Poleward translation of vortices due to deep thermal convection on a rotating planet

Abstract

Atmospheres of gas-giant planets are driven by thermal convection and often exhibit cyclonic circulation at the poles. Here we present the results of the numerical simulations of individual cold and warm blobs in a polar area of a rotating deep spherical layer. The simulations show that the cyclones created at the top of the atmosphere by sinking cold blobs translate northward. The cyclones are the surface signatures of the Taylor columns formed above the descending cold blobs. The Taylor columns are aligned with the planetary axis of rotation and are created by inertial (gyroscopic) waves emitted by the blobs. In contrast, the cyclones created at the bottom of the shell by rising warm blobs move southwards. The numerical results exclude beta-drift from possible reasons of the observed translation.

KEYWORDS:

• Poleward translation
• cyclones
• deep thermal convection
• rotating planet

Acknowledgements

MITgcm is available at http://mitgcm.org/. The data used in figures 2–4 can be found here: https://doi.org/10.6084/m9.figshare.8865149.v1.

Disclosure statement

No potential conflict of interest was reported by authors.

Additional information

Funding

This research was supported by the Natural Sciences and Engineering Research Council of Canada.