Daily Archives: February 2, 2008

A Future of Floods and Droughts

According to a recent scientific study, as reported in Science Daily, the water crisis in the Western United States is the result of human-induced climate change and will continue to get worse at current levels of global warming.

The team scaled down global climate models to the regional scale and compared the results to observations over the last 50 years. The results were solid, giving the team confidence that they could use the same models to predict the effects of the global scale increase in greenhouse gases on the Western United States in the future.
The projected consequences are bleak.
By 2040, most of the snowpack in the Sierras and Colorado Rockies would melt by April 1 of each year because of rising air temperatures. The earlier snow melt would lead to a shift in river flows.
The shift could lead to flooding in California’s Central Valley. Currently, state reservoirs are filled during the rainy season. As the water is drawn down, the reservoirs are replenished with snow melt from the Sierras.
If that snow melts earlier, as predicted in the climate models, the reservoirs could overflow.
“We are headed for a water crisis in the Western United States that has already started,” Barnett said. “A couple of decades ahead, we might not have that snowpack, making us more susceptible to flooding.”

The illustration accompanying the article juxtaposes aerial photos of South Cascade Glacier, Washington, making the case with stark visual contrast.