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Meteorological Data for Atmospheric Processes


The Clean Air Status and Trends Network (CASTNET) is a national network that assesses trends in pollutant concentrations, atmospheric deposition, and ecological effects due to changes in air pollutant emissions. The network collects data from across the United States.

The data at this resource include:

  • Aggregate Concentration Data
    • Concentration - Weekly: Weekly average dry ambient air concentrations from filter pack data
    • Ozone 8-hour daily max: Daily maximum value of the 8-hour rolling average
  • Measurement (Raw Data)
    • Filter Pack Concentrations - Weekly: Weekly ambient concentrations of SO2 and HNO3 gases, and SO4, NO3, NH4 and base cation concentrations for particles as measured by open-face filter packs.
    • Ozone - Hourly: Hourly ozone concentration data in parts per billion
    • Meteorological - Hourly: Hourly weather data
  • Prepackaged Data
    • Drychem: Raw IC concentration data from filter packs
    • Metdata: Hourly weather data
    • Model_output_Vd_2001: Hourly modelled deposition velocity values