TY - JOUR
T1 - H2o2-induced greenhouse warming on oxidized early mars
AU - Ito, Yuichi
AU - Hashimoto, George L.
AU - Takahashi, Yoshiyuki O.
AU - Ishiwatari, Masaki
AU - Kuramoto, Kiyoshi
N1 - Funding Information:
We thank Ramses Ramirez for sharing their albedo spectra and surface temperature data of CO2 atmospheres with us. This work was supported by MEXT/JSPS KAKENHI grant Nos. 17H06457
Funding Information:
2020-04-01 2020-04-28 12:38:48 cgi/release: Article released bin/incoming: New from .zip Chronology of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) 17H06457 Japan Society for the Promotion of Science (JSPS) 18K03719 Japan Society for the Promotion of Science (JSPS) 19H01947 National Institutes of Natural Sciences (NINS) Astrobiology Center Project AB311025 yes
Publisher Copyright:
© 2020. The American Astronomical Society. All rights reserved
PY - 2020/4/20
Y1 - 2020/4/20
N2 - The existence of liquid water within an oxidized environment on early Mars has been inferred by the Mn-rich rocks found during recent explorations on Mars. The oxidized atmosphere implied by the Mn-rich rocks would basically be comprised of CO2 and H2O without any reduced greenhouse gases such as H2 and CH4. So far, however, it has been thought that early Mars could not have been warm enough to sustain water in liquid form without the presence of reduced greenhouse gases. Here, we propose that H2O2 could have been the gas responsible for warming the surface of the oxidized early Mars. Our one-dimensional atmospheric model shows that only 1 ppm of H2O2 is enough to warm the planetary surface because of its strong absorption at far-infrared wavelengths, in which the surface temperature could have reached over 273 K for a CO2 atmosphere with a pressure of 3 bar. A wet and oxidized atmosphere is expected to maintain sufficient quantities of H2O2 gas in its upper atmosphere due to its rapid photochemical production in slow condensation conditions. Our results demonstrate that a warm and wet environment could have been maintained on an oxidized early Mars, thereby suggesting that there may be connections between its ancient atmospheric redox state and possible aqueous environment.
AB - The existence of liquid water within an oxidized environment on early Mars has been inferred by the Mn-rich rocks found during recent explorations on Mars. The oxidized atmosphere implied by the Mn-rich rocks would basically be comprised of CO2 and H2O without any reduced greenhouse gases such as H2 and CH4. So far, however, it has been thought that early Mars could not have been warm enough to sustain water in liquid form without the presence of reduced greenhouse gases. Here, we propose that H2O2 could have been the gas responsible for warming the surface of the oxidized early Mars. Our one-dimensional atmospheric model shows that only 1 ppm of H2O2 is enough to warm the planetary surface because of its strong absorption at far-infrared wavelengths, in which the surface temperature could have reached over 273 K for a CO2 atmosphere with a pressure of 3 bar. A wet and oxidized atmosphere is expected to maintain sufficient quantities of H2O2 gas in its upper atmosphere due to its rapid photochemical production in slow condensation conditions. Our results demonstrate that a warm and wet environment could have been maintained on an oxidized early Mars, thereby suggesting that there may be connections between its ancient atmospheric redox state and possible aqueous environment.
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U2 - 10.3847/1538-4357/ab7db4
DO - 10.3847/1538-4357/ab7db4
M3 - Article
AN - SCOPUS:85085066995
VL - 893
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
M1 - 168
ER -