Results from a set of three-dimensional numerical experiments of a hot Jupiter atmosphere

¹ Physics and Astronomy, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, EX4 4QL, UK
e-mail: nathan@astro.ex.ac.uk
² École Normale Supérieure de Lyon, CRAL, UMR CNRS 5574, Université de Lyon, 69364 Lyon Cedex, France
³ Applied Mathematics Group, University of Exeter, Exeter, EX4 4QL, UK
⁴ Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10025, USA
⁵ NASA Goddard Institute for Space Studies, New York, NY 10025, USA
⁶ Department of Computer Science, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF, USA
⁷ Met Office, FitzRoy Road, Exeter, Devon EX1 3PB, UK

Received: 19 January 2017
Accepted: 3 April 2017

Abstract

We present highlights from a large set of simulations of a hot Jupiter atmosphere, nominally based on HD 209458b, aimed at exploring both the evolution of the deep atmosphere, and the acceleration of the zonal flow or jet. We find the occurrence of a super-rotating equatorial jet is robust to changes in various parameters, and over long timescales, even in the absence of strong inner or bottom boundary drag. This jet is diminished in one simulation only, where we strongly force the deep atmosphere equator-to-pole temperature gradient over long timescales. Finally, although the eddy momentum fluxes in our atmosphere show similarities with the proposed mechanism for accelerating jets on tidally-locked planets, the picture appears more complex. We present tentative evidence for a jet driven by a combination of eddy momentum transport and mean flow.