Sources and Dynamic Processes Controlling Background and Peak Concentrations of TGM in Nanjing, China

Autor: Casey B. Hall, Huiting Mao, Zhuyun Ye, Robert Talbot, Aijun Ding, Yang Zhang, Jialei Zhu, Tijian Wang, Che-Jen Lin, Congbin Fu, Xiuqun Yang
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Atmosphere, Vol 5, Iss 1, Pp 124-155 (2014)
Druh dokumentu: article
ISSN: 2073-4433
DOI: 10.3390/atmos5010124
Popis: Total gaseous mercury (TGM) data from urban Nanjing, at the western edge of the Yangtze River Delta (YRD) region in China, over nine months, were analyzed for peak and background mercury concentrations. The background concentration of TGM was found to be 2.2 ng∙m−3. In examining episodic influences of free tropospheric air masses on the surface TGM concentrations in Nanjing, we hypothesize heterogeneity in the global distribution of TGM concentrations in the free troposphere. The nine-month averaged diurnal cycles of TGM indicate a strong co-emission with SO2 and an underestimation of greater than 80% TGM emissions in current inventories. Regular peak concentrations of mercury were investigated and the major causes were YRD emissions, transport from rural areas, and monsoonal transport. Transport of rural emissions is hypothesized to be from illegal artisanal small-scale gold mining that are currently missing in the emission inventories. Enhancement of TGM associated with summer monsoon contributed to a maximum TGM concentration in mid-May–early June, an inverse seasonality in comparison to most other observations in China, North America, and Europe.
Databáze: Directory of Open Access Journals