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Clean Air Status and Trends Network (CASTNET)

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CASTNET is a national monitoring network established to assess trends in pollutant concentrations, atmospheric deposition, and ecological effects due to changes in air pollutant emissions.

Clean Air Status and Trends Network (CASTNET)

Monitoring

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Maps & Charts

Publications

What's New

  • The 2018 CASTNET Annual Report is now available. Read about the significant decreases in sulfur and nitrogen pollutant concentrations since 1990. Ozone concentrations measured by CASTNET in the Eastern and Western U.S. were slightly higher in 2018 than 2017.
  • Recent Network Updates:
    • In November 2019, a monitoring site at Crater's of the Moon National Monument and Preserve (CRM435) joined CASTNET.
    • In July 2019, Grand Teton National Park (GRT434) joined CASTNET.
    • In April 2019, Death Valley National Monument (DEV412) was added to CASTNET. This site was also operated by the National Park Service from 1995-2007.

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