English

Surface tide on a rapidly rotating body

Solar and Stellar Astrophysics 2019-02-13 v1 Earth and Planetary Astrophysics Fluid Dynamics Geophysics

Abstract

By solving Laplace's tidal equations with friction terms we study the surface tide on a rapidly rotating body. When ϵ=Ω2R/g\epsilon=\Omega^2 R/g, the square of the ratio of dynamical timescale to rotational timescale, is very small for the Earth the asymptotic result was derived. When it is not so small, e.g. a rapidly rotating star or planet, we perform numerical calculations. It is found that when rotation is sufficiently fast (ϵ\epsilon reaches 0.10.1) a great amount of tidal resonances appear. To generate the same level of tide, a faster rotation corresponds to a lower tidal frequency. Friction suppresses tidal resonances but cannot completely suppress them at fast rotation. The thickness of fluid layer can change tidal resonances but this change becomes weaker at faster rotation. This result is of help to understanding the tides in the atmosphere of a rapidly rotating star or planet or in the ocean of a neutron star.

Keywords

Cite

@article{arxiv.1902.00859,
  title  = {Surface tide on a rapidly rotating body},
  author = {Xing Wei},
  journal= {arXiv preprint arXiv:1902.00859},
  year   = {2019}
}
R2 v1 2026-06-23T07:30:38.658Z