Constraining The Magnitude Of Climate Extremes From Time-varying Instellation On A Circumbinary Terrestrial Planet


Circumbinary Terrestrial Planet

Planets that revolve around a binary pair of stars are known as circumbinary planets. The orbital motion of the stars around their center of mass causes a periodic variation in the total instellation incident upon a circumbinary planet.

This study uses both an analytic and numerical energy balance model to calculate the extent to which this effect can drive changes in surface temperature on circumbinary terrestrial planets. We show that the amplitude of the temperature variation is largely constrained by the effective heat capacity, which corresponds to the ocean-to-land ratio on the planet.

Planets with large ocean fractions should experience only modest warming and cooling of only a few degrees, which suggests that habitability cannot be precluded for such circumbinary planets. Planets with large land fractions that experience extreme periodic forcing could be prone to changes in temperature of tens of degrees or more, which could drive more extreme climate changes that inhibit continuously habitable conditions.

Jacob Haqq-Misra, Eric T. Wolf, William F. Welsh, Ravi Kumar Kopparapu, Veselin Kostov, Stephen R. Kane
(Submitted on 13 Nov 2019)
Comments: Accepted for publication in JGR-Planets
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Atmospheric and Oceanic Physics (
Cite as: arXiv:1911.05577 [astro-ph.EP] (or arXiv:1911.05577v1 [astro-ph.EP] for this version)
Submission history
From: Jacob Haqq-Misra
[v1] Wed, 13 Nov 2019 16:17:36 UTC (3,644 KB)

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