title: Automated Calibration of Atmospheric Oxidized Mercury Measurements.
abstract: The atmosphere is an important reservoir for mercury pollution, and understanding of oxidation processes is essential to elucidating the fate of atmospheric mercury. Several recent studies have shown that a low bias exists in a widely applied method for atmospheric oxidized mercury measurements. We developed an automated, permeation tube-based calibrator for elemental and oxidized mercury, and we integrated this calibrator with atmospheric mercury instrumentation (Tekran 2537/1130/1135 speciation systems) in Reno, Nevada and at Mauna Loa Observatory, Hawaii, U.S.A. While the calibrator has limitations, it was able to routinely inject stable amounts of HgCl2and HgBr2into atmospheric mercury measurement systems over periods of several months. In Reno, recovery of injected mercury compounds as gaseous oxidized mercury (as opposed to elemental mercury) decreased with increasing specific humidity, as has been shown in other studies, although this trend was not observed at Mauna Loa, likely due to differences in atmospheric chemistry at the two locations. Recovery of injected mercury compounds as oxidized mercury was greater in Mauna Loa than in Reno, and greater still for a cation-exchange membrane-based measurement system. These results show that routine calibration of atmospheric oxidized mercury measurements is both feasible and necessary.
authors.affiliation: Bingham Research Center, Utah State University , Vernal, Utah 84322, United States.
authors.forename: Seth
authors.initials: S
authors.lastname: Lyman
authors.affiliation: Bingham Research Center, Utah State University , Vernal, Utah 84322, United States.
authors.forename: Colleen
authors.initials: C
authors.lastname: Jones
authors.affiliation: Bingham Research Center, Utah State University , Vernal, Utah 84322, United States.
authors.forename: Trevor
authors.initials: T
authors.lastname: O'Neil
authors.affiliation: Bingham Research Center, Utah State University , Vernal, Utah 84322, United States.
authors.forename: Tanner
authors.initials: T
authors.lastname: Allen
authors.affiliation: Macquarie University , North Ryde, New South Wales Australia.|Department of Natural Resources and Environmental Science, University of Nevada, Reno , Reno, Nevada 89557, United States.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Miller
authors.affiliation: Department of Natural Resources and Environmental Science, University of Nevada, Reno , Reno, Nevada 89557, United States.
authors.forename: Mae Sexauer
authors.initials: MS
authors.lastname: Gustin
authors.affiliation: Department of Natural Resources and Environmental Science, University of Nevada, Reno , Reno, Nevada 89557, United States.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Pierce
authors.affiliation: Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, Maryland 20742, United States.
authors.forename: Winston
authors.initials: W
authors.lastname: Luke
authors.affiliation: Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, Maryland 20742, United States.|Cooperative Institute for Climate and Satellites, University of Maryland , College park, Maryland 20742, United States.
authors.forename: Xinrong
authors.initials: X
authors.lastname: Ren
authors.affiliation: Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, Maryland 20742, United States.|Cooperative Institute for Climate and Satellites, University of Maryland , College park, Maryland 20742, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Kelley
mesh_terms: D000393:Air Pollutants; D002138:Calibration; D004784:Environmental Monitoring; D008628:Mercury; D017669:Mercury Compounds
chemical_list: D000393:Air Pollutants; D017669:Mercury Compounds; D008628:Mercury