Data for: Variation characteristics and source differences of gaseous elemental mercury in four seasons over Qingdao: Influence of weather processes
The variation characteristics and sources of gaseous elemental mercury (GEM) and other pollutions were studied in typical air pollution processes in four seasons. The results showed that GEM concentrations in autumn, winter, spring and summer were: 3.60±3.73, 1.33±0.62, 3.45±2.31, 2.20±1.36 ng/m3, respectively. The concentration of GEM in spring and autumn was higher than that in winter and summer. GEM daily variation was daytime controlled in four seasons. The concentration of GEM and pollutants was higher in polluted weather, which was controlled by the weather process affected by monsoon. The ratio of SO2/NO2 in winter and summer was 0.542 and 0.658 respectively, indicating that anthropogenic emissions such as coal-fired heating in winter and air-conditioning refrigeration in summer had high contribution to GEM. In winter, high pollutants, low GEM concentration and GEM/CO ratio were caused by the condensation of GEM under low temperature and adsorption of GEM on more fine particles. The GEM concentration was higher during the daytime, and the temperature was significantly positively correlated with GEM in four seasons (p<0.01), indicating that mercury re-emissions from the earth surface was the one of the main sources of GEM. Potential source contribution function analysis (PSCF) results showed that Shandong and Jiangsu province contributed more GEM than that from North China when autumn and winter pollution weather occurred. In spring, farther southern region such as Jiangxi, Zhejiang, Anhui, and Jiangsu contributed more GEM in polluted air. The adjacent southwest region contributed more GEM in polluted weather in summer.