Japan Geoscience Union Meeting 2021

Presentation information

[E] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-OS Ocean Sciences & Ocean Environment

[A-OS10] Continental Oceanic Mutual Interaction - Planetary Scale Material Circulationn

Thu. Jun 3, 2021 10:45 AM - 12:15 PM Ch.11 (Zoom Room 11)

convener:Alexandre Yosuke Yamashiki(Earth & Planetary Water Resources Assessment Laboratory Graduate School of Advanced Integrated Studies in Human Survivability Kyoto University), Yukio Masumoto(Graduate School of Science, The University of Tokyo), Takanori Sasaki(Department of Astronomy, Kyoto University), Swadhin Behera(Application Laboratory, JAMSTEC, 3173-25 Showa-machi, Yokohama 236-0001), Chairperson:Yosuke Alexandre Yamashiki(Earth & Planetary Water Resources Assessment Laboratory Graduate School of Advanced Integrated Studies in Human Survivability Kyoto University), Takanori Sasaki(Department of Astronomy, Kyoto University)

11:00 AM - 11:15 AM

[AOS10-08] How do we understand habitable climets on exoplanets?

★Invited Papers

*Takanori Kodama1 (1.Kodama Institute for Science, The University of Tokyo)

Keywords:Exoplanets, Habitable Planets, Climates

A large number of exoplanets have been detected since 1995. Some of these are expected to be rocky planets with Earth-like bulk composition and would have habitable climate. Habitable exoplanets seem to be significant targets for observation of exo-terrestrial planet and exo-life. Most of studies for habitable planets assumed planets with a large amount of water on their surface and estimated the atmospheric structure using the one-dimensional radiative-convective equilibrium model. They introduce the habitable zone, in which planets can maintain liquid water on their surface for a long term. Recently, estimation of the habitable zone with a three-dimensional climate model has begun. They focus on the spatially non-uniform distribution of water vapor in its atmosphere and can discuss climate for terrestrial exoplanets. However, exoplanets should have a wide range of planetary parameter, which includes the amount of water, radius and mass of a planet, atmospheric pressure, orbital parameters, and so on.

We investigate the climate for a planet with a small amount of water on its surface, a land planet. Land planets have less water amount in their atmosphere and can radiate stronger planetary radiation than for aqua planets, which have a large amount of water on their surface. Thus, a planet with a small amount of water on its surface has a wider habitable zone than that for a planet with a large amount of water on its surface [Abe et al., 2011; Kodama et al., 2018; 2019]. Here, we investigate the relationship between the width of the habitable zone and the surface water distribution using 3D GCM(General Circulation Model). We confirm that the habitable zone strongly depends on the surface environment. In this presentation, we summarize the climates and habitability for exo-land planets.

Additionally, in this presentation, I summarize the dependence of planetary parameters for terrestrial exoplanets on their climate.