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arXiv · 1611.02572

Geophysical flows under location uncertainty, Part I Random transport and general models

Valentin Resseguier·Etienne Mémin·Bertrand Chapron
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Abstract

A stochastic flow representation is considered with the Eulerian velocity decomposed between a smooth large scale component and a rough small-scale turbulent component. The latter is specified as a random field uncorrelated in time. Subsequently, the material derivative is modified and leads to a stochastic version of the material derivative to include a drift correction , an inhomogeneous and anisotropic diffusion, and a multiplicative noise. As derived, this stochastic transport exhibits a remarkable energy conservation property for any realizations. As demonstrated, this pivotal operator further provides elegant means to derive stochastic formulations of classical representations of geophysical flow dynamics.

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BibTeXRIS

Valentin Resseguier, Etienne Mémin, Bertrand Chapron. 2016-11-03. Geophysical flows under location uncertainty, Part I Random transport and general models. https://doi.org/10.1080/03091929.2017.1310210

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