Back in May I wrote about the Park Service's take on air quality in the national park system. In that post, I questioned the agency's criteria for what constituted good air quality and how the agency determined that "100 percent" of the parks sampled met the agency's air-quality goals.
    A major problem I had with the report was the Park Service's determination that if an individual park's air quality remained stable from one year to another -- wasn't getting any worse, wasn't getting any better -- that the park had then met the agency's definition of success in terms of improving air quality.
    Well, now the National Parks Conservation Association is weighing in with its own report on air quality in the parks, and let's just say the advocacy group doesn't share the Park Service's rosy view of how clean and clear the air over our park system is.
    "Air pollution is among the most serious and wide-ranging problems facing the parks today," the NPCA report states. "Of the 390 parks within the national park system, 150 are located in parts of the country that fail to meet one or more national healthy air standards. In spite of a 30-year congressional mandate to restore pristine air to the parks for current and future generations, many of America's national parks remain plagued by airborne hazards."
    And that's just the introduction, folks.

    According to NPCA's own research, haze has cut views in many parks from 100 miles or more to just a handful of miles. That's something I can attest to, having stood in Sequoia and Mesa Verde national parks and struggled to see a mile or two. Too, the group says smog levels in some parks "rival those in America's most polluted cities."
    And it's not just the viewshed that's being harmed by air pollution.
    "Air pollutants can upset the balance of plant and animal life, while mercury and other toxins poison wildlife. Climate change, driven by emissions of greenhouse gases, threatens to cause some of the most profound and irreversible damage to the parks ever seen: Glaciers will disappear from Glacier National Park, and Joshua trees will disappear from Joshua Tree National Park," the NPCA states in the Turning Point report released today.
    While the group doesn't deny progress has been made, particularly thanks to the Clean Air Act's 1990 acid rain program, more needs to be done to reduce ozone damage to the parks; air-borne pollutants that harm vegetation and, in turn, wildlife; and haze that drastically reduces views.
    Major pollutants that are doing the most damage are sulfur dioxide and nitrogen oxides, which lead to acid rain that kills plants and fish, causes lung and heart damage in humans, erodes historic structures and monuments, and contributes to haze; carbon dioxide, which many believe contributes to global warming; and mercury, which poisons ecosystems and, if consumed in high enough levels, humans.
    To combat these problems, NPCA has outlined 10 steps:
        1. Clean up outdated power plants that are the largest industrial sources of sulfur, nitrogen, mercury and carbon dioxide emissions in the country.
        2. Require that new power  plans use the most effective pollution controls available.
        3. Set limits as to how much air pollution can be detected in our national parks.
        4. Ensure that legal limits on park air pollution are not exceeded.
        5. Require stronger power plant mercury controls.
        6. Address climate change by reducing carbon dioxide emissions.
        7. Expand air-quality monitoring programs in the parks and programs aimed at reducing air pollution in the parks.
        8. Promote clean, renewable domestic energy supplies.
        9. Fully fund the Park Service so it has the staff and finances to fulfill the agency's obligations under the Clean Air Act.
        10. Urge more Americans to become concerned about pollution levels in our parks and teach them how to be less polluting in their homes and businesses.
    You can read NPCA's 76-page report, which includes quite a few case studies in specific parks, here. And once you're done with that report, check out the Park Service's own air-quality study  and reach your own conclusion as to whether the glass is half full, or half empty, when it comes to the air in our parks.