Observations of atmospheric Hg species and depositions in remote areas of China

Abstract

From September 2007, we conducted continuous measurements of speciated atmospheric mercury (Hg) and atmospheric mercury depositions at five remote sites in China. Four of these sites were involved in the Global Mercury Observation System (GMOS) as ground-based stations. These stations were located in the northwest, southwest, northeast, and east part of China, respectively, which represent the regional atmospheric Hg budgets in different areas of China. The preliminary results showed that mean TGM concentrations were in the range of 1.60 - 2.88 ng m -3 , with relatively higher levels observed at sites in Eastern China and Southwestern China and lower levels at sites in Northeastern and Northwestern China. TGM concentrations at remote sites of China were also higher than those reported from background sites in North America and Europe, and this is corresponding very well with the Chinese great anthropogenic Hg emissions. Gaseous oxidized mercury (GOM) and particulate bounded mercury (PBM) were in the ranges of 3.2 - 7.4 pg m -3 and 19.4 - 43.5 pg m -3 , respectively. The preliminary result on precipitation showed mean precipitation THg concentrations were in the range of 2.7 - 18.0 ng L -1 .