Runaway Greenhouse Archives

Detection of the runaway greenhouse threshold. From simulated radius and instellation measurements of a large (N = 500) survey, we compute the moving average (blue confidence intervals) and fit the runaway greenhouse hypothesis to it (Eqn. 4, random draws from the posterior in red). The pattern is detected with high significance. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Imaging & Spectroscopy, Status Report

Bioverse: The Habitable Zone Inner Edge Discontinuity as an Imprint of Runaway Greenhouse Climates on Exoplanet Demographics

by Keith CowingOctober 10, 2023October 9, 2023

Long-term magma ocean phases on rocky exoplanets orbiting closer to their star than the runaway greenhouse threshold – the inner edge of the classical habitable zone – may offer insights […]

Surface temperature as a function of incoming instellation for different hydrogen-helium inventories. The introduction of layers with convective inhibition when the moisture content at the bottom of the atmosphere (BOA) is high enough (orange region) causes a rapid increase in surface temperature (and moisture content). Once the bottom of the atmosphere is pure steam (pink region), the atmosphere becomes optically thick and increasing surface temperature is no longer linked with an increase in cooling, causing a runaway state. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

The Runaway Greenhouse Effect on Hycean Worlds

by Keith CowingApril 11, 2023April 11, 2023

Hycean worlds are a proposed subset of sub-Neptune exoplanets with substantial water inventories, liquid surface oceans and extended hydrogen-dominated atmospheres that could be favourable for habitability.