气候变化领域集成服务门户(CCPortal): A 30 -Year Time Series of Transient Tracer-Based Estimates of Anthropogenic Carbon in the Central Labrador Sea

CCPortal

DOI	10.1029/2020JC017092
	A 30 -Year Time Series of Transient Tracer-Based Estimates of Anthropogenic Carbon in the Central Labrador Sea
	Raimondi L.; Tanhua T.; Azetsu-Scott K.; Yashayaev I.; Wallace D.W.R.
发表日期	2021
ISSN	21699275
卷号	126 期号:5
英文摘要	We use a 30-year time series (1986–2016) of dichlorodifluoromethane (CFC-12) concentrations with a refined transit time distribution (TTD) method, to estimate the temporal variation of anthropogenic carbon (Cant) in the Central Labrador Sea. We determined that the saturation of CFC-12 and sulfur hexafluroide (SF6) in newly-formed Labrador Sea Water had departed significantly from 100% and varied systematically with time. Multiple linear regression of the time-varying saturation, with the tracer's atmospheric growth rate and the wintertime mixed layer depth as independent variables, allowed reconstruction of the saturation history of CFC-12 and SF6 in wintertime surface waters, which was implemented in the TTD method. Use of the time-varying saturation for CFC-12 gave Cant concentrations ∼7 μmol kg−1 larger than estimates obtained assuming a constant saturation of 100%. The resulting Cant column inventories were ∼20% larger and displayed lower interannual variability compared to conventional TTD-based estimates. The column inventory of Cant increased at an average rate of 1.8 mol m−2 y−1 over the 30-year period. However, the accumulation rate of Cant was higher than this average in the early 1990s and since 2013, whereas inventories remained almost unchanged between 2003 and 2012. The variation in the Cant accumulation rate is shown to be linked to temporal variability in the relative layer thickness of the annually ventilated Labrador Sea Water and the underlying Deep Intermediate Water. The non-steady Cant accumulation highlights the importance of sampling frequency, especially in regions of variable deep mixing and high carbon inventories, and potential misinterpretation of Cant dynamics. © 2021. The Authors.
英文关键词	anthropogenic carbon; CFC-12; Labrador Sea; SF6; transit time distribution method
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/186323
作者单位	Department of Oceanography, Dalhousie University, Halifax, NS, Canada; Division of Chemical Oceanography, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; Department of Fisheries and Oceans, Canada, Bedford Institute of Oceanography, Dartmouth, NS, Canada
推荐引用方式 GB/T 7714	Raimondi L.,Tanhua T.,Azetsu-Scott K.,et al. A 30 -Year Time Series of Transient Tracer-Based Estimates of Anthropogenic Carbon in the Central Labrador Sea[J],2021,126(5).
APA	Raimondi L.,Tanhua T.,Azetsu-Scott K.,Yashayaev I.,&Wallace D.W.R..(2021).A 30 -Year Time Series of Transient Tracer-Based Estimates of Anthropogenic Carbon in the Central Labrador Sea.Journal of Geophysical Research: Oceans,126(5).
MLA	Raimondi L.,et al."A 30 -Year Time Series of Transient Tracer-Based Estimates of Anthropogenic Carbon in the Central Labrador Sea".Journal of Geophysical Research: Oceans 126.5(2021).