Abstract

A theoretical analysis of the principal oceanic ring parameters (tangential and angular velocities, shape function, horizontal and vertical scale of the ring) is described. The theoretical model consists of a reduced gravity model of the lens-like vortices with solid body rotation. The application of this approach is tested by comparison with data from the North Brazil Current Rings Experiment and remote sensing data. Specifically, we used the data corresponding to the surfaceintensified North Brazil Current ring (R-3) surveyed in February–March 1999, using direct velocity and hydrographical measurements. The theoretical model was used for evaluating the geometrical structure of the surface-intensified rings that produce remarkable signals in satellite data. The principal ring parameters from the model were compared with those from satellite data (altimetry and drifter information), which were estimated by using the method of minimization of the multivariable objective functions. Although the proposed model is linear in its conception, a good agreement was observed between the model and the primary characteristics of the observed rings. The model, however, allows for improvement in its assumptions, since its application is rather limited to intense ocean rings.

Key words

altimetry drifters ocean ring Brazil Current retroflection 

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Copyright information

© Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Instituto de Astronomía y Meteorología, Departamento de Física, CUCEIUniversidad de GuadalajaraGuadalajaraMéxico
  2. 2.Department of Atmospheric Sciences, Institute of Astronomy, Geosciences and Atmospheric SciencesUniversity of Sao PauloSao PauloBrazil

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