Connecticut Hill Atmospheric and Precipitation Chemistry Research and Monitoring Facility
Institute of Ecosystem Studies

Site Description:

• One of the best studied sites in the U.S. for atmospheric deposition
• Location chosen to be uninfluenced by any local pollution sources such as power plants, urban centers, farms, or highways.
• Six hectare site surrounded by extensive forestlands in the 4500 ha New York State Connecticut Hill Game Management Area, as well as old fields and pastures. Both the landscape and land use are typical of other headwater sections of the Susquehanna River watershed in New York State.
• National Atmospheric Deposition Network (NADP), AIRMoN Site NY67 (wet precipitation quantity and chemistry on a daily basis: NO₃^-, NH₄⁺)
• Clean Air Status and Trends Network (CASTNet) site # CTH 110 (weekly dry acidic deposition: HNO₃ vapor, particulate NO₃^-, particulate NH₄⁺; weekly ozone)

Historical data available:

• Continuous operation since 1976
• Long-term record of N depostion (wet and dry)
• One of the original locations to measure regionally representative dry deposition in the U.S. (1987)
• Studies of throughfall versus inferentially measured dry deposition of N and sulfur species
• Isotopic studies (¹⁵N, ¹⁸O and ¹⁷O) of wet and dry deposition to understand the sources of NO_x deposition (e.g., vehicle emissions vs. non-vehicle sources)
• Impact of changing emissions of SO₂ and NO_x on wet and dry deposition of sulfur, nitrogen, and acidity.

Data to be collected for this project:

• Improve measurement of dry deposition of N, especially gaseous NO₂, NH₃. At least 1/3 of the measured total N deposition at the sites is in the form of dry deposition, but not all components have yet been measured.
• MARGA (Monitoring instrument for aerosols and gases) hourly sampling for gaseous NH₃, HNO₃, and HNO₂, and particulate NH₄⁺ and NO₃^-; ThermoElectron 42C-Y chemiluminescence detector for hourly sampling for NO_y
• Passive gas sampler monitoring for dry deposition of NH₃, NO₂, NO_x, HNO₃
• Comparison of data from passive samplers and CASTNet filter packs
• Further tests of spatial variability of dry deposition components

Images courtesy of (1) T. Butler (2) NADP (3) E. Boyer

Click the link to open a poster about the Connecticut Hill Facility (PowerPoint file)