Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

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

[A-OS12] Continental-Oceanic Mutual Interaction: Planetary scale Material Circulation

Tue. May 22, 2018 10:45 AM - 12:15 PM 106 (1F International Conference Hall, Makuhari Messe)

convener:Yosuke Alexandre 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), Swadhin Behera(Climate Variation Predictability and Applicability Research Group, Application Laboratory, JAMSTEC, 3173-25 Showa-machi, Yokohama 236-0001, 共同), Takanori Sasaki(Department of Astronomy, Kyoto University), Chairperson:Masumoto Yukio, Sasaki Takanori(Department of Astronomy, Kyoto University)

11:15 AM - 11:30 AM

[AOS12-09] Habitability of ice-covered ocean planets with high-pressure ices

*Takanori Sasaki1, Shoji Ueta2 (1.Department of Astronomy, Kyoto University, 2.Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University)

Keywords:exoplanet, habitability, ocean, ice

Since the first discovery in 1995, over 3,700 exoplanets have been identified so far. Some of them are known to be located in the habitable zones around the central stars. Planets with plentiful water on the surface but outside the outer edge of the habitable zone would be globally covered with ice and no liquid water would exist on the surface. However, these “snowball planets” would have liquid water beneath the surface ice shell if sufficient geothermal heat flows up from the planetary interior to melt the interior ice. We discuss the conditions that must be satisfied for ice-covered ocean planets to have an internal ocean on the timescale of planetary evolution. We also investigate the structures of surface H2O layers of snowball planets by considering the effects of high-pressure ices. We found high-pressure ice layers underlying the internal ocean are likely to affect the habitability of the planet.