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arXiv · 2011.12112

Point vortices dynamics on a rotating sphere and modeling of global atmospheric vortices interaction

Igor I. Mokhov·Sergey G. Chefranov·Alexander G. Chefranov
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Abstract

It is shown that the hydrodynamics equations for a thin spherical liquid layer are satisfied by the stream function of a pair of antipodal vortices-APV, in contrast to the stream function of a single point vortex on a sphere with a background of a uniform opposite sign vorticity. A simple zero solution of the equation of the absolute vorticity conservation is used for bypassing well-known nonlinear problem of a point vortices interaction with regular vorticity field and an exact solution for APVs dynamics problem on a rotating sphere is obtained. Due to this a new stable stationary solution for the dynamics of APV is obtained, which can model the dynamics of the global vortex structures such as atmospheric centers of action.

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Igor I. Mokhov, Sergey G. Chefranov, Alexander G. Chefranov. 2020-11-12. Point vortices dynamics on a rotating sphere and modeling of global atmospheric vortices interaction. https://doi.org/10.1063/5.0026014

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