A Review of Atmospheric Mercury in the Polar Environment

Abstract

This paper is an overview of Hg measurements made in the Arctic and Antarctic regions, with an emphasis on the evaluation of the methodological approaches employed in both sampling and analysis between different Hg species as well as the fundamental aspects of their behavior. There have been numerous efforts to measure the concentrations of different Hg species, including gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate mercury (Hg(p)) in polar environments. The mean concentration value for GEM, if evaluated on the basis of numerous studies conducted previously, was moderately higher in the Arctic region (1.56 ng m⁻³) than the Antarctic counterpart with the limited data sets (1.08 ng m⁻³). The mean GEM concentration in the Arctic environment varied moderately between different locations so that the highest mean values occurred in sub-Arctic locations with a complicated climatology (e.g., Kuujjuarapik, Quebec: 1.80 ng m⁻³), while the lowest one was recorded in Pallas, Finland (1.26 ng m⁻³). A comparison of temporal patterns between different studies also indicates that rather dynamic variations occur due to the effects of certain phenomenon, known as atmospheric mercury depletion events (AMDE). During such depletion events, the GEM concentrations frequently dropped below 1.0 ng m⁻³, while the RGM and Hg(p) exhibited oposing trends. The distribution of GEM in polar environments is, however, fairly comparable in spatial scale, while those of RGM and Hg(p) vary fairly dynamically in such respects. Evidence suggests that the distribution of Hg species at each measurement site in the polar environments is affected more effectively by site-specific meteorological conditions.

KEY WORDS:

• gaseous elemental mercury
• reactive gaseous mercury
• particulate mercury
• Arctic
• Antarctic

ACKNOWLEDGMENTS

This work was supported by a Korea Research Foundation grant (KRF-2006-341-C00026) funded by the Korean Government (MOEHRD). The third author appreciates the partial support made by the Korea Research Foundation grant (KRF-2005-201-C00045) funded by the Climate Environment System Research Center and sponsored by the SRC program of Korea Science and Engineering Foundation.

Notes

∗List of matching references: (1) Kellerhals et al.^{[ 43 ]}; (2) Steffen et al.^{[ 112 ]}; (3) Lindberg et al.^{[ 63 ]}; (4) Aspmo et al.^{[ 7 ]}; (5) Berg et al.^{[ 12 ]}; (6) Temme et al.^{[ 115 ]}; and (7) Sprovieri et al.^{[ 109 ]}

^†Instrumental system used for the Hg analysis is CVAFS system with various models (2537A, 1130, or 1135); the capital letter T in the parenthesis denotes acronym for the manufacturer, Tekran.

‡The mercury concentration was reported as TGM.

^§ Munktell quartz filter W/Ni screen backing.

^‖ Whatman QM-A grade/quartz frit backing.

^# Quartz frit.

∗∗Gelman Type AE 61635.

^†† Teflon filters.

∗ Common period denotes all study periods, with or without any distinction of AMDE.

^† The results are originally reported as TGM concentration data.

^‡ All GEM data measured in Alert are shown in terms of individual annual mean values.

^§ The TGM concentration was averaged from seasons.

^‖ The mean was taken from the minimum Hg concentration in the spring of each year during 1995–2002, except for 2001.

∗Denotes the cases in which mercury concentrations were measured from precipitation samples.

∗Either GEM or TGM.