The Atmospheric Mercury Network (AMNet) established this network of monitoring stations for the purpose of measuring atmospheric mercury fractions which contribute to dry and total mercury deposition. Sites will collect concentrations of atmospheric mercury species from automated, continuous measuring systems, concentrations of total mercury in precipitation, and meteorological measurements. Data will be collected with standardized methods, with quality assured data archived in an online data base.
AMNet has specific objectives:
- Measure atmospheric mercury concentrations of gaseous oxidized, particulate-bound, and elemental mercury in select locations
- Offer high-quality measurement data to estimate dry and total deposition of atmospheric mercury to other researchers
- Standardized operational methods so that instruments are being operated consistently
- Provide internal and external quality assurance
- Provide the data management capability and access
- Provide field support through an experienced site liaison
As with other networks, NADP welcomes the participation of other organizations and scientists. To truly understand the mercury problem, more monitoring information is needed.
Information on joining the network is available here.
Data Notices
Note of Sites Ending: There is an expectation that at the end of the federal year (Sept 30, 2024), two important AMNet sites will likely close: Mauna Loa (HI00) and Utqiagvik (AK95). These closings are due to high costs of keeping the sites operational within NOAA. If you are using these sites for your research, we are expecting this data to end soon. If you have concerns, please contact the Program Office.
Metadata
Maps / GIS
Annual Boxplots
The annual boxplots show the distribution of all valid measurements of Gaseous Elemental Mercury (GEM), Gaseous Oxidized Mercury (GOM), and Particulate Bound Mercury (PBM2.5) over the course of the entire calendar year. The GOM and PBM2.5is a direct measurement from a collection span of 2 hours (with some 1 hour measures). The GEM is an average of 12 measurements taken over the course of an hour, for every third hour.
The boxplots use a logarithmic scale for the Y axis, and display the following distribution values: (1) mean, (2) median, (3) 25th and 75th percentiles delineated by the box (middle 50% of the data), (4) the 10th and 90th percentile observations delineated by the whiskers, and (5) the extreme 10% of observations in both directions shown by the circles.
Maps requirements and methods have changed over time, which can change the map appearance from year to year. Individual chart descriptions may be found in the annual summaries in the documents section of this web site.
Please read our Use Conditions. before including these maps in publications.
Field Methods
Monitoring and analysis of elemental, gaseous oxidized and particulate Mercury fractions use a 2.5-micrometer impactor and KCl-coated annular denuder (for ionic mercury), thermally-desorbed particulate filter (for particulate-bound mercury), and gold traps (for elemental mercury). Analysis uses cold vapor atomic fluorescence spectroscopy (CVAFS).