气候变化领域集成服务门户(CCPortal): A new approach of the normalization relationship between PM2.5 and visibility and the theoretical threshold; a case in north China

CCPortal

DOI	10.1016/j.atmosres.2020.105054
	A new approach of the normalization relationship between PM2.5 and visibility and the theoretical threshold; a case in north China
	Wu X.; Xin J.; Zhang X.; Klaus S.; Wang Y.; Wang L.; Wen T.; Liu Z.; Si R.; Liu G.; Zhao L.; Wang S.; Fan G.; Gao W.
发表日期	2020
ISSN	0169-8095
卷号	245
英文摘要	Both PM2.5 and visibility are important physical parameters to measure the air pollution condition. This paper first provided a new normalization approach for the relationship between PM2.5 and visibility in heavy pollutant region, which realized a mathematical calculation for two different physical parameters based on non-dimensional data process (also called Min-Max normalization). The normalization relationship showed a power function (y = axb) with high correlation coefficients. The inflection points of the maximum power function curvature composed the theoretical threshold range of PM2.5 for improving or deteriorating the visibility. In the case city of north China, the threshold range of PM2.5 was 112–121 μg·m−3 corresponding to the visibility range 4.5–5.9 km. Within the threshold range, the mean concentration of main pollutant components was 106 μg·m−3. The mean extinction coefficient, bext of 743.5 Mm−1, was mainly contributed by organic matter (34%), ammonium nitrate (19%), ammonium sulfate (18%) and elemental carbon (13%). When PM2.5 was below the range, the visibility increased significantly with the slow decrease of PM2.5. When PM2.5 exceeded the range, the visibility reduced seriously due to the saturated extinction contribution of the main pollutants. The new normalization approach theoretically revealed the significance of threshold and how to improve visibility by controlling PM2.5 at different pollution stages. © 2020 Elsevier B.V.
英文关键词	Maximum curvature; Normalization; PM2.5; Threshold; Visibility
语种	英语
scopus关键词	Nitrogen compounds; Pollution; Sulfur compounds; Correlation coefficient; Elemental carbon; Extinction coefficients; Inflection points; Mathematical calculations; Mean concentrations; Min-max normalizations; Physical parameters; Visibility; atmospheric pollution; concentration (composition); elemental carbon; organic matter; particulate matter; source apportionment; threshold; visibility; China
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/141833
作者单位	State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China; College of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu, 610225, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing, 210044, China
推荐引用方式 GB/T 7714	Wu X.,Xin J.,Zhang X.,et al. A new approach of the normalization relationship between PM2.5 and visibility and the theoretical threshold; a case in north China[J],2020,245.
APA	Wu X..,Xin J..,Zhang X..,Klaus S..,Wang Y..,...&Gao W..(2020).A new approach of the normalization relationship between PM2.5 and visibility and the theoretical threshold; a case in north China.Atmospheric Research,245.
MLA	Wu X.,et al."A new approach of the normalization relationship between PM2.5 and visibility and the theoretical threshold; a case in north China".Atmospheric Research 245(2020).