Simulated Phase-dependent Spectra of Terrestrial Aquaplanets in M Dwarf Systems

Abstract

Orbital phase-dependent variations in thermal emission and reflected stellar energy spectra can provide meaningful constraints on the climate states of terrestrial extrasolar planets orbiting M dwarf stars. Spatial distributions of water vapor, clouds, and surface ice are controlled by climate. In turn, water, in each of its thermodynamic phases, imposes significant modulations to thermal and reflected planetary spectra. Here we explore these characteristic spectral signals, based on 3D climate simulations of Earth-sized aquaplanets orbiting M dwarf stars near the habitable zone. By using 3D models, we can self-consistently predict surface temperatures and the location of water vapor, clouds, and surface ice in the climate system. Habitable zone planets in M dwarf systems are expected to be in synchronous rotation with their host star and thus present distinct differences in emitted and reflected energy fluxes depending on the observed hemisphere. Here we illustrate that icy, temperate, and incipient runaway greenhouse climate states exhibit phase-dependent spectral signals that enable their characterization.

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Cited by in corpus (13)

• Persistence of Flare-Driven Atmospheric Chemistry on Rocky Habitable Zone Worlds
• Atmospheric Regimes and Trends on Exoplanets and Brown Dwarfs
• The TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI). Part II: Moist Cases -- The Two Waterworlds
• The TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI). Part III: Simulated Observables -- The return of the spectrum
• Nitrogen Dioxide Pollution as a Signature of Extraterrestrial Technology
• Water Condensation Zones around Main Sequence Stars
• The Effect of Land Fraction and Host Star Spectral Energy Distribution on the Planetary Albedo of Terrestrial Worlds
• Small Sensitivity of the Simulated Climate of Tidally Locked Aquaplanets to Model Resolution
• Phase Modeling of the TRAPPIST-1 Planetary Atmospheres
• Impact of Planetary Parameters on Water Clouds Microphysics
• Fundamental Challenges to Remote Sensing of Exo-Earths
• From Global Climate Models (GCMs) to Exoplanet Spectra with the Global Emission Spectra (GlobES)
• The climates and thermal emission spectra of prime nearby temperate rocky exoplanet targets