• The Point Reyes Beach as viewed from the Point Reyes Headlands

    Point Reyes

    National Seashore California

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  • 2014 Changes to the Superintendent's Compendium

    Point Reyes National Seashore will be including an unmanned aircraft closure to the Superintendent's Compendium. The NPS invites the public to submit written suggestions, comments, and concerns about this change. Comment deadline is August 19. More »

Air Quality

Nature and Science

Air quality can dramatically impact views of the Seashore

Point Reyes National Seashore is a Class I park and air quality is generally good due to the prevailing westerly marine flows. However, during periods when atmospheric conditions displace the east Pacific high pressure system, air flows from the San Francisco Bay area can degrade the air quality of the seashore. This mainly occurs during the late summer and early fall, when the major atmospheric systems undergo a seasonal change. During this time, the seashore is often impacted by a general haze, which significantly impairs visibility.

Because ambient ozone levels at Point Reyes National Seashore are currently quite low, oxidant injury in vegetation is unlikely at the present time. If there were to be changes in the atmospheric patterns at the Seashore, there are approximately 37 plant and lichen species with known sensitivities to sulfur dioxide, ozone, and nitrogen oxides.

The National Park Service's Air Resources Division (ARD), in partnership with Colorado State University - Cooperative Institute for Research in the Atmosphere, produced an air quality podcast entitled "On the Air." This five minute web video provides an overview of air quality issues, research, and monitoring within the National Park Service system.

You can learn more at the ARD's Air Quality in Parks web site about how air pollution is affecting Point Reyes National Seashore and what the National Park Service is doing to address this issue.

Find out how pollutants including nitrogen, ozone, mercury, and fine particles affect resources such as streams, soils, and scenic vistas on the Air Resources Division's Point Reyes Air Pollution Impacts web page.

Scientific studies and monitoring are crucial to understanding the impacts of air pollution on the environment. Access air quality data and key references on the Air Resources Division's Point Reyes Studies and Monitoring web page.

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Did You Know?

Fog-filled valley with yellow twilight glow over a ridge in the background. © John B. Weller.

The rich, lush environment of Point Reyes heavily depends on the fog. During rainless summers, fog can account for 1/3 of the ecosystem's water input. But recent studies have indicated that there has been about a 30 percent reduction in fog during the last 100 years here in coastal California. More...