# Habitability of waterworlds: runaway greenhouses, atmospheric expansion, and multiple climate states of pure water atmospheres.

@article{Goldblatt2015HabitabilityOW,
title={Habitability of waterworlds: runaway greenhouses, atmospheric expansion, and multiple climate states of pure water atmospheres.},
author={Colin Goldblatt},
journal={Astrobiology},
year={2015},
volume={15 5},
pages={
362-70
}
}
• C. Goldblatt
• Published 16 March 2015
• Geology, Physics, Environmental Science
• Astrobiology
There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds." I map these as a function of solar constant for planets ranging in size from Mars-sized to 10 Earth-mass. The states are as follows: globally ice covered (Ts ⪅ 245 K), cold and damp (270 ⪅ Ts ⪅ 290 K), hot and moist (350 ⪅ Ts ⪅ 550 K), and very hot and dry (Tsx2A86;900 K). No stable climate exists for 290 ⪅ T s ⪅ 350 K or 550 ⪅ Ts ⪅ 900 K. The union of hot moist and cold damp…

## Figures from this paper

The evolution of habitable climates under the brightening Sun
• Environmental Science, Physics
• 2015
On water‐dominated planets, warming from increased solar insolation is strongly amplified by the water vapor greenhouse feedback. As the Sun brightens due to stellar evolution, Earth will become
Habitability of Exoplanet Waterworlds
• Geology, Physics
The Astrophysical Journal
• 2018
We model the evolution of ocean temperature and chemistry for rocky exoplanets with 10-1000$\times$ Earth's H$_2$O but without H$_2$, taking into account C partitioning, high-pressure ice phases, and
The inhabitance paradox: how habitability and inhabitancy are inseparable
The dominant paradigm in assigning "habitability"' to terrestrial planets is to define a circumstellar habitable zone: the locus of orbital radii in which the planet is neither too hot nor too cold
Hot Hydrogen Climates Near the Inner Edge of the Habitable Zone
• Physics, Environmental Science
The Astrophysical Journal
• 2019
Young terrestrial planets can capture or outgas hydrogen-rich atmospheres with tens to hundreds of bars of H2, which persist for 100 Myrs or longer. Although the earliest habitable conditions on
Atmospheric Evolution on Low-gravity Waterworlds
• Physics, Geology
The Astrophysical Journal
• 2019
Low-gravity waterworlds ($M\lesssim 0.1 M_{\oplus}$) are of interest for their potential habitability. The weakly bound atmospheres of such worlds have proportionally larger radiative surfaces and
The runaway greenhouse radius inflation effect
• Physics, Geology
Astronomy & Astrophysics
• 2019
Planets similar to Earth but slightly more irradiated are expected to enter into a runaway greenhouse state, where all surface water rapidly evaporates, forming an optically thick H2O-dominated
Characteristics of aquatic biospheres on temperate planets around Sun-like stars and M dwarfs
• Physics, Geology
• 2020
It is shown that many salient properties of aquatic biospheres comprising Earth-like biota for habitable rocky planets orbiting Sun-like stars and late-type M-dwarfs are sensitive to the ambient ocean temperature, and eventually decline substantially as the ocean temperature is increased.
What Factors Affect the Duration and Outgassing of the Terrestrial Magma Ocean?
• Geology, Physics
The Astrophysical Journal
• 2019
The magma ocean (MO) is a crucial stage in the build-up of terrestrial planets. Its solidification and the accompanying outgassing of volatiles set the conditions for important processes occurring
Characterisation of the hydrospheres of TRAPPIST-1 planets
• Geology, Physics
• 2021
Planetary mass and radius data are showing a wide variety in densities of low-mass exoplanets. This includes sub-Neptunes, whose low densities can be explained with the presence of a volatile-rich
Atmospheric Convection Plays a Key Role in the Climate of Tidally Locked Terrestrial Exoplanets: Insights from High-resolution Simulations
• Environmental Science, Physics
The Astrophysical Journal
• 2020
Using a 3D general circulation model (GCM), we investigate the sensitivity of the climate of tidally-locked Earth-like exoplanets, Trappist-1e and Proxima Centauri b, to the choice of a convection

## References

SHOWING 1-10 OF 18 REFERENCES
The runaway greenhouse: implications for future climate change, geoengineering and planetary atmospheres
• Physics, Environmental Science
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
• 2012
The good news is that almost all lines of evidence lead us to believe that it is unlikely to be possible, even in principle, to trigger full a runaway greenhouse by addition of non-condensible greenhouse gases such as carbon dioxide to the atmosphere.
Habitable zone limits for dry planets.
• Geology, Physics
Astrobiology
• 2011
It is shown that "land planets" (desert worlds with limited surface water) have wider habitable zones than aqua planets, and it is possible that Venus was a habitable land planet as recently as 1 billion years ago.
Nitrogen-enhanced greenhouse warming on early Earth
• Geology, Environmental Science
• 2009
Early in Earth’s history, the Sun provided less energy to the Earth than it does today. However, the Earth was not permanently glaciated, an apparent contradiction known as the faint young Sun
Evolution of an Impact-Generated H2O–CO2 Atmosphere and Formation of a Hot Proto-Ocean on Earth
• Physics, Environmental Science
• 1988
Abstract Due to impact degassing during accretion, a hot H2O-rich proto-atmosphere was possibly formed on the growing Earth. We investigate the evolution of an impact-generated H2O–CO2 atmosphere at
Effects of high CO2 levels on surface temperature and atmospheric oxidation state of the early Earth
• Environmental Science, Physics
Journal of atmospheric chemistry
• 1984
One-dimensional radiative-convective and photochemical models are used to examine the effects of enhanced CO2 concentrations on the surface temperature of the early Earth and the composition of the
Clouds and the Faint Young Sun Paradox
• Environmental Science
• 2010
Abstract. We investigate the role which clouds could play in resolving the Faint Young Sun Paradox (FYSP). Lower solar luminosity in the past means that less energy was absorbed on Earth (a forcing