气候变化领域集成服务门户(CCPortal): Negative carbon isotope excursions: An interpretive framework

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DOI	10.1088/1748-9326/ab3318
	Negative carbon isotope excursions: An interpretive framework
	Vervoort P.; Adloff M.; Greene S.E.; Kirtland Turner S.
发表日期	2019
ISSN	17489318
卷号	14 期号:8
英文摘要	Numerous negative carbon isotope excursions (nCIEs) in the geologic record occurring over 104-105 years are interpreted as episodes of massive carbon release. nCIEs help to illuminate the connection between past carbon cycling and climate variability. Theoretically, the size of a nCIE can be used to determine the mass of carbon released, provided that the carbon source is known or other environmental changes such as temperature or ocean pH can be constrained. A simple isotopic mass balance equation often serves as a first order estimate for the mass of carbon input, but this approach ignores the effects of negative carbon cycle-climate feedbacks. Here we show, using 432 earth system model simulations, that the mass of carbon release and associated environmental impacts for a nCIE of a given size and carbon source depend on the onset duration of that nCIE: the longer the nCIE onset duration, the greater the required carbon input in order to counterbalance the input of 13C-enriched carbon through carbonate compensation and weathering feedbacks. On timescales >103 years, these feedbacks remove carbon from the atmosphere so that the relative rise in atmospheric CO2 decreases with the nCIE onset duration. Consequently, the impacts on global temperature, surface ocean pH and saturation state are reduced if the nCIE has a long onset duration. The framework provided here demonstrates how constraints on the total nCIE duration and relative shape - together determining the onset duration - affect the interpretation of sedimentary nCIEs. Finally, we evaluate selected well-studied nCIEs, including the Eocene Thermal Maximum 2 (∼54 Ma), the Paleocene-Eocene Thermal Maximum (∼56 Ma), and the Aptian Oceanic Anoxic Event (∼120 Ma), in the context of our model-based framework and show how modeled environmental changes can be used to narrow down the most likely carbon emissions scenarios. © 2019 The Author(s). Published by IOP Publishing Ltd.
英文关键词	carbon cycle modeling; hyperthermals; negative carbon isotope excursions
语种	英语
scopus关键词	Isotopes; Carbon cycle models; Climate variability; Environmental change; hyperthermals; Isotopic mass balance; Negative carbon isotope excursions; Oceanic Anoxic Event; Paleocene-eocene thermal maximums; Environmental impact; Aptian; carbon cycle; carbon emission; carbon isotope; climate change; climate variation; environmental impact; geological record; modeling; Paleocene-Eocene boundary; paleoclimate; weathering profile
来源期刊	Environmental Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/154423
作者单位	Department of Earth and Planetary Science, University of California Riverside, Riverside, CA 92521, United States; School of Geographical Sciences, University of Bristol, Bristol, BS1 1SS, United Kingdom; School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom
推荐引用方式 GB/T 7714	Vervoort P.,Adloff M.,Greene S.E.,et al. Negative carbon isotope excursions: An interpretive framework[J],2019,14(8).
APA	Vervoort P.,Adloff M.,Greene S.E.,&Kirtland Turner S..(2019).Negative carbon isotope excursions: An interpretive framework.Environmental Research Letters,14(8).
MLA	Vervoort P.,et al."Negative carbon isotope excursions: An interpretive framework".Environmental Research Letters 14.8(2019).