Habitable Climates

Abstract

According to the standard liquid-water definition, the Earth is only partially habitable. We reconsider planetary habitability in the framework of energy-balance models, the simplest seasonal models in physical climatology, to assess the spatial and temporal habitability of Earth-like planets. We quantify the degree of climatic habitability of our models with several metrics of fractional habitability. Previous evaluations of habitable zones may have omitted important climatic conditions by focusing on close Solar System analogies. For example, we find that model pseudo-Earths with different rotation rates or different land-ocean fractions have fractional habitabilities that differ significantly from that of the Earth itself. Furthermore, the stability of a planet's climate against albedo-feedback snowball events strongly impacts its habitability. Therefore, issues of climate dynamics may be central in assessing the habitability of discovered terrestrial exoplanets, especially if astronomical forcing conditions are different from the moderate Solar System cases.

Accepted by ApJ. Several references added. 41 pages, 11 figures, 2 tables

References in corpus (17)

• Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits
• Mass-Radius Relationships for Solid Exoplanets
• Discovery of a Cool Planet of 5.5 Earth Masses Through Gravitational Microlensing
• Internal Structure of Massive Terrestrial Planets
• Habitable planets around the star Gl 581?
• Observed Properties of Exoplanets: Masses, Orbits, and Metallicities
• Vegetation's Red Edge: A Possible Spectroscopic Biosignature of Extraterrestrial Plants
• The HARPS search for southern extra-solar planets XI. Super-Earths (5 & 8 M_Earth) in a 3-planet system
• Detailed Models of super-Earths: How well can we infer bulk properties?
• Spectral signatures of photosynthesis II: coevolution with other stars and the atmosphere on extrasolar worlds
• Ocean Planet or Thick Atmosphere: On the Mass-Radius Relationship for Solid Exoplanets with Massive Atmospheres
• Taking the Measure of the Universe: Precision Astrometry with SIM PlanetQuest
• Effects of Orbital Eccentricity on Extrasolar Planet Transit Detection and Lightcurves
• The Response of Atmospheric Chemistry on Earthlike Planets around F, G and K Stars to Small Variations in Orbital Distance
• Characterizing the Orbital Eccentricities of Transiting Extrasolar Planets with Photometric Observations
• Accretion disc outbursts: a new version of an old model
• The habitability of super-Earths in Gliese 581

Cited by in corpus (57)

• Habitable Climates: The Influence of Obliquity
• On the Orbits of Low-mass Companions to White Dwarfs and the Fates of the Known Exoplanets
• Habitable Climates: The Influence of Eccentricity
• Towards the Minimum Inner Edge Distance of the Habitable Zone
• Exomoon habitability constrained by illumination and tidal heating
• Bayesian analysis of the astrobiological implications of life's early emergence on Earth
• Superhabitable Worlds
• Generalized Milankovitch Cycles and Longterm Climatic Habitability
• Magnetospheric Structure and Atmospheric Joule Heating of Habitable Planets Orbiting M-dwarf Stars
• Climate of Earth-like planets with high obliquity and eccentric orbits: implications for habitability conditions
• Habitability of planets on eccentric orbits: the limits of the mean flux approximation
• Candidate Planets in the Habitable Zones of Kepler Stars
• The Hunt for Exomoons with Kepler (HEK): III. The First Search for an Exomoon around a Habitable-Zone Planet
• The extrasolar planet GL 581 d: A potentially habitable planet?
• Climates of Warm Earth-like Planets I: 3-D Model Simulations
• The habitable zone of Earth-like planets with different levels of atmospheric pressure
• Formation, tidal evolution and habitability of the Kepler-186 system
• The Habitable Zone and Extreme Planetary Orbits
• Modeling the surface temperature of Earth-like planets
• Assessing Circumbinary Habitable Zones using Latitudinal Energy Balance Modelling
• Dynamical Effects on the Habitable Zone for Earth-like Exomoons
• Exo-Milankovitch Cycles II: Climates of G-dwarf Planets in Dynamically Hot Systems
• Exo-Milankovitch Cycles I: Orbits and Rotation States
• Milankovitch Cycles of Terrestrial Planets in Binary Star Systems
• Climates of Warm Earth-like Planets II: Rotational 'Goldilocks' Zones for Fractional Habitability and Silicate Weathering
• Habitability and Water Loss Limits on Eccentric Planets Orbiting Main Sequence Stars
• Oscillations in the Habitable Zone around Alpha Centauri B
• On the Spin States of Habitable Zone Exoplanets Around M Dwarfs: The Effect of a Near-Resonant Companion
• The most common habitable planets - atmospheric characterization of the subgroup of fast rotators
• On the probability of habitable planets
• Numerical Testing of The Rare Earth Hypothesis using Monte Carlo Realisation Techniques
• Habitable Snowballs: Temperate Land Conditions, Liquid Water, and Implications for CO${}_2$ Weathering
• The Effect of Planetary Illumination on Climate Modelling of Earthlike Exomoons
• Exomoon Climate Models with the Carbonate-Silicate Cycle and Viscoelastic Tidal Heating
• Quantitative estimates of the surface habitability of Kepler-452b
• From climate models to planetary habitability: temperature constraints for complex life
• Comparative Climates of TRAPPIST-1 planetary system: results from a simple climate-vegetation model
• On the radial velocity detection of additional planets in transiting, slowly rotating M-dwarf systems: the case of GJ 1132
• The Chaotic Nature of TRAPPIST-1 Planetary Spin States
• EOS-ESTM: A flexible climate model for habitable exoplanets
• Relative abundances of CO2, CO, and CH4 in atmospheres of Earth-like lifeless planets
• Climates of Warm Earth-Like Planets III: Fractional Habitability from a Water Cycle Perspective
• Exploring exomoon atmospheres with an idealized general circulation model
• An Energy Balance Model for Rapidly and Synchronously Rotating Terrestrial Planets
• Climate bistability of Earth-like exoplanets
• Effects of a Binary Companion Star on Habitability of Tidally Locked Planets around an M-type Host Star
• The Effect of Seafloor Weathering on Planetary Habitability
• Fundamental Challenges to Remote Sensing of Exo-Earths
• The habitable zone for Earthlike exomoons orbiting Kepler-1625b
• A novel metric for assessing climatological surface habitability
• Rocky planet rotation, thermal tide resonances, and the influence of biological activity
• Extreme Climate Variations from Milankovitch-like Eccentricity Oscillations in Extrasolar Planetary Systems
• The Entropy Principle and the Influence of Sociological Pressures on SETI
• Behaviors of Martian CO2-driven dry climate system and conditions for atmospheric collapses
• Assessing the Climate and Habitability of Tidally Locked Rocky Exoplanets
• Interaction between vegetation and Snowball phases in the late Proterozoic Earth
• New Worlds: Evaluating terrestrial planets as astrophysical objects