Constraints on Climate and Habitability for Earth-like Exoplanets Determined from a General Circulation Model

Wolf, Eric T.; Shields, Aomawa L.; Kopparapu, R.; Haqq-Misra, Jacob; Toon, O. B.

doi:10.3847/1538-4357/aa5ffc

Cited by 117 publications

(93 citation statements)

References 64 publications

(144 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Venus may have also been habitable billions of years ago (Abe et al 2011;Cockell 1999;Joseph 2019), and may have remained habitable and able to sustain a variety of life forms until at least 700 million years ago, before it lost its oceans (Way et al 2016) and its atmosphere exceeded the ultimate stage of the "moist greenhouse" effect: Ts ≥ 330 K (Wolf et al 2017). When and what caused this catastrophic alteration in the habitability of Venus is unknown.…”

Section: Habitability and The Heavy Bombardment Phase Of Solar Systemmentioning

confidence: 99%

Seeding the Solar System with Life: Mars, Venus, Earth, Moon, Protoplanets

et al. 2020

View full text Add to dashboard Cite

In the space of the entire universe, the only conclusive evidence of life, is found on Earth. Although the ultimate source of all life is unknown, many investigators believe Earth, Mars, and Venus may have been seeded with life when these planets, and the sun, were forming in a galactic cluster of thousands of stars and protoplanets. Yet others hypothesize that while and after becoming established members of this solar system, these worlds became contaminated with life during the heavy bombardment phase when struck by millions of life-bearing meteors, asteroids, comets and oceans of ice. Because bolide impacts may eject tons of life-bearing debris into space, and as powerful solar winds may blow upper atmospheric organisms into space, these three planets may have repeatedly exchanged living organisms for billions of years. In support of these hypotheses is evidence suggestive of stromatolites, algae, and lichens on Mars, fungi on Mars and Venus, and formations resembling fossilized acritarchs and metazoans on Mars, and fossilized impressions resembling microbial organisms on the lunar surface, and dormant microbes recovered from the interior of a lunar camera. The evidence reviewed in this report supports the interplanetary transfer hypothesis and that Earth may be seeding this solar system with life.

show abstract

Section: Habitability and The Heavy Bombardment Phase Of Solar Systemmentioning

confidence: 99%

Seeding the Solar System with Life: Mars, Venus, Earth, Moon, Protoplanets

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The bistability of Earth-like climates is a well-known feature of EBM's (Caldeira & Kasting, 1992;North et al, 1981) that also appears in many GCMs (DeConto & Pollard, 2003;Ishiwatari et al, 2007;Voigt & Marotzke, 2010;Wolf et al, 2017), with both warm and ice-covered solutions available at a given value of stellar flux. The left panels of Figure 8 illustrate this classic hysteresis loop for 0 • obliquity (top) and 23.5 • obliquity (bottom), with the blue curve representing equilibrium EBM solutions initialized from ice-covered conditions and the red curve indicating solutions initialized from ice cap conditions.…”

Section: Climate Bistabilitymentioning

confidence: 99%

Constraining the Magnitude of Climate Extremes From Time‐Varying Instellation on a Circumbinary Terrestrial Planet

et al. 2019

Self Cite

View full text Add to dashboard Cite

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.

show abstract

“…For exoplanets little is known about seasonal and latitudinal climatologies, however, 3D model calculations have already been used successfully to study Earth-like exoplanets [e.g. [78][79][80][81][82][83]. These advanced models can be used to construct a priori and or initial guess atmospheric state parameters for the retrieval from exoplanet observations.…”

Section: Global Vs Seasonal/latitudinal Atmospheric Datamentioning

confidence: 99%

Transmission spectroscopy with the ACE-FTS infrared spectral atlas of Earth: A model validation and feasibility study

Schreier

Städt

Hedelt

et al. 2018

Molecular Astrophysics

View full text Add to dashboard Cite

Infrared solar occultation measurements are well established for remote sensing of Earth's atmosphere, and the corresponding primary transit spectroscopy has turned out to be valuable for characterization of extrasolar planets. Our objective is an assessment of the detectability of molecular signatures in Earth's transit spectra.To this end, we take a limb sequence of representative cloud-free transmission spectra recorded by the space-borne ACE-FTS Earth observation mission (Hughes et al., ACE infrared spectral atlases of the Earth's atmosphere, JQSRT 2014) and combine these spectra to the effective height of the atmosphere. These data are compared to spectra modeled with an atmospheric radiative transfer line-by-line infrared code to study the impact of individual molecules, spectral resolution, the choice of auxiliary data, and numerical approximations. Moreover, the study serves as a validation of our infrared radiative transfer code.The largest impact is due to water, carbon dioxide, ozone, methane, nitrous oxide, nitrogen, nitric acid, oxygen, and some chlorofluorocarbons (CFC11 and CFC12). The effect of further molecules considered in the modeling is either marginal or absent. The best matching model has a mean residuum of 0.4 km and a maximum difference of 2 km to the measured effective height. For a quantitative estimate of visibility and detectability we consider the maximum change of the residual spectrum, the relative change of the residual norm, the additional transit depth, and signal-to-noise ratios for a JWST setup. In conclusion, our study provides a list of molecules that are relevant for modeling transmission spectra of Earth-like exoplanets and discusses the feasibility of retrieval.

show abstract

Constraints on Climate and Habitability for Earth-like Exoplanets Determined from a General Circulation Model

Cited by 117 publications

References 64 publications

Seeding the Solar System with Life: Mars, Venus, Earth, Moon, Protoplanets

Seeding the Solar System with Life: Mars, Venus, Earth, Moon, Protoplanets

Constraining the Magnitude of Climate Extremes From Time‐Varying Instellation on a Circumbinary Terrestrial Planet

Transmission spectroscopy with the ACE-FTS infrared spectral atlas of Earth: A model validation and feasibility study

Contact Info

Product

Resources

About