气候变化领域集成服务门户(CCPortal): Transient Response of Southern Ocean Ecosystems During Heinrich Stadials

CCPortal

DOI	10.1029/2023PA004754
	Transient Response of Southern Ocean Ecosystems During Heinrich Stadials
	Saini, Himadri; Meissner, Katrin J.; Menviel, Laurie; Kvale, Karin
发表日期	2024
ISSN	2572-4517
EISSN	2572-4525
起始页码	39
结束页码	2
卷号	39 期号:2
英文摘要	Antarctic ice core records suggest that atmospheric CO2 increased by 15-20 ppm during Heinrich stadials (HS). These periods of abrupt CO2 increase are associated with a significant weakening of the Atlantic meridional overturning circulation (AMOC), and a warming at high southern latitudes. As such, modeling studies have explored the link between changes in AMOC, high southern latitude climate and atmospheric CO2. While proxy records suggest that the aeolian iron input to the Southern Ocean decreased significantly during HS, the potential impact on CO2 of reduced iron input combined with oceanic circulation changes has not been studied in detail. Here, we quantify the respective and combined impacts of reduced iron fertilization and AMOC weakening on CO2 by performing numerical experiments with an Earth system model under boundary conditions representing 40,000 years before present (ka). Our study indicates that reduced iron input can contribute up to 6 ppm increase in CO2 during an idealized Heinrich stadial. This is caused by a 5% reduction in nutrient utilization in the Southern Ocean, leading to reduced export production and increased carbon outgassing from the Southern Ocean. An AMOC weakening under 40ka conditions and without changes in surface winds leads to a similar to 0.5 ppm CO2 increase. The combined impact of AMOC shutdown and weakened iron fertilization is almost linear, leading to a total CO2 increase of 7 ppm. Therefore, this study highlights the need of including changes in aeolian iron input when studying the processes leading to changes in atmospheric CO2 concentration during HS. Simulated marine ecosystems and CO2 respond linearly to the combined impact of freshwater addition and reduced iron flux into the ocean A maximum of 7 ppm increase in CO2 is simulated due to the AMOC shutdown and weakened iron fertilization under MIS 3 boundary conditions Reduced aeolian iron flux in the Southern Ocean during Heinrich Stadials can lead up to 6 ppm rise in CO2
英文关键词	Heinrich stadial; iron fertilization; marine ecosystems; carbon cycle; AMOC shutdown
语种	英语
WOS研究方向	Geology ; Oceanography ; Paleontology
WOS类目	Geosciences, Multidisciplinary ; Oceanography ; Paleontology
WOS记录号	WOS:001169303900001
来源期刊	PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/304484
作者单位	University of New South Wales Sydney; University of Tasmania; GNS Science - New Zealand
推荐引用方式 GB/T 7714	Saini, Himadri,Meissner, Katrin J.,Menviel, Laurie,et al. Transient Response of Southern Ocean Ecosystems During Heinrich Stadials[J],2024,39(2).
APA	Saini, Himadri,Meissner, Katrin J.,Menviel, Laurie,&Kvale, Karin.(2024).Transient Response of Southern Ocean Ecosystems During Heinrich Stadials.PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY,39(2).
MLA	Saini, Himadri,et al."Transient Response of Southern Ocean Ecosystems During Heinrich Stadials".PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY 39.2(2024).