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Center of mass estimation in closed vortices - A verification in principle and practiceThe problem of tracking closed mesoscale vortices using center of mass estimation techniques is studied. Three estimators are evaluated using data from a warm core Gulf Stream ring. The comparisons show that a method based on the intersection of perpendicular bisectors and one using a least-squares fit of a conic section perform comparably. The perpendicular bisector algorithm is used in conjunction with a Gaussian ring model and a star-shaped survey pattern to produce an expected error curve as a function of vortex translation, survey speed and vortex size. For typical ring parameters, center estimation is usually possible to within + or - 5 km. The feasibility of using differing data sets to construct a history of ring motion based on a coordinate system moving with the ring is also investigated. In this way, the validity of using satellite-derived data and drifter trajectories to estimate the center of mass of a mesoscale feature is assessed. The results of the analysis demonstrate that the location of the deeper structure of the ring and the surface expression are sufficiently well correlated to permit dynamically relevant calculations based on surface measurements. It is shown that satellite-derived data can be used to approximate the center of mass trajectory to within the error in the individual center estimates for the period analyzed. The Lagrangian-drifter-derived centers are offset from the center of mass trajectory in a manner consistent with kinematic arguments.
Document ID
19850037266
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Hooker, S. B.
(Miami Univ. FL, United States)
Olson, D. B.
(Miami, University Miami, FL, United States)
Date Acquired
August 12, 2013
Publication Date
September 1, 1984
Publication Information
Publication: Journal of Atmospheric and Oceanic Technology
Volume: 1
ISSN: 0739-0572
Subject Category
Oceanography
Accession Number
85A19417
Funding Number(s)
CONTRACT_GRANT: NAGW-273
CONTRACT_GRANT: N00014-80-C-0042
CONTRACT_GRANT: NSF OCE-80-16991
CONTRACT_GRANT: NSF OCE-80-18736
Distribution Limits
Public
Copyright
Other

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