Atmospheric circulation of hot jupiters: Insensitivity to initial conditions

Beibei Liu, Adam Showman

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

The ongoing characterization of hot Jupiters has motivated a variety of circulation models of their atmospheres. Such models must be integrated starting from an assumed initial state, which is typically taken to be a wind-free, rest state. Here, we investigate the sensitivity of hot-Jupiter atmospheric circulation to initial conditions with shallow-water models and full three-dimensional models. Those models are initialized with zonal jets, and we explore a variety of different initial jet profiles. We demonstrate that, in both classes of models, the final, equilibrated state is independent of initial condition - as long as frictional drag near the bottom of the domain and/or interaction with a specified planetary interior are included so that the atmosphere can adjust angular momentum over time relative to the interior. When such mechanisms are included, otherwise identical models initialized with vastly different initial conditions all converge to the same statistical steady state. In some cases, the models exhibit modest time variability; this variability results in random fluctuations about the statistical steady state, but we emphasize that, even in these cases, the statistical steady state itself does not depend on initial conditions. Although the outcome of hot-Jupiter circulation models depend on details of the radiative forcing and frictional drag, aspects of which remain uncertain, we conclude that the specification of initial conditions is not a source of uncertainty, at least over the parameter range explored in most current models.

Original languageEnglish (US)
Article number42
JournalAstrophysical Journal
Volume770
Issue number1
DOIs
StatePublished - Jun 10 2013

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atmospheric circulation
Jupiter (planet)
Jupiter
sensitivity
drag
atmospheres
radiative forcing
three dimensional models
atmosphere
shallow water
angular momentum
specifications

Keywords

  • hydrodynamics
  • methods: numerical
  • planets and satellites: atmospheres
  • planets and satellites: individual (HD 189733b, HD 209458b)

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Atmospheric circulation of hot jupiters : Insensitivity to initial conditions. / Liu, Beibei; Showman, Adam.

In: Astrophysical Journal, Vol. 770, No. 1, 42, 10.06.2013.

Research output: Contribution to journalArticle

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