气候变化领域集成服务门户(CCPortal): Timing and magnitude of southern ocean sea ice/carbon cycle feedbacks

CCPortal

DOI	10.1073/pnas.1908670117
	Timing and magnitude of southern ocean sea ice/carbon cycle feedbacks
	Stein K.; Timmermann A.; Kwon E.Y.; Friedrich T.
发表日期	2020
ISSN	0027-8424
起始页码	4498
结束页码	4504
卷号	117 期号:9
英文摘要	The Southern Ocean (SO) played a prominent role in the exchange of carbon between ocean and atmosphere on glacial timescales through its regulation of deep ocean ventilation. Previous studies indicated that SO sea ice could dynamically link several processes of carbon sequestration, but these studies relied on models with simplified ocean and sea ice dynamics or snapshot simulations with general circulation models. Here, we use a transient run of an intermediate complexity climate model, covering the past eight glacial cycles, to investigate the orbital-scale dynamics of deep ocean ventilation changes due to SO sea ice. Cold climates increase sea ice cover, sea ice export, and Antarctic Bottom Water formation, which are accompanied by increased SO upwelling, stronger poleward export of Circumpolar Deep Water, and a reduction of the atmospheric exposure time of surface waters by a factor of 10. Moreover, increased brine formation around Antarctica enhances deep ocean stratification, which could act to decrease vertical mixing by a factor of four compared with the current climate. Sensitivity tests with a steady-state carbon cycle model indicate that the two mechanisms combined can reduce atmospheric carbon by 40 ppm, with ocean stratification acting early within a glacial cycle to amplify the carbon cycle response. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Carbon cycle; Glacial cycles; Sea ice; Southern Ocean
语种	英语
scopus关键词	ice; surface water; air conditioning; Article; atmosphere; biogeochemistry; carbon cycle; cold climate; concentration (parameter); environmental exposure; priority journal; sea ice; simulation; Southern Ocean; steady state
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160312
作者单位	Stein, K., Center for Climate Physics, Institute for Basic Science, Busan, 46241, South Korea, Pusan National University, Busan, 46241, South Korea; Timmermann, A., Center for Climate Physics, Institute for Basic Science, Busan, 46241, South Korea, Pusan National University, Busan, 46241, South Korea; Kwon, E.Y., Center for Climate Physics, Institute for Basic Science, Busan, 46241, South Korea, Pusan National University, Busan, 46241, South Korea; Friedrich, T., Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI 96822, United States
推荐引用方式 GB/T 7714	Stein K.,Timmermann A.,Kwon E.Y.,et al. Timing and magnitude of southern ocean sea ice/carbon cycle feedbacks[J],2020,117(9).
APA	Stein K.,Timmermann A.,Kwon E.Y.,&Friedrich T..(2020).Timing and magnitude of southern ocean sea ice/carbon cycle feedbacks.Proceedings of the National Academy of Sciences of the United States of America,117(9).
MLA	Stein K.,et al."Timing and magnitude of southern ocean sea ice/carbon cycle feedbacks".Proceedings of the National Academy of Sciences of the United States of America 117.9(2020).