气候变化领域集成服务门户(CCPortal): Tropospheric carbonyl sulfide mass balance based on direct measurements of sulfur isotopes

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DOI	10.1073/pnas.2020060118
	Tropospheric carbonyl sulfide mass balance based on direct measurements of sulfur isotopes
	Davidson C.; Amrani A.; Angert A.
发表日期	2021
ISSN	00278424
卷号	118 期号:6
英文摘要	Robust estimates for the rates and trends in terrestrial gross primary production (GPP; plant CO2 uptake) are needed. Carbonyl sulfide (COS) is the major long-lived sulfur-bearing gas in the atmosphere and a promising proxy for GPP. Large uncertainties in estimating the relative magnitude of the COS sources and sinks limit this approach. Sulfur isotope measurements (34S/32S; δ34S) have been suggested as a useful tool to constrain COS sources. Yet such measurements are currently scarce for the atmosphere and absent for the marine source and the plant sink, which are two main fluxes. Here we present sulfur isotopes measurements of marine and atmospheric COS, and of plant-uptake fractionation experiments. These measurements resulted in a complete data-based tropospheric COS isotopic mass balance, which allows improved partition of the sources. We found an isotopic (δ34S ± SE) value of 13.9 ± 0.1％º for the troposphere, with an isotopic seasonal cycle driven by plant uptake. This seasonality agrees with a fractionation of −1.9 ± 0.3％º which we measured in plant-chamber experiments. Air samples with strong anthropogenic influence indicated an anthropogenic COS isotopic value of 8 ± 1％º. Samples of seawater-equilibrated-air indicate that the marine COS source has an isotopic value of 14.7 ± 1％º. Using our data-based mass balance, we constrained the relative contribution of the two main tropospheric COS sources resulting in 40 ± 17% for the anthropogenic source and 60 ± 20% for the oceanic source. This constraint is important for a better understanding of the global COS budget and its improved use for GPP determination. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Anthropogenic sulfur; Carbonyl sulfide; Gross primary production; Oceanic sulfur; Sulfur isotopes
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180684
作者单位	Institute of Earth Sciences, Hebrew University of Jerusalem, Jerusalem, 95701, Israel
推荐引用方式 GB/T 7714	Davidson C.,Amrani A.,Angert A.. Tropospheric carbonyl sulfide mass balance based on direct measurements of sulfur isotopes[J],2021,118(6).
APA	Davidson C.,Amrani A.,&Angert A..(2021).Tropospheric carbonyl sulfide mass balance based on direct measurements of sulfur isotopes.Proceedings of the National Academy of Sciences of the United States of America,118(6).
MLA	Davidson C.,et al."Tropospheric carbonyl sulfide mass balance based on direct measurements of sulfur isotopes".Proceedings of the National Academy of Sciences of the United States of America 118.6(2021).