Climate report: Warmer, drier in the West | VailDaily.com

Climate report: Warmer, drier in the West

Bob Berwyn

Taking a broad look at the West’s four major river basins – the Columbia, Colorado, Missouri and Rio Grande – climate researchers have concluded that changes in temperatures and precipitation patterns are threatening the region’s snow and water resources.The latest report on the impacts of climate disruption was released Wednesday at a news conference in Denver by the Rocky Mountain Climate Organization. The year-old group, headed by Louisville resident Stephen Saunders, studies and publicizes the potential impacts of global warming on the Rocky Mountain region.”Scientists say that in the West human-caused climate change will lead to more heat, less snow, less water when we need it, and possibly more drought,” Saunders said. “Our analysis shows that this climate disruption is already under way. In the West’s four largest river basins, temperatures are up and snowpack levels are down.””All of us, water utilities included, act on the assumption that the future will be a lot like the past,” said Denver Water manager Chips Barry. “I’m now a lot less confident of that than I used to be. W know that global warming is occurring, and that means much greater uncertainty about our future water supplies.”The new report indicates that in each of the four river basins, the most recent five years was the hottest such period in the last 110 years. The warming was greatest in January, February and March. This pronounced seasonal effect is predicted by many greenhouse gas studies and global warming models and can, according to the report, be interpreted as a “signature of human-induced climate change.” This also is when warming has the greatest effects on snowpack levels. The report also shows how crucial snowpack levels have declined in the four river basins in recent years. In the Colorado River Basin, for example, the 1990-2005 average is 10.5 percent below the historical average. A link to the report, as well as related information, is available at http://www.rockymountainclimate.org. Vail, Colorado