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arXiv · nlin/0102022

Detecting barriers to transport: A review of different techniques

G. Boffetta·G. Lacorata·G. Redaelli·A. Vulpiani
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Abstract

We review and discuss some different techniques for describing local dispersion properties in fluids. A recent Lagrangian diagnostics, based on the Finite Scale Lyapunov Exponent (FSLE), is presented and compared to the Finite Time Lyapunov Exponent (FTLE), and to the Okubo-Weiss (OW) and Hua-Klein (HK) criteria. We show that the OW and HK are a limiting case of the FTLE, and that the FSLE is the most efficient method for detecting the presence of cross-stream barriers. We illustrate our findings by considering two examples of geophysical interest: a kinematic meandering jet model, and Lagrangian tracers advected by stratospheric circulation.

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G. Boffetta, G. Lacorata, G. Redaelli, A. Vulpiani. 2001-02-19. Detecting barriers to transport: A review of different techniques. https://doi.org/10.1016/s0167-2789(01)00330-x

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