Colorado River Basin Temperature Change 1908-2007 5-Year Average Temperatures Compared to 20th Century Average
The Rocky Mountain Climate Organization’s 2008 report, Hotter and Drier: The West’s Changed Climate, documents how climate change is already affecting the West, which has warmed more than most of the world. The greatest warming in the United States other than Alaska has been centered in the Colorado River basin. 2° F
The Colorado River Basin: 2.2°F Warmer in 2003-2007
1° F 0° F –1° F
Average temperatures for five-year periods – beginning with 1908-12 and through 2003-2007 – compared to the basin’s average 20th-century temperature. Data from the National Oceanic and Atmospheric Administration. Analysis by the Rocky Mountain Climate Organization. to refill them to capacity. Other reports of the RMCO have looked at climate change and its effects on wildfires in the West. Compared to the previous 17 years, the fire season of the last 17 years has increased by 78 days. Furthermore, the number of fires has increased fourfold, and nearly seven times as many acres have burned. While it is acknowledged that past
fire-suppression policies have been a factor, the overriding cause is the drying of fuels resulting from a 1.5-degree increase in average temperatures. Finally, according to another of the RMCO's reports, the Colorado State Forester blames an “unprecedented combination of drought and warm winters” for the infestation of 1.5 million acres of Colorado Chris Case
ters most in the basin: the volume of water in the Colorado River. Between 2000 and 2004, the river measured below-average flow for five straight years, a first since the start of modern records. The Colorado River’s two main reservoirs, Lake Powell and Lake Mead, are now only 45 and 50 percent full, respectively. It could take 15 to 20 consecutive years of what used to be normal inflow
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