Atmospheric Loss and Warming Of The Early Mars
Abstract
Today Mars represents an inhospitable world with a thin 6-mbar atmosphere that cannot support surface water. Current evidence suggests that the early Mars was a wet and at least somewhat warmer world that could support life. How hospitable Mars was for life? The atmospheric evolution of Mars over the last 4 billion years was affected by the rate of atmospheric loss and the chemical changes induced by space weather events from the evolving Sun and the planet's early outgassing history. We apply our atmospheric model enhanced with chemistry that describes photo-collisional dissociation and ionization of molecular nitrogen and carbon dioxide rich atmosphere of the early Mars due to XUV emission and penetration of energetic protons accelerated in extended shock waves driven by super Carrington events from the young Sun. We calculate the rate of atmospheric loss of oxygen ions from the atmosphere of early Mars to be 200 kg/s. This suggests that the early Martian atmosphere was subject to significant erosion, which implies the large rate of outgassing due to tectonic and volcanic activity. We also show that energetic protons produce multiple generations of secondary electrons that contribute to the destruction of N2 into reactive nitrogen, and the subsequent destruction of CO2 and CH4 efficiently producing N2O, a powerful greenhouse gas. The efficient production of nitrous oxide in the Martian troposphere can explain the longstanding problem of the Faint Young Sun paradox for Mars.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.P21C2132A
- Keywords:
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- 6225 Mars;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTSDE: 5405 Atmospheres;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 5419 Hydrology and fluvial processes;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS