气候变化领域集成服务门户(CCPortal): A nitrogen-rich atmosphere on ancient Mars consistent with isotopic evolution models

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DOI	10.1038/s41561-021-00886-y
	A nitrogen-rich atmosphere on ancient Mars consistent with isotopic evolution models
	Hu, Renyu; Thomas, Trent B.
发表日期	2022
ISSN	1752-0894
EISSN	1752-0908
起始页码	106
结束页码	+
卷号	15 期号:2 页码:15
英文摘要	The isotopic composition of nitrogen in the Martian atmosphere can be explained by a nitrogen-rich ancient atmosphere, according to models of atmospheric evolution. The ratio of nitrogen isotopes in the Martian atmosphere is a key constraint on the planet's atmospheric evolution. However, enrichment of the heavy isotope expected due to atmospheric loss from sputtering and photochemical processes is greater than measurements. A massive, multi-bar early CO2-dominated atmosphere and recent volcanic outgassing have been proposed to explain this discrepancy, and many previous models have assumed atmospheric nitrogen rapidly reached a steady state where loss to space balanced volcanic outgassing. Here we show using time-dependent models that the abundance and isotopic composition of nitrogen in the Martian atmosphere can be explained by a family of evolutionary scenarios in which the initial partial pressure of nitrogen is sufficiently high that a steady state is not reached and nitrogen levels gradually decline to present-day values over 4 billion years. Our solutions do not require a multi-bar early CO2 atmosphere and are consistent with volcanic outgassing indicated by both geologic mapping and the atmospheric Ar-36/Ar-38 ratio. Monte Carlo simulations that include these scenarios estimate that the partial pressure of N-2 was 60-740 mbar (90% confidence, with a median value of 310 mbar) at 3.8 billion years ago when the valley networks formed. We suggest that such a high nitrogen partial pressure could have contributed substantially to warming on early Mars.
学科领域	Geosciences, Multidisciplinary
语种	英语
WOS研究方向	Geology
WOS记录号	WOS:000753959100005
来源期刊	NATURE GEOSCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/272588
作者单位	California Institute of Technology; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); California Institute of Technology; University of Washington; University of Washington Seattle
推荐引用方式 GB/T 7714	Hu, Renyu,Thomas, Trent B.. A nitrogen-rich atmosphere on ancient Mars consistent with isotopic evolution models[J],2022,15(2):15.
APA	Hu, Renyu,&Thomas, Trent B..(2022).A nitrogen-rich atmosphere on ancient Mars consistent with isotopic evolution models.NATURE GEOSCIENCE,15(2),15.
MLA	Hu, Renyu,et al."A nitrogen-rich atmosphere on ancient Mars consistent with isotopic evolution models".NATURE GEOSCIENCE 15.2(2022):15.