In the first study comparing the impact of climate change across all 417 U.S. national parks, researchers report that the parks have seen double the national average temperature rise of 1ºC from 1895 to 2010. Parks also saw 12% less precipitation, compared to an average 3% drop in the rest of the country.

“National parks aren’t a random sample — they are remarkable places and many happen to be in extreme environments. Many are in places that are inherently more exposed to human-caused climate change,” said one of the study authors, Patrick Gonzalez of the University of California, Berkeley, in a statement. Gonzalez is also the Principal Climate Change Scientist of the U.S. National Park Service, though he notes in a lay summary of his paper that he does not represent the views of the U.S. Government.

A large area of the country’s national parks are in Arctic, desert, or alpine settings that are especially vulnerable to climate change. For example, the NPS reports that Joshua trees are having a harder time seeding because they are getting fewer freezing winter nights and trees are dying off. The Joshua Tree National Park in the southern California desert may one day be littered with the carcasses of its namesake.

Gonzalez’s team also used climate models to project possible future temperature and precipitation across American parks. In the most emission-intensive case they project temperature increases of between 3ºC and 9ºC. In the reduced-emissions scenario, they predict that temperatures would rise 2ºC in 58% of national park area, compared to 22% of total U.S. land area.

Such uses of climate change science have not generally found a warm welcome from the Trump administration. U.S. Geological Survey scientists provoked criticism from their boss for describing climate-related glacier melting as “dramatic” earlier this year. And the U.S. Department of the Interior, which oversees both the NPS and USGS, rescinded last year an Obama-era policy of using scientific evidence to set land management strategies.