气候变化领域集成服务门户(CCPortal): A Changing Arctic Ocean: How Measured and Modeled 129I Distributions Indicate Fundamental Shifts in Circulation Between 1994 and 2015

CCPortal

DOI	10.1029/2020JC016740
	A Changing Arctic Ocean: How Measured and Modeled 129I Distributions Indicate Fundamental Shifts in Circulation Between 1994 and 2015
	Smith J.N.; Karcher M.; Casacuberta N.; Williams W.J.; Kenna T.; Smethie W.M.; Jr.
发表日期	2021
ISSN	21699275
卷号	126 期号:3
英文摘要	129I measurements on samples collected during GEOTRACES oceanographic missions in the Arctic Ocean in 2015 have provided the first synoptic 129I sections across the Eurasian, Canada, and Makarov Basins. During the 1990s, increased discharges of 129I from European nuclear fuel reprocessing plants produced a large, tracer spike whose passage through the Arctic Ocean has been followed by 129I time series measurements over the past 25 years. Elevated 129I levels measured over the Lomonosov and Alpha-Mendeleyev Ridges in 2015 were associated with tracer labeled, Atlantic-origin water bathymetrically steered by the ridge systems through the central Arctic while lower 129I levels were evident in the more poorly ventilated basin interiors. 129I levels of 200–400 × 107 at/l measured in intermediate waters had increased by a factor of 10 in 2015 compared to 1994–1996 owing to the circulation of the 1990s, 129I input spike. Comparisons of 129I distributions between the mid-1990s and 2015 delineate large scale circulation changes that occurred during the shift from a positive Arctic Oscillation and a cyclonic circulation regime in the mid-1990s to anticyclonic circulation in 2015. The latter is characterized by a broadened Beaufort Gyre in the upper ocean, a weakened boundary current and partial mid-depth, AW flow reversal in the southern Canada Basin. Tracer 129I simulations using the applied circulation model, NAOSIM, agree with both historical 129I results and recent GEOTRACES data sets, thereby supporting the present interpretation of the relationship of changes in arctic circulation to shifts in climate indices revealed by tracer 129I distributions. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	arctic; circulation; model; tracer
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/186417
作者单位	Bedford Institute of Oceanography, Dartmouth, NS, Canada; Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany; O.A.Sys – Ocean Atmosphere Systems GmbH, Hamburg, Germany; ETH Zurich, Zurich, Switzerland; Institute of Ocean Sciences, Sidney, BC, Canada; Lamont Doherty Earth Observatory of Columbia University, Pallisades, NY, United States
推荐引用方式 GB/T 7714	Smith J.N.,Karcher M.,Casacuberta N.,et al. A Changing Arctic Ocean: How Measured and Modeled 129I Distributions Indicate Fundamental Shifts in Circulation Between 1994 and 2015[J],2021,126(3).
APA	Smith J.N..,Karcher M..,Casacuberta N..,Williams W.J..,Kenna T..,...&Jr..(2021).A Changing Arctic Ocean: How Measured and Modeled 129I Distributions Indicate Fundamental Shifts in Circulation Between 1994 and 2015.Journal of Geophysical Research: Oceans,126(3).
MLA	Smith J.N.,et al."A Changing Arctic Ocean: How Measured and Modeled 129I Distributions Indicate Fundamental Shifts in Circulation Between 1994 and 2015".Journal of Geophysical Research: Oceans 126.3(2021).