气候变化领域集成服务门户(CCPortal): Spatial-temporal characteristics of particulate matters and different formation mechanisms of four typical haze cases in a mountain city

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DOI	10.1016/j.atmosenv.2021.118868
	Spatial-temporal characteristics of particulate matters and different formation mechanisms of four typical haze cases in a mountain city
	Lu H.; Xie M.; Liu X.; Liu B.; Liu C.; Zhao X.; Du Q.; Wu Z.; Gao Y.; Xu L.
发表日期	2022
ISSN	1352-2310
卷号	269
英文摘要	The mechanisms by which pollution forms and acts in mountain cities are unique and remain unclear owing to terrain and meteorological conditions in the mountains. This study investigates the pollution characteristics in Chongqing, a typical mountain city, over the period from 2013 to 2017. Routine observed surface meteorological data, CALIPSO data, ERA5 reanalysis data and the backward trajectory calculation were used for analysis and comparison among four typical pollution cases. The results can be summarized as follows: (1) Pollutants in firework and unfavorable weather condition case mainly originated from local emissions. Anthropogenic aerosols that were characterized by spherical and small particles were detected, which contributed to the higher atmospheric scattering ability. Meanwhile, high humidity was beneficial to hygroscopic growth, resulting in a mixture of haze and fog forming low-visibility conditions. The strong inversion of the upper-layer and the presence of high mountains meant that local pollutants became confined within the basin region, leading to the formation and maintenance of pollution. The important roles of the weather conditions that are associated with mountains, such as cold air damming, low-level jet, valley and gap wind, were also revealed by the variable pollution conditions. (2) Airflow originating from Guizhou, Guangxi, and Hunan, where numerous fire points were detected, transported pollutants that were released from straw burning through upper-lower layer transport to the basin during the straw burning case. The aerosols detected showed low depolarization but a high color ratio, which are the typical characteristics of smoke. The inversion layer did not cover the entire basin, indicating that smoke aerosols were transported by downdraft to mix with local pollutants. (3) During the dust case, large amounts of dust aerosols were detected reaching from the surface to the troposphere, with a special double-layer structure. A lower depolarization ratio but stronger scattering ability was observed for the dust aerosols above the study region, which was attributed to mixing with other aerosols and chemical processes. Secondary circulation occurred when the inversion layer was at around 700 hPa, bringing dust aerosols from around 850 hPa to the surface. This study provides an understanding of the optical properties of the various types of aerosols and highlights the importance of weather condition in the formation and maintenance of pollution events. The results emphasize the need for intense vertical measurement in mountain cities. © 2021 Elsevier Ltd
关键词	Aerosol optical property Particulate pollution Pollution transport Weather condition
语种	英语
scopus关键词	Aerosols; Atmospheric humidity; Atmospheric movements; Depolarization; Dust; Fog; Haze polution; Light scattering; Meteorology; Particles (particulate matter); Smoke; Visibility; Aerosol optical property; Chongqing; Dust aerosols; Formation mechanism; Meteorological condition; Particulate Matter; Particulate pollution; Pollution transport; Spatial-temporal characteristics; Terrain conditions; Landforms
来源期刊	ATMOSPHERIC ENVIRONMENT
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/248107
作者单位	Chongqing Institute of Meteorological Sciences, Chongqing, 401147, China; School of Atmospheric Sciences, Nanjing University, Nanjing, 210023, China; Chongqing Meteorological Observatory, Chongqing, 401147, China; Sichuan Meteorological Disasters Prevention Technology Center, Chengdu, 610072, China; Chongqing Center of Ecology Environmental Monitoring, Chongqing, 401147, China
推荐引用方式 GB/T 7714	Lu H.,Xie M.,Liu X.,et al. Spatial-temporal characteristics of particulate matters and different formation mechanisms of four typical haze cases in a mountain city[J],2022,269.
APA	Lu H..,Xie M..,Liu X..,Liu B..,Liu C..,...&Xu L..(2022).Spatial-temporal characteristics of particulate matters and different formation mechanisms of four typical haze cases in a mountain city.ATMOSPHERIC ENVIRONMENT,269.
MLA	Lu H.,et al."Spatial-temporal characteristics of particulate matters and different formation mechanisms of four typical haze cases in a mountain city".ATMOSPHERIC ENVIRONMENT 269(2022).