I've been a member of the National Parks Conservation Association for years, and for years the nonprofit advocate for our national treasures has been warning that climate change threatens to destroy them.

Ten years ago, those warnings were more cautionary. But today they've become full-throated alarms that we may already be too late to prevent permanent damage to everything from Glacier National Park in Montana to California's Yosemite, the place where John Muir convinced President Teddy Roosevelt the importance of national parks. Now Yosemite's famed giant sequoias that dazzled Roosevelt are being threatened by climate change-induced wildfires.

Even Great Lakes national lakeshore parks are in peril, the Natural Resources Defense Council proclaimed 10 years ago. The warming climate is having a significant effect on the lakes' ecosystems, impacting fish, plants and everything that depends on them. This degradation includes Wisconsin's own Apostle Islands in Lake Superior, and the problems have only worsened since.

NPCA President Theresa Pierno warned in this month's National Parks magazine that national parks are warming twice as fast as the rest of the country.

The latest issue of The Week magazine expanded on why that's so. At America's national parks, extreme weather is triggering domino effects of disruption and devastation. In addition to the sequoias killed by California's wildfires, "heavy rains have led to colossal landslides at Denali National Park in Alaska and rising sea levels have caused the salinization of groundwater in Florida's Everglades, threatening endangered wildlife."

"Many of the 423 national parks are in arid, high-elevation regions, and thinner atmospheres and northern latitudes experience warming more rapidly," the magazine explained. "On average, park temperatures are up 2.2 degrees since 1895 — double the national rate." 

Beloved Yellowstone Park is a prime example. Earlier this summer a massive flood forced thousands of visitors to evacuate as surging waters swept away roads, cabins and bridges, causing roughly $1 billion in damage.

Winter at Yellowstone is, on average, 10 days shorter and less cold than it was just 70 years ago. Summers are warmer and drier. The Week added that a late snowfall this spring followed by warming and 5 inches of rain combined to rapidly melt the snowpack to create the catastrophic flood.

The rising temperatures are transforming the habitats at Yellowstone, the nation's oldest national park. Elk have decided to graze on private lands outside the park, bringing wolves with them.

"Snowpack is generally declining, reducing the flow of streams and rivers and allowing parasites and disease to flourish in Yellowstone's famous rainbow trout and mountain whitefish," the magazine's story noted. "Warmer temperatures allow the mountain pine beetle to better survive winter and reproduce longer. That native pest, in turn, destroys more whitebark pine, which is crucial to nutcrackers, grizzlies, and other wildlife."

The worry is that if Congress doesn't get its act together soon to address climate change, many of the parks will become inhospitable to visitors. Some scientists predict average temperatures at 62 parks will climb by an astounding 11 degrees.

It's essential that closed-minded politicians who refuse to lift a finger to address this lingering catastrophe be held to account. Yes, obstinate Democrat Joe Manchin has finally come around, but lockstep Senate Republicans who had enabled him for months need to pay the price for ignoring the biggest threat facing the country.

If our national parks and, indeed, so much of America is to be saved, it's painfully obvious that only American voters can make it happen.

Dave Zweifel is editor emeritus of The Capital Times. dzweifel@captimes.com, 608-252-6410 and on Twitter @DaveZweifel.  

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