Haleakala National Park Air Quality Information
Air quality in Haleakala NP is generally excellent, with few man-made sources of air pollution nearby. By far the largest source of air pollution is Kilauea Volcano on the island of Hawaii. Southeasterly “kona” winds transport volcanic gases and particles to Haleakala NP. This volcanic smog, or “vog,” contains sulfur dioxide, sulfuric acid, and sulfate particles and affects air quality and visibility. Locally, anthropogenic sources like power generating stations, sugar cane processing facilities and field burning, and automobiles can affect air quality and visibility.
The air quality related values (AQRVs) of Haleakala NP are those resources that are potentially sensitive to air pollution and include visibility and night skies, water quality, soils, vegetation, wildlife, and cultural resources.
Visibility is a very sensitive AQRV in Haleakala NP. Because the air is generally so clean in the park, just a small amount of pollutant particles can cause a noticeable haze. Volcanic smog from Kilauea Volcano is the most significant cause of visibility impairment. The Clean Air Act affords special protection to visibility in Class I air quality areas, so the park has a long-term visibility monitoring program. As part of the Interagency Monitoring of Protected Visual Environments (IMPROVE) network, visibility in Haleakala NP has been monitored using an aerosol sampler (1991-present) and an automatic 35mm camera (1987-1995).
Atmospheric deposition of heavy metals and organic compounds from trans-Pacific transport, and mercury from volcanic emissions may affect Haleakala NP aquatic and terrestrial resources and the wildlife that depend on them.
Ozone was monitored in Haleakala NP from 1991-1995. Measured ozone concentrations and cumulative doses were well below levels known to cause injury to vegetation.