Human activities are already changing the climate of the American West. This report by the Rocky Mountain Climate Organization (RMCO) and the Natural Resources Defense Council (NRDC), drawn from 50 scientific studies, 125 other government and scientific sources, and our own new analyses, documents that the West is being affected more by a changed climate than any other part of the United States outside of Alaska. When compared to the 20th century average, the West has experienced an increase in average temperature during the last five years that is 70 percent greater than the world as a whole. Responding quickly at all levels of government by embracing the solutions that are available is critical to minimizing further disruption of this region's climate and economy.

Temperatures in 2000-2007 Compared to 20th Century Averages

Hotter than the Rest

New research shows that Western states have been warming faster than the rest of the country. This map illustrates just a few of the ways the West is feeling the hurt.

Click on the states on the left to see more infomation.

Deadly Heat

In California, a heat wave in July 2006 killed at least 143 people, and possibly as many as 466.
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Vanishing Lake

Lake Powell in Arizona lost two-thirds of its water between 1999 and 2005, bringing the man-made Colorado River reservoir to an all-time low.


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Livestock Loss

Drought killed 150,000 cattle in Montana during a three-year period, bringing the state's cattle population to a 40-year low in 2004.
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No Snow

The snowpack at Snoqualmie Pass in Washington plummeted from an average peak of 92 inches to zero inches in 2005.
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Charred Habitat

Destructive wildfires in northern Nevada in 2006 charred antelope habitat and forced the relocation of half the regional herd.


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Grizzly Bears at Risk

Warmer temperatures in Wyoming have allowed mountain pine beetles to invade high elevations in the Yellowstone area, where they may eliminate whitebark pines, whose nuts are the most important food source for the area's grizzlies.


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Ruinous Wildfire

Colorado suffered the largest wildfire in its history in 2002: nine firefighters died, nearly 1,000 structures were destroyed, 915,000 acres burned, and $1.7 billion were lost in tourism revenue.


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Disastrous Drought

Drought hit Utah so hard in 2002 that every county in the state qualified for disaster relief. 2,600 Utahans lost their agricultural jobs, the harvest shrunk 30 percent and the state's pronghorn population dropped by 75 percent.


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Livestock Loss

New Mexico lost $279 million in income from livestock production due to the 2002 drought.
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Lost Revenue

Idaho was forced to cancel sage grouse hunting season after wildfires destroyed much of the bird's habitat in 2007.


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Melting Away

The glaciers on Oregon's Mount Hood have lost one-third of their surface area since the mid-1970s.
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Photo credits for interactive map: Forest fire, grizzly bear, ski lift: Corbis. Grass fire, bull calf, pronghorn: i-stock. Cracked earth, sun: Photodisc. Mount Hood: Gary Braasch