气候变化领域集成服务门户(CCPortal): Implication of strongly increased atmospheric methane concentrations for chemistry-climate connections

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DOI	10.5194/acp-19-7151-2019
	Implication of strongly increased atmospheric methane concentrations for chemistry-climate connections
	Winterstein F.; Tanalski F.; Jöckel P.; Dameris M.; Ponater M.
发表日期	2019
ISSN	16807316
起始页码	7151
结束页码	7163
卷号	19 期号:10
英文摘要	Methane (CH4) is the second-most important directly emitted greenhouse gas, the atmospheric concentration of which is influenced by human activities. In this study, numerical simulations with the chemistry-climate model (CCM) EMAC are performed, aiming to assess possible consequences of significantly enhanced CH4 concentrations in the Earth's atmosphere for the climate. We analyse experiments with 2×CH4 and 5×CH4 presentday (2010) mixing ratio and its quasi-instantaneous chemical impact on the atmosphere. The massive increase in CH4 strongly influences the tropospheric chemistry by reducing the OH abundance and thereby extending the CH4 lifetime as well as the residence time of other chemical substances. The region above the tropopause is impacted by a substantial rise in stratospheric water vapour (SWV). The stratospheric ozone (O3) column increases overall, but SWV-induced stratospheric cooling also leads to a enhanced ozone depletion in the Antarctic lower stratosphere. Regional patterns of ozone change are affected by modification of stratospheric dynamics, i.e. increased tropical upwelling and stronger meridional transport towards the polar regions. We calculate the net radiative impact (RI) of the 2 × CH4 experiment to be 0.69 W m-2, and for the 5 × CH4 experiment to be 1.79 W m-2. A substantial part of the RH is contributed by chemically induced O3 and SWV changes, in line with previous radiative forcing estimates. To our knowledge this is the first numerical study using a CCM with respect to 2- and 5-fold CH4 concentrations and it is therefore an overdue analysis as it emphasizes the impact of possible strong future CH4 emissions on atmospheric chemistry and its feedback on climate. © 2019 Author(s).
语种	英语
scopus关键词	atmospheric chemistry; climate modeling; concentration (composition); methane; ozone depletion; residence time; stratosphere; troposphere; water vapor
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/144372
作者单位	Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany; MERPH-IP Patentanwälte PartG MbB, Munich, Germany
推荐引用方式 GB/T 7714	Winterstein F.,Tanalski F.,Jöckel P.,et al. Implication of strongly increased atmospheric methane concentrations for chemistry-climate connections[J],2019,19(10).
APA	Winterstein F.,Tanalski F.,Jöckel P.,Dameris M.,&Ponater M..(2019).Implication of strongly increased atmospheric methane concentrations for chemistry-climate connections.Atmospheric Chemistry and Physics,19(10).
MLA	Winterstein F.,et al."Implication of strongly increased atmospheric methane concentrations for chemistry-climate connections".Atmospheric Chemistry and Physics 19.10(2019).