气候变化领域集成服务门户(CCPortal): Mapping the drivers of uncertainty in atmospheric selenium deposition with global sensitivity analysis

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DOI	10.5194/acp-20-1363-2020
	Mapping the drivers of uncertainty in atmospheric selenium deposition with global sensitivity analysis
	Feinberg A.; Maliki M.; Stenke A.; Sudret B.; Peter T.; Winkel L.H.E.
发表日期	2020
ISSN	16807316
起始页码	1363
结束页码	1390
卷号	20 期号:3
英文摘要	An estimated 0.5-1 billion people globally have inadequate intakes of selenium (Se), due to a lack of bioavailable Se in agricultural soils. Deposition from the atmosphere, especially through precipitation, is an important source of Se to soils. However, very little is known about the atmospheric cycling of Se. It has therefore been difficult to predict how far Se travels in the atmosphere and where it deposits. To answer these questions, we have built the first global atmospheric Se model by implementing Se chemistry in an aerosol-chemistry-climate model, SOCOL-AER (modeling tools for studies of SOlar Climate Ozone Links-aerosol). In the model, we include information from the literature about the emissions, speciation, and chemical transformation of atmospheric Se. Natural processes and anthropogenic activities emit volatile Se compounds, which oxidize quickly and partition to the particulate phase. Our model tracks the transport and deposition of Se in seven gas-phase species and 41 aerosol tracers. However, there are large uncertainties associated with many of the model's input parameters. In order to identify which model uncertainties are the most important for understanding the atmospheric Se cycle, we conducted a global sensitivity analysis with 34 input parameters related to Se chemistry, Se emissions, and the interaction of Se with aerosols. In the first bottom-up estimate of its kind, we have calculated a median global atmospheric lifetime of 4.4 d (days), ranging from 2.9 to 6.4 d (2nd-98th percentile range) given the uncertainties of the input parameters. The uncertainty in the Se lifetime is mainly driven by the uncertainty in the carbonyl selenide (OCSe) oxidation rate and the lack of tropospheric aerosol species other than sulfate aerosols in SOCOL-AER. In contrast to uncertainties in Se lifetime, the uncertainty in deposition flux maps are governed by Se emission factors, with all four Se sources (volcanic, marine biosphere, terrestrial biosphere, and anthropogenic emissions) contributing equally to the uncertainty in deposition over agricultural areas. We evaluated the simulated Se wet deposition fluxes from SOCOL-AER with a compiled database of rainwater Se measurements, since wet deposition contributes around 80 % of total Se deposition. Despite difficulties in comparing a global, coarse-resolution model with local measurements from a range of time periods, past Se wet deposition measurements are within the range of the model's 2nd-98th percentiles at 79 % of background sites. This agreement validates the application of the SOCOL-AER model to identifying regions which are at risk of low atmospheric Se inputs. In order to constrain the uncertainty in Se deposition fluxes over agricultural soils, we should prioritize field campaigns measuring Se emissions, rather than laboratory measurements of Se rate constants. © 2020 Author(s).
关键词	aerosol agricultural soil atmospheric deposition atmospheric dynamics mapping selenium sensitivity analysis uncertainty analysis wet deposition
语种	英语
来源机构	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/132256
推荐引用方式 GB/T 7714	Feinberg A.,Maliki M.,Stenke A.,et al. Mapping the drivers of uncertainty in atmospheric selenium deposition with global sensitivity analysis[J]. Atmospheric Chemistry and Physics,2020,20(3).
APA	Feinberg A.,Maliki M.,Stenke A.,Sudret B.,Peter T.,&Winkel L.H.E..(2020).Mapping the drivers of uncertainty in atmospheric selenium deposition with global sensitivity analysis.,20(3).
MLA	Feinberg A.,et al."Mapping the drivers of uncertainty in atmospheric selenium deposition with global sensitivity analysis".20.3(2020).