Documents and files

Annual Reports

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NADP/NTN Assessing Trends in Precipitation Chemistry Across America1994


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Atmospheric Mercury Network Data Management Manual2011
Atmospheric Mercury Network Operations Manual2017


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Atmospheric Mercury Temporal Trends in the Northeastern United States from 1992 to 2014: Are Measured Concentrations Responding to Decreasing Regional Emissions?
Long-term atmospheric mercury measurements at Underhill, VT (VT99), and Huntington Forest, NY (NY20), from 1992 to 2014 and 2005 to 2014, respectively, were used to determine concentration trends using Mann−Kendall’s tau test with Sen’s slope estimator. These data, measured generally downwind of large Hg sources in the Midwestern United States, provide the longest record of ambient Hg concentrations available in the United States. At VT99, concentrations of gaseous element mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM) declined at rates of −1.8, −3.2, and −6.7%/year, respectively. At NY20, GEM and GOM concentrations declined at rates of −1.6 and −7.8%/year, respectively; however, PBM concentrations increased at a rate of 2.0%/year, which is likely related to winter wood burning. A trajectory ensemble analysis using the potential source contribution function indicates the source locations associated with high mercury concentrations changed from Toronto−Buffalo and Pennsylvania areas to east coast urban centers. The declining GEM concentrations in the northeastern United States are positively correlated with decreasing SO2 emissions in the upwind area. Overall, the results indicate that decreased mercury concentrations measured during the past decade are consistent with decreased Hg emissions from regional point sources and that increasing global emissions have not overwhelmed those decreases.
The Atmospheric Mercury Network: measurement and initial examination of an ongoing atmospheric mercury record across North America
An article describing the AMNet program including graphic summaries of data of 21 sites over 6 years for each species of mercury sampled.
Estimation of Speciated and Total Mercury Dry Deposition at Monitoring Locations in Eastern and Central North America
An article that discusses dry deposition of speciated mercury from 19 sites including VT99 (Underhill VT).


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