National Parks are warming twice as fast as the U.S. overall

Climate change poses the greatest threat to some of the country’s most prized areas

Photographs from 1938 and 2015 show the melting of Grinnell Glacier as seen from the summit of Mt. Gould in Glacier National Park. (Photos courtesy of T.J. Hileman, Lisa McKeon/U.S. Geological Survey)

Climate change is having an outsized impact on national parks in the United States, according to research conducted by scientists at the National Park Service, the University of California Berkeley and the University of Wisconsin Madison.

In a recently released paper, the researchers take the first comprehensive look at shifts in climate at all 417 sites managed by the National Park Service. The study, published in Environmental Research Letters, details changes that have occurred since the late 1800s and projects how the climate might further transform by the end of this century.

National park sites warmed at twice the rate of the United States overall between 1895 and 2010, the researchers found. Temperatures rose by about 1.8 degrees Fahrenheit per century in the parks, compared to less than 1 degree across the nation. The scientists attribute the lopsided trend to the fact that a large amount of National Park Service land is at high elevations or in the Arctic, where human-caused warming is accelerated. Indeed, the highest temperature hikes were in Alaska; Gates of the Arctic and Denali National parks, for example, both saw spikes of about 7 degrees Fahrenheit per century.

Future warming, of course, depends in part on how much humanity manages to curb greenhouse gas emissions. But even under the most optimistic projections, by 2100 more than half the of U.S. national park lands are expected to heat up by at least 3.5 degrees Fahrenheit — exacerbating problems like bark beetle outbreaks, increased wildfire and the loss of unique habitat critical to some species’ survival. Under gloomier scenarios, nearly 100 percent of the country, including its parks, would see that much warming.

“U.S. national parks protect some of the most irreplaceable ecosystems and cultural sites in the world,” the researchers write. Even as the nation contemplates a future too hot for Glacier National Park’s glaciers and too dry for Joshua Tree National Park’s Joshua trees, the researchers end their paper with a call to action: Reigning in emissions would temper the effects of climate change, “offering hope for the future of the U.S. national parks and the resources they protect for future generations.”

Emily Benson is an assistant editor at High Country News. Email her at emilyb@hcn.org.

This story was originally published at High Country News on Sept. 24, 2018.