Mountain Haze
Great Smoky National Park. Image courtesy NPS.
DB: This is Earth and Sky. In the 1930s, Franklin Roosevelt created Virginia’s Shenandoah National Park for its fantastic mountain vistas . . .
JB: On a clear day, you could see all the way to the Washington Monument in Washington, DC – over 100 kilometers or about 70 miles away. Now, summertime visibility in the mountains is often less than a quarter of that.
DB: Most of the haze over Appalachian Mountains parks – as well as over farmlands, suburbs, and cities across the U.S. – is air pollution. The Great Smoky and Shenandoah National Parks are the two most polluted parks in the country. In recent years, the Great Smokies has gone many weeks per year in violation of the national health standard for ground-level ozone. It rivals the dirtiest cities in the United States for unhealthy air.
JB: One reason is the parks’ geography. In Shenandoah National Park, prevailing winds bring pollution east from Pittsburgh, Cleveland, Chicago and Detroit. Scientists say this pollution is primarily sulfuric acid – the same fine particles that cause acid rain – formed from sulfur dioxide that’s emitted by coal-fired electrical power plants. So it helps to conserve electricity.
DB: Special thanks today to the U.S. Forest Service and to the National Fish and Wildlife Foundation – supporting the conservation of native fish, wildlife, plants and their habitats. We’re Block and Byrd for Earth and Sky.
The following individuals were interviewed for today’s show. Our thanks to:
William Glaze
Editor
Environmental Science and Technology
University of North Carolina – Chapel Hill
Chapel Hill, NC
Jeremy Kranowitz
Director, SE Clean Air Campaign
Izaak Walton League of America
Gaithersburg, MD
Dennis Lamb
Professor of Meteorology
Penn State University
The following books, articles and web sites were used in preparing this script:
Clear The Air – umbrella organization for a national coalition of environmental and conservation groups working on the problem of air pollution in our national parks.
““Out of Sight: Haze in our National Parks – How Power Plants Cost Billions in Visitor Enjoyment.”“:http://cta.policy.net/haze/full_report.pdf This really is the definitive report on the subject. (Clear The Air)
The press release is here.
Colorado State University – IMPROVE – A website that tracks visibility at national parks
““Power That Pollutes: Virginia’s Outdated Power Plants and the State of the Air”“:http://www.iwla.org/cleanair/reports.html by Jeremy Kranowitz
This report looks specifically at Virginia, but also looks at the variety of impacts caused by coal-fired power plants, including haze in Shenandoah National Park.
Author’s Notes:
Existing sulfur scrubber technology as well as switching to cleaner natural gas can remove over 90 percent of the visibility-harming sulfur emissions from an electric utility smokestack. Several significant policy options could encourage these developments.
Sulfur dioxide, an extremely harmful gas, converts to acidic sulfate particulate matter in the atmosphere, and is the principal cause of the thick haze. Nationally, power plants burning fossil fuels are responsible for 67 percent of the sulfur dioxide, 23 percent of the nitrogen oxide, 36 percent of the carbon dioxide and 33 percent of the mercury emitted.8,9,10 Coal-burning power plants built before 1980 stand out as the major sources of air pollution in the electric utility industry.
Regional haze has reduced annual average visibility in our national parks and wilderness areas to about one-third (west) to one-quarter (east) of natural conditions. For example, the average natural visual range in Virginia’s Shenandoah National Park and in the Great Smoky Mountains of Tennessee and North Carolina is about 80-90 miles, while average summertime visibility has been reduced to a paltry 12 miles.
Additional Teacher Resources
U.S. National Park Service, Nature & Science, Explore Air: Shenandoah National Park Air Quality Information Overview
This report explores the current air quality condition of Shenandoah National Park. Winds coming into the southern Appalachians carry emissions from the Tennessee, Ohio, and Mississippi River Valley, the industrial cities of the Southeast, the Gulf States, and the Northeast. The height and physical structure of the mountains, combined with predominant weather patterns, tend to trap and concentrate air currents. These air masses bring with them large amounts of human-made pollution.
MSNBC: Worst National Parks for Air Quality Listed
This report was authored by the National Parks Conservation Association and two smaller groups, the report concludes that air quality in the national parks has not improved even though Congress tightened the Clean Air Act in 1990.
U.S. National Park Service, Nature & Science, Air Quality: Great Smoky Mountains
Air pollution is shrinking scenic views, damaging plants, and degrading high elevation streams and soils in the Great Smoky Mountains. Even human health is at risk. This site discusses the fact that most of this pollution originates outside the park and is created by power plants, industry, and automobiles.
