Whether you believe in climate change or global warming doesn't really matter these days. Our climate is undergoing some significant change.

Evidence exists in melting icecaps, unusually potent storms, droughts, shifting seasons, and warming temperatures in general. Even if some of this change is natural, which is debatable, there is mounting evidence that human activity is a key driver in climate change. And, frankly, it wouldn't hurt for us all to strive to have less of an impact on the environment.

How global warming is affecting our national parks is a question that the National Parks Conservation Association explores in a special report.

Unnatural Disaster: Global Warming and Our National Parks not only sorts through a variety of answers to that question by pointing to on-the-ground trends being driven by the changing climate, but offers 10 straightforward suggestions that just might help the park system, and the rest of the world, cope with the changes.

Do you have to view the 48-page report as gospel? Not at all. But after you sift through it and look at what's going on in the parks, well, you just might agree that something is going on and it just might be prudent to address it.

Here are some of the changes NPCA believes are possible if nothing is done about climate change:

In Alaska, climate change could impact salmon fisheries such as those that surround Katmai National Park and Preserve. In California, warmer, drier weather not only could heighten the wildfire season in Yosemite, but it also could lead to greater insect damage to the forests and increase ground-level ozone problems in Sequoia.

In the East, droughts and warmer streams could decimate Shenandoah's trout fisheries, while the Blue Ridge Parkway could have to endure more air-quality problems stemming from higher ozone levels. Great Smoky Mountains might see its old-growth deciduous forests, great stands of hemlocks and Fraser fir, impacted by more ozone and insects. Rising sea levels could inundate Everglades National Park and Colonial Jamestown, while both Biscayne and Dry Tortugas could lose their coral reefs and sport fishing to warmer oceans.

Additionally, as we've noted before, Glacier's namesake rivers of ice are threatened by climate change, as are whitebark pine trees, which produce a nutritious nut that some grizzlies in Yellowstone and Grand Teton gorge themselves on in the fall. Just last week Yellowstone officials urged anglers to give the park's renowned trout fisheries a break during the hottest period of the day, as the rivers' temperatures were soaring and making life tough for the fish.

Here, via NPCA, is some of the evidence of global warming:

* Over the past century, the average temperature on Earth has risen 1.3 degrees Fahrenheit, and 11 of the last dozen years rank among the hottest on record since 1850.

* Green-house gas concentrations in the atmosphere are 70 percent higher than pre-industrial days.

* Sea levels are rising faster than they have over the past 2,000 years.

* Birds are altering their migration patterns, trees are leafing out earlier than usual, cold spells that once kept boring insects in check are no longer cold enough or long enough to do the job.

The changing climate figures to have long-lasting impacts, and not only to the environment. Biscayne National Park, for instance, generates nearly $24 million a year for the surround economies thanks to divers and snorkelers, according to NPCA. Can you imagine what would happen to those local economies if the colorful coral reefs that lure the divers and snorkelers died?

The Park Service doesn't question climate change, and has been studying ways to combat it. One approach has been to get the parks to be more "climate friendly."

"Although the situation seems dire, we can still halt the most severe effects of global warming if we take action now," says Tom Kiernan, NPCA's president. "The centennial anniversary of the national park system in 2016 provides sufficient time and a symbolically important deadline in which to act.

"Federal, state and local governments, along with individuals, can take actions within that timeframe that will slow and in some cases halt the damage," he adds. "Over the next time years, the national parks offer a unique opportunity to draw attention to America's priceless resources at risk, and to showcase opportunities to act to protect them."

So what's to be done? Well, the NPCA would like to see the following 10 steps implemented:

* Cap and reduce power plant emissions.

* Increase fuel efficiencies for the cars and trucks we drive.

* Develop more clean sources of energy.

* Boost funding for the National Park Service so the agency not only can stay atop maintenance needs but also "be at the forefront of research on the effects of climate change..."

* Expand the Climate Friendly Parks Program.

* Get states and local governments closely involved with battling climate change. It can be done. Look at what California is doing to reduce greenhouse gas emissions and how mid-Atlantic and New England states are working to cap carbon dioxide emissions from power plants.

* Help the parks adapt to climate change by building buffers around parks to prevent them from becoming islands surrounded by heat-storing urban areas.

* Work internationally to combat climate change. "The president must engage with our international partners to put in place meaningful and enforceable agreements for reducing greenhouse gases to a safe level."

* Invest in climate-friendly technologies, such as hydrogen-powered autos and zero emission power plants.

* Convince folks like you and me to join the effort by considering hybrid vehicles -- (although there are growing questions over how much they're helping) --, buying energy efficient appliances, driving less, and even turning off lights.

To those suggestions I'd add at least one more: let your congress-folk know climate change is an important issue that you want addressed. No doubt there are additional ways we can contribute to a cleaner environment -- recycling, stop buying bottled water, and carpooling are some examples -- but the key is that we do something.

"We have less than a decade remaining before the national park system's centennial," says Mr. Kiernan. "To make progress in protecting parks from global warming, we must now put into action a plan to protect national parks. That is our centennial challenge."