Presentation #629.01 in the session Habitability.
Understanding of volcanic activity on exoplanets is limited. However, the most interesting observational targets are terrestrial exoplanets orbiting close-in to M-dwarf stars, where the “tidal zone”, or region where tidal forcing can be significant, overlaps the traditional habitable zone. These strong exoplanet/M-dwarf tidal interactions may drive significant volcanism, much like Jupiter’s moon Io. To our knowledge, the effect of volcanism on habitable zone planets orbiting M-dwarf stars has never been investigated using a 3-D chemistry-climate-aerosol model (CCAM) and this is currently unknown whether the aerosol cooling would dominate over the greenhouse gas warming. If this is the case, then it may allow the planet to stay habitable at higher insolation than currently estimated by 1-D (Kopparapu et al. 2013) and 3-D climate models (Yang et al. 2013,2014; Kopparapu et al. 2017). In addition to sulfuric aerosols, exo-volcanism can also inject a colossal amount of H2O into the stratosphere, even for planets which do not have liquid water on their surface. We postulate that H2O injected through exo-volcanism could be remotely detectable with JWST. This water vapor can be misinterpreted as tropospheric water evaporated from surface liquid water. It is therefore crucial to understand exo-volcanism, its impact on habitability and the residence time of stratospheric water vapor on tidally locked worlds, so that we may constrain the potential for false positive signals for habitability in future observations. In this presentation, we will show preliminary results on the impact of intense explosive volcanism on the climate and habitability of the TRAPPIST-1 habitable zone planets, potentially highly active worlds, and whether water injected in the planet’s atmosphere through exo-volcanism could be remotely detectable and misinterpreted as a sign of habitable conditions on the surface. These investigation will be carry-on by sequentially connecting a hierarchy of state-of-the-art models, including a volcanic plume model, a 3D climate-chemistry-aerosol model (WACCM), an aerosol microphysics model (CARMA) and a spectral model (PSG).