Storms, Variability, and Multiple Equilibria on Hot-Jupiters

TL;DR

This paper uses high-resolution simulations to reveal that hot-Jupiter atmospheres contain numerous storms influencing their temperature distribution and variability, with multiple equilibrium states and quasi-periodic storm cycles.

Contribution

It introduces high-resolution pseudospectral simulations that capture small-scale eddies and storms, showing their role in atmospheric variability and multiple equilibrium states.

Findings

Presence of numerous intense storms across scales.

Large storms control temperature distribution and variability.

Atmospheres exhibit multiple equilibrium states with quasi-periodic storm cycles.

Abstract

Observations of hot-Jupiter atmospheres show large variations in the location of the hot spot and the amplitude of spectral features. Atmospheric flow simulations using the commonly-employed forcing and initialization have generally produced a large, monolithic patch of stationary hot area located eastward of the substellar point at $\sim 3\!\times\! 10^{-3}$ MPa pressure level. Here we perform high-resolution (up to T682) pseudospectral simulations that accurately capture small-scale eddies and waves, inherent in hot-Jupiter atmospheres due to ageostrophy. The atmospheres contain a large number of intense storms over a wide range of scales, including the planetary-scale. The latter sized storms dictate the large-scale spatial distribution and temporal variability of hot, as well as cold, regions over the planet. In addition, the large storms exhibit quasi-periodic life cycles within multiple equilibrium states -- all identifiable in the disk-integrated time series of the temperature flux.