Japan Geoscience Union Meeting 2019

Presentation information

[E] Oral

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

[A-OS11] Continental-Oceanic Mutual Interaction: Planetary scale Material Circulation

Wed. May 29, 2019 10:45 AM - 12:15 PM 301A (3F)

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), Takanori Sasaki(Department of Astronomy, Kyoto University), Chairperson:Yosuke Yamashiki(GSAIS Kyoto University), Takanori Sasaki(Department of Astronomy, Kyoto University)

10:45 AM - 11:00 AM

[AOS11-07] The Drivers of early Archean Earth’s Hydrology: Resolving the Faint Young Sun's Paradox

★Invited Papers

*Vladimir Airapetian1, Guillaume Gronoff2, Michael Way3, Meng Jin4 (1.NASA Goddard Space Flight Center/SEEC and American University, 2.NASA LaRC/SSAI, 3.NASA GISS/SEEC, 4.SETI)

Keywords:Earth, Sun, climate, chemistry

Understanding how the early Archean Earth supported standing bodies of liquid surface water under the faint young Sun is one of the greatest challenges of modern science. Can this problem be resolved as a part of the puzzle of understanding of the origin of building blocks of life on early Earth? Here, we present a new concept of how these two pieces of the mystery of life can be reconciled if we reconstruct the eruptive history of space weather from the young Sun at the time when life started on Earth. Our three-dimensional (3D) magnetohydrodynamic model of the young Sun suggests that energetic protons can be accelerated in shock waves driven by frequent and powerful Coronal Mass Ejection events and Corotating Interacting Regions produced by the young Sun's wind. Accelerated protons at energies > 300 MeV penetrated into the nitrogen-rich weakly reducing atmosphere and initiated the reactive chemistry by breaking molecular nitrogen, carbon dioxide, and methane, producing nitrous oxide, the potent greenhouse gas, and hydrogen cyanide, an essential feedstock molecule of life. Our Global Climate Model, ROCKE-3D, suggests that at 4(1000) ppmv of nitrous oxide produced in a 1(0.5) bar atmospheres outputs the mean annualized Earth’s temperature of +16(5.2)C, and thus may provide a resolution of the FYS paradox and explain the presence of early oceans.