气候变化领域集成服务门户(CCPortal): Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice

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DOI	10.1038/s41561-019-0466-8
	Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice
	Marzocchi A.; Jansen M.F.
发表日期	2019
ISSN	17520894
卷号	12 期号:12
英文摘要	Palaeo-oceanographic reconstructions indicate that the distribution of global ocean water masses has undergone major glacial–interglacial rearrangements over the past ~2.5 million years. Given that the ocean is the largest carbon reservoir, such circulation changes were probably key in driving the variations in atmospheric CO2 concentrations observed in the ice-core record. However, we still lack a mechanistic understanding of the ocean’s role in regulating CO2 on these timescales. Here, we show that glacial ocean–sea ice numerical simulations with a single-basin general circulation model, forced solely by atmospheric cooling, can predict ocean circulation patterns associated with increased atmospheric carbon sequestration in the deep ocean. Under such conditions, Antarctic bottom water becomes more isolated from the sea surface as a result of two connected factors: reduced air–sea gas exchange under sea ice around Antarctica and weaker mixing with North Atlantic Deep Water due to a shallower interface between southern- and northern-sourced water masses. These physical changes alone are sufficient to explain ~40 ppm atmospheric CO2 drawdown—about half of the glacial–interglacial variation. Our results highlight that atmospheric cooling could have directly caused the reorganization of deep ocean water masses and, thus, glacial CO2 drawdown. This provides an important step towards a consistent picture of glacial climates. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	air-sea interaction; atmosphere-ice-ocean system; carbon sequestration; cooling; glacial environment; glacial-interglacial cycle; global change; North Atlantic Deep Water; paleoceanography; reconstruction; sea ice; water mass; Antarctica
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/124548
作者单位	National Oceanography Centre, Southampton, United Kingdom; Dept. of the Geophysical Sciences, The University of Chicago, Chicago, IL, United States
推荐引用方式 GB/T 7714	Marzocchi A.,Jansen M.F.. Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice[J],2019,12(12).
APA	Marzocchi A.,&Jansen M.F..(2019).Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice.Nature Geoscience,12(12).
MLA	Marzocchi A.,et al."Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice".Nature Geoscience 12.12(2019).