Investigating the connection between complexity of isolated trajectories and Lagrangian coherent structures
Rypina, Irina I.
Scott, S. E.
Pratt, Lawrence J.
Brown, Michael G.
MetadataShow full item record
It is argued that the complexity of fluid particle trajectories provides the basis for a new method, referred to as the Complexity Method (CM), for estimation of Lagrangian coherent structures in aperiodic flows that are measured over finite time intervals. The basic principles of the CM are explained and the CM is tested in a variety of examples, both idealized and realistic, and in different reference frames. Two measures of complexity are explored in detail: the correlation dimension of trajectory, and a new measure – the ergodicity defect. Both measures yield structures that strongly resemble Lagrangian coherent structures in all of the examples considered. Since the CM uses properties of individual trajectories, and not separation rates between closely spaced trajectories, it may have advantages for the analysis of ocean float and drifter data sets in which trajectories are typically widely and non-uniformly spaced.
© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution 3.0 License. The definitive version was published in Nonlinear Processes in Geophysics 18 (2011): 977-987, doi:10.5194/npg-18-977-2011.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Helfrich, Karl R.; White, Brian L. (Copernicus Publications on behalf of the European Geosciences Union and the American Geophysical Union, 2010-07-15)Large-amplitude internal solitary waves in continuously stratified systems can be found by solution of the Dubreil-Jacotin-Long (DJL) equation. For finite ambient density gradients at the surface (bottom) for waves of ...
Smith, Keston W.; Aretxabaleta, Alfredo L. (Copernicus Publications on behalf of the European Geosciences Union and the American Geophysical Union, 2007-02-01)Expectation maximization (EM) is used to estimate the parameters of a Gaussian Mixture Model for spatial time series data. The method is presented as an alternative and complement to Empirical Orthogonal Function (EOF) ...
Grimshaw, Roger H. J.; Helfrich, Karl R.; Scotti, Alberto (Copernicus Publications on behalf of the European Geosciences Union and the American Geophysical Union, 2011-10-07)The flow in the coastal ocean, and especially on the continental shelf and slope is often characterized by the presence of very large-amplitude internal waves. These are waves which occur in the interior of the ocean, ...