Series: Park Air Profiles

Park Air Profiles - Olympic National Park

Hikers on the Hurricane Hill Trail
Visitors come to Olympic NP to enjoy scenic views of alpine lakes, forests, and wildlife in the Olympic Mountains.

Air quality at Olympic National Park

Most visitors expect clean air and clear views in parks. While air quality in Olympic National Park (NP), Washington, is relatively good, the east side of the park may be affected by emissions from populated and industrialized areas along the Puget Sound, including the Seattle metropolitan area and marine vessel traffic in the Strait of Juan De Fuca. Additionally, air masses originating in Asia transport pollutants across the Pacific Ocean and into the park (Yu et al. 2012). The National Park Service works to address air pollution effects at Olympic NP, and in parks across the U.S., through science, policy and planning, and by doing our part.


Mercury and toxics

Airborne mercury, and other toxic air contaminants, when deposited are known to harm birds, salamanders, fish and other wildlife, and cause human health concerns. These substances enter the food chain and accumulate in the tissue of organisms causing reduced reproductive success, impaired growth and development, and decreased survival.

Mercury and toxics effects:

  • Contaminants including mercury, current-use pesticides, historic-use pesticides, and industrial by-products have been found in snow, sediment, vegetation, and fish in the park (Frenzel et al. 1990; Hageman et al. 2006; Moran et al. 2007; Landers et al. 2010; Landers et al. 2008);
  • Mercury concentrations in fish are among the highest of eight western and Alaskan national parks studied. They exceed safe consumption thresholds for wildlife and humans, and current levels are associated with tissue damage in fish kidney and spleen (Landers et al. 2010; Landers et al. 2008; Schwindt et al. 2008).
  • Fish from contaminated lakes in Olympic NP displayed changes in metabolic, endocrine, and immune-related genes, compared to fish from uncontaminated lakes (Moran et al. 2007).
  • High mercury levels found in largemouth bass from Lake Ozette (inside the park) and Lake Dickey (outside the park). This coincides with logging in the lakes’ drainages which has greatly increased the amount of mercury entering the lakes (Furl et al. 2009).
  • Dragonfly larvae collected by citizen scientists from some sites at the park have elevated mercury levels. See project results.
Explore an interactive map of contaminant sampling in the Pacific Northwest.

Visibility

Vista of Olympic Mountains with avalanche lilies Clean, clear air is essential to appreciating the scenic vistas at Olympic NP.

Many visitors come to Olympic NP to enjoy views of the rugged Olympic Mountains. Park vistas are sometimes obscured by haze, reducing how well and how far people can see. Visibility reducing haze is caused by tiny particles in the air, and these particles can also affect human health. Many of the same pollutants that ultimately fall out as nitrogen and sulfur deposition contribute to this haze. Organic compounds, soot, dust, sea salt aerosols, and wood smoke reduce visibility as well. Significant improvements in park visibility have been documented since the 2000’s. Still, visibility in the park needs improvement to reach the Clean Air Act goal of no human caused impairment.

Visibility effects:
  • Reduction of the average natural visual range from about 140 miles (without the effects of pollution) to about 115 miles because of pollution at the park
  • Reduction of the visual range from about 105 miles to below 65 miles on high pollution days.
  • A 1990 study called PREVENT, the Pacific Northwest Regional Visibility Experiment Using Natural Tracers, found that sulfur (largely from power plants and urban emissions) is the largest contributor to reduced visibility at Olympic NP. Nitrates also contributed about 10% of the visibility reduction at the park and are mostly from emissions from pulp and paper mills or lime-kiln activity, fires, power plants, and transportation (Malm et al. 1994).

Visit the NPS air quality conditions and trends website for park-specific visibility information. Olympic NP has been monitoring visibility since 2001. Check out the live air quality webcam and explore air monitoring »

Nitrogen and sulfur

Excess nitrogen and sulfur compounds deposited from the air may have harmful effects. Nitrogen can cause changes to plant communities, with increases in exotic grasses and decreases in native species. Over-fertilization by nitrogen can also affect fish and amphibian populations. Healthy ecosystems can naturally buffer a certain amount of pollution, but as nitrogen and sulfur accumulate, a threshold is passed where the ecosystem is harmed. “Critical load” is a term used to describe the amount of pollution above which harmful changes in sensitive ecosystems occur (Porter 2005). Nitrogen deposition exceeds the critical load for one or more park ecosystems (NPS ARD 2018).

Nitrogen emissions in the Pacific Northwest are a concern for park managers (Fenn et al. 2003). Nitrogen deposition from urban, agricultural, and/or marine vessel sources could affect high elevation alpine vegetation and surface waters on the park’s east side (Eilers et al. 1994).

Nitrogen, together with sulfur, can also acidify surface waters and soils. Lakes and streams in Olympic NP are generally well-buffered from acidification, in part due to high rates of weathering and the chemical composition of local geology (Naiman et al. 1986). Some plants are sensitive to acidification, search for acid-sensitive plant species found at Olympic NP.

Visit the NPS air quality conditions and trends website for park-specific nitrogen and sulfur deposition information. Olympic NP has been monitoring nitrogen and sulfur deposition since 1980. Explore air monitoring »

Ground-level ozone

Quaking aspen tree Quaking aspen is one of the ozone sensitive species found at Olympic NP.

At ground level, ozone is harmful to human health and the environment. Ground-level ozone does not come directly from smokestacks or vehicles, but instead is formed when other pollutants, mainly nitrogen oxides and volatile organic compounds, react in the presence of sunlight. Ozone is transported to Olympic NP from the Puget Sound urban zone and trans-Pacific sources (Barna et al. 2000; Jaffe et al. 2003). Marine vessel traffic in the Strait of Juan De Fuca also contributes to ozone pollution in the region. However, ozone transport is limited and the Olympic Peninsula still has some of the lowest measured ozone concentrations in the Western U.S. (Bohm 1992).

Over the course of a growing season, ozone can damage plant tissues making it harder for plants to produce and store food. It also weakens plants making them less resistant to disease and insect infestations. Some plants are more sensitive to ozone than others. While several park species, including Populus tremuloides (quaking aspen) and Vaccinium membranaceum (thin leaved huckleberry) are known to be sensitive to ozone, concentrations at the park are below levels known to be harmful to plants (Eilers et al. 1994). Search additional ozone-sensitive plant species found at Olympic NP.

Visit the NPS air quality conditions and trends website for park-specific ozone information.

Barna, M., Lamb, B., O’Neill, S., Westberg, H., Figueroa-Kaminsky, C. Otterson, S., Bowman, C., and DeMay, J. 2000. Modeling Ozone Formation and Transport in the Cascadia Region of the Pacific Northwest. Journal of Applied Meteorology 39: 349–366.

Bohm, M. 1992. Air Quality and Deposition. In: Olson, R. K., Binkley, D. and Bohm, M. (eds). The Response of Western Forests to Air Pollution. Springer-Verlag: New York, NY. pp. 63–152.

Brace, S., Peterson, D. L., and Bowers, D. 1999. A guide to ozone injury in vascular plants of the Pacific Northwest. Gen. Tech. Rep. PNW-GTR—446. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 63 pp.

Eilers, J. M., Rose, C. L., Sullivan, T. J. 1994. Status of Air Quality and Effects of Atmospheric Pollutants on Ecosystems in the Pacific Northwest Region of the National Park Service. NPS Final Report. 255 pp. Available at https://irma.nps.gov/DataStore/Reference/Profile/547259.

Fenn, M., Geiser, L., Peterson, J., Waddell, E., and Porter, E. 2003. Why Federal Land Managers in the Northwest are Concerned about Nitrogen Emissions. National Park Service. 18 pp. Available at https://irma.nps.gov/DataStore/Reference/Profile/606872.

Frenzel, R. W., Witmer, G. W. and Starkey, E. E. 1990. Heavy metal concentrations in a lichen of Mt. Rainier and Olympic National Parks, Washington, USA. Bulletin of Environmental Contamination and Toxicology 44 (1): 158–164.

Furl, C. V., Colman, J. A., Bothner, M. H. 2009. Mercury Sources to Lake Ozette and Lake Dickey: Highly Contaminated Remote Coastal Lakes, Washington State, USA. Water Air Soil Pollut 208: 275–286.

Geiser, L. H., Jovan, S. E., Glavich, D. A., Porter, M. K. 2010. Lichen-based critical loads for atmospheric nitrogen deposition in Western Oregon and Washington Forests, USA. Environmental Pollution 158: 2412–2421.

Geiser, L. and Neitlich, P. 2007. Air pollution and climate gradients in western Oregon and Washington indicated by epiphytic macrolichens. Environmental Pollution 145: 203–218.

Hageman, K. J., Simonich, S. L., Campbell, D. H., Wilson, G. R., Landers, D. H. 2006. Atmospheric deposition of current-use and historic-use pesticides in snow at national parks in the Western United States. Environmental Science & Technology 40: 3174–3180.

Jaffe, D., McKendry, I., Anderson, T., Price, H. 2003. Six ‘new’ episodes of trans-Pacific transport of air pollutants. Atmos. Envir. 37: 391–404.

Kohut R.J. 2007. Ozone Risk Assessment for Vital Signs Monitoring Networks, Appalachian National Scenic Trail, and Natchez Trace National Scenic Trail. NPS/NRPC/ARD/NRTR—2007/001. National Park Service. Fort Collins, Colorado. Available at https://www.nps.gov/articles/ozone-risk-assessment.htm.

Landers, D. H., Simonich, S. M., Jaffe, D., Geiser, L., Campbell, D. H., Schwindt, A., Schreck, C., Kent, M., Hafner, W., Taylor, H. E., Hageman, K., Usenko, S., Ackerman, L., Schrlau, J., Rose, N., Blett, T., Erway, M. M. 2010. The Western Airborne Contaminant Assessment Project (WACAP): An Interdisciplinary Evaluation of the Impacts of Airborne Contaminants in Western U.S. National Parks. Environmental Science and Technology 44: 855–859.

Landers, D. H., S. L. Simonich, D. A. Jaffe, L. H. Geiser, D. H. Campbell, A. R. Schwindt, C. B. Schreck, M. L. Kent, W. D. Hafner, H. E. Taylor, K. J. Hageman, S. Usenko, L. K. Ackerman, J. E. Schrlau, N. L. Rose, T. F. Blett, and M. M. Erway. 2008. The Fate, Transport, and Ecological Impacts of Airborne Contaminants in Western National Parks (USA). EPA/600/R—07/138. U.S. Environmental Protection Agency, Office of Research and Development, NHEERL, Western Ecology Division, Corvallis, Oregon. Available at https://irma.nps.gov/DataStore/Reference/Profile/660829

Malm, W. C., Gebhart, K. A., Molenar, J., Eldred, R., Harrison, H. 1994. Pacific Northwest Regional Visibility Experiment Using Natural Tracers—PREVENT. National Park Service Final Report. Available at http://vista.cira.colostate.edu/Improve/final-report-prevent/.

Moran P. W., Aluru, N., Black, R. W., Vijayan, M. M. 2007. Tissue contaminants and associated transcriptional response in trout liver from high elevation lakes of Washington. Environ Sci Technol. 41(18): 6591–6597.

Schwindt, A. R., Fournie, J. W., Landers, D. H., Schreck, C. B., Kent, M. 2008. Mercury Concentrations in Salmonids from Western U.S. National Parks and Relationships with Age and Macrophage Aggregates. Environmental Science & Technology 42 (4): 1365–1370.

Sullivan, T. J., McDonnell, T. C., McPherson, G. T., Mackey, S. D., Moore, D. 2011a. Evaluation of the sensitivity of inventory and monitoring national parks to nutrient enrichment effects from atmospheric nitrogen deposition: main report. Natural Resource Report NPS/NRPC/ARD/NRR—2011/313. National Park Service, Denver, Colorado. Available at https://www.nps.gov/articles/nitrogen-risk-assessment.htm

Sullivan, T. J., McDonnell, T. C., McPherson, G. T., Mackey, S. D., Moore, D. 2011b. Evaluation of the sensitivity of inventory and monitoring national parks to nutrient enrichment effects from atmospheric nitrogen deposition: North Coast and Cascades Network (NCCN). Natural Resource Report NPS/NRPC/ARD/NRR—2011/330. National Park Service, Denver, Colorado. Available at https://irma.nps.gov/DataStore/Reference/Profile/2168709.

Sullivan, T. J., McPherson, G. T., McDonnell, T. C., Mackey, S. D., Moore, D. 2011c. Evaluation of the sensitivity of inventory and monitoring national parks to acidification effects from atmospheric sulfur and nitrogen deposition: main report. Natural Resource Report NPS/NRPC/ARD/NRR—2011/349. National Park Service, Denver, Colorado. Available at https://www.nps.gov/articles/acidification-risk-assessment.htm

Sullivan, T. J., McPherson, G. T., McDonnell, T. C., Mackey, S. D., Moore, D. 2011d. Evaluation of the sensitivity of inventory and monitoring national parks to acidification effects from atmospheric sulfur and nitrogen deposition: North Coast and Cascades Network (NCCN). Natural Resource Report NPS/NRPC/ARD/NRR—2011/349. National Park Service, Denver, Colorado. Available at https://irma.nps.gov/DataStore/Reference/Profile/2170593.

Sullivan T.J. 2016. Air quality related values (AQRVs) in national parks: Effects from ozone; visibility reducing particles; and atmospheric deposition of acids, nutrients and toxics. Natural Resource Report. NPS/NRSS/ARD/NRR—2016/1196. National Park Service. Fort Collins, Colorado. Available at https://www.nps.gov/articles/aqrv-assessment.htm

Trudell, S. A. and Edmonds, R. L. 2004. Macrofungus communities correlate with moisture and nitrogen abundance in two old-growth conifer forests, Olympic National Park, Washington, USA. Canadian Journal of Botany-Revue Canadienne de Botanique 82 (6): 781–800.