A complex air-monitoring program exists in Yosemite National Park. The monitoring stations are part of either a federal or state network, primarily funded by the NPS Air Quality Division (NPS-AQD) and the California Air Resources Board (CARB). Monitoring locations within the park include Turtleback Dome where ozone, visibility, dry deposition, and meteorology are monitored; Yosemite Valley where PM 10, PM 2.5 (standing for Particulate Matter of sizes 2.5 and 10 microns), ozone, NOx (various nitrous oxides) and meteorology are monitored; and Hodgdon Meadow where wet deposition is monitored.

The air monitoring station on Turtleback Dome measures ozone, visibility, dry deposition, and meteorology. NPS Photo.