title: Variational Characteristics and Implications of Gaseous Elemental Mercury for Three Continuous Typhoons in China.
abstract: Coupling air pollutants with particular meteorological conditions can induce air pollution episodes. To our knowledge, how typhoons influence mercury (Hg) as an extreme weather phenomena has not been reported. Gaseous elemental Hg (GEM) was measured during a time period (from September 16, 2011 to October 9, 2011) that included three typhoons (Haitang, Nesat, and Nalgae) at the Wuzhishan National Atmospheric Background Station. The GEM concentration during these typhoons ranged from 1.81 to 4.73 ng/m(3) (2.97 ± 0.58 ng/m(3)), 1.27 to 4.42 ng/m(3) (2.69 ± 0.83 ng/m(3)), and 1.43 to 2.99 ng/m(3) (2.47 ± 0.32 ng/m(3)), which was higher than for the non-typhoon period (1.14-2.93 ng/m(3), 1.61 ± 0.52 ng/m(3)). Simultaneously, the three typhoon periods exhibited a significant positive correlation between the GEM concentration and wind speed. These results differ from the common belief that lower pollutant concentrations will occur due to a typhoon accelerating pollutant diffusion. Changes in the wind direction and long range pollutant transport from the Chinese mainland can reasonably account for this abnormality. There was a significantly positive correlation between the GEM and SO2, NO x , CO, and O3 levels during the three typhoons periods, which indicates they came from the same sources or areas. A backward trajectory analysis and the concentration weighted field at our monitoring site indicated that clean air masses mainly came from Southeast Asia or the southeast and northeast sea surfaces during non-typhoon periods, while polluted air masses came from the Chinese mainland during the three typhoon periods. The results implied that the increased GEM concentrations in the Wuzhi Mountain were caused by the long-range atmospheric transport of Hg from the Chinese mainland during the typhoon periods. The combustion of coal may be the main emission sources.
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China.|Institute of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730000, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China.
authors.forename: Jiaren
authors.initials: J
authors.lastname: Sun
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China. chenlaiguo@scies.org.|School of Environment Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China. chenlaiguo@scies.org.
authors.forename: Laiguo
authors.initials: L
authors.lastname: Chen
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China.
authors.forename: Yutao
authors.initials: Y
authors.lastname: Lei
authors.affiliation: Hainan Research Academy of Environmental Sciences, Haikou, 570206, China. 105411639@qq.com.
authors.forename: Donghai
authors.initials: D
authors.lastname: Xie
authors.affiliation: School of Environment Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
authors.forename: Jingyong
authors.initials: J
authors.lastname: Liu
authors.affiliation: Institute of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730000, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection (MEP), Guangzhou, 510655, China.
authors.forename: Zhencheng
authors.initials: Z
authors.lastname: Xu
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data; D002681:China; D055867:Cyclonic Storms; D004784:Environmental Monitoring; D008628:Mercury / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D008628:Mercury