气候变化领域集成服务门户(CCPortal): A 250-Year, Decadally Resolved, Radiocarbon Time History in the Gulf of Maine Reveals a Hydrographic Regime Shift at the End of the Little Ice Age

CCPortal

DOI	10.1029/2020JC016579
	A 250-Year, Decadally Resolved, Radiocarbon Time History in the Gulf of Maine Reveals a Hydrographic Regime Shift at the End of the Little Ice Age
	Lower-Spies E.E.; Whitney N.M.; Wanamaker A.D.; Griffin S.M.; Introne D.S.; Kreutz K.J.
发表日期	2020
ISSN	21699275
卷号	125 期号:9
英文摘要	In order to document relative changes in water mass contributions in the Gulf of Maine (GoM), we used the shell material of the long-lived ocean quahog (Arctica islandica). A multicentury, crossdated master shell growth chronology facilitated the reconstruction of a radiocarbon Δ14C history prior to the radiocarbon bomb-pulse of the 1950s. This reconstruction reveals a highly variable Δ14C series (mean = −56.6 ± 8.0‰ (1σ); N = 34) from CE 1685 to 1935. Δ14C values indicate a rapid shift ca. 1860 CE in source waters to the GoM. From CE 1685 to 1860, GoM waters were dominated by an admixture of Warm Slope Water primarily composed of tropical Atlantic surface waters/Gulf Stream Waters, and Scotian Shelf Water. This water regime was followed by a rapid Δ14C transition to a Labrador Slope Water endmember after CE 1860, with an apparent decrease in Scotian Shelf Water. Together, this shift is likely related to broader changes in the Arctic and the Labrador Sea, and a short-term strengthening of the Atlantic meridional overturning circulation. Labrador Slope Water dominating GoM hydrography in the 1900s is verified by the similarities between this record and other coral- and shell-derived Δ14C records influenced by waters with Labrador Sea origin. This suggests that GoM radiocarbon variability broadly reflects large-scale ocean circulation processes in the Northwestern Atlantic. The lack of Δ14C values much below the Labrador Slope Water endmember suggests that the interior GoM gets very little to no Antarctic Intermediate Water as other studies had previously suggested. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Gulf of Maine; Little Ice Age; ocean circulation; proxy; radiocarbon; water masses
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186676
作者单位	Department of Geological and Atmospheric Sciences, Iowa State University, IA, United States; School of Earth and Climate Sciences and the Climate Change Institute, University of Maine, Orono, ME, United States
推荐引用方式 GB/T 7714	Lower-Spies E.E.,Whitney N.M.,Wanamaker A.D.,et al. A 250-Year, Decadally Resolved, Radiocarbon Time History in the Gulf of Maine Reveals a Hydrographic Regime Shift at the End of the Little Ice Age[J],2020,125(9).
APA	Lower-Spies E.E.,Whitney N.M.,Wanamaker A.D.,Griffin S.M.,Introne D.S.,&Kreutz K.J..(2020).A 250-Year, Decadally Resolved, Radiocarbon Time History in the Gulf of Maine Reveals a Hydrographic Regime Shift at the End of the Little Ice Age.Journal of Geophysical Research: Oceans,125(9).
MLA	Lower-Spies E.E.,et al."A 250-Year, Decadally Resolved, Radiocarbon Time History in the Gulf of Maine Reveals a Hydrographic Regime Shift at the End of the Little Ice Age".Journal of Geophysical Research: Oceans 125.9(2020).