Scientists report on the future of California's water supply

San Diego News Network: Water flowing off the Sierra Nevada mountains, collecting in natural pools, stored in man-made reservoirs - it’s a refreshing picture until the water starts trickling through pipes to arid California communities, which will be one of the first regions of the world affected by global climate change, according to heavyweight scientists.

More than 65 scientists, academic leaders and policymakers from La Jolla to China and India gathered at UCSD for a three-day conference in early May to discuss the changing patterns of ice, snow and water in the Sierra Nevada mountains and Himalayan Asia that, in California, threatens to flood areas, heighten drought conditions and endanger fish stock.

The panelists issued a declaration summarizing their research in four sections: the problem, progress, conclusion and the future. The declaration will be presented at the Science and Technology in Society 2009 forum in Kyoto. “Human society and the global environment will be able to exist together, but this will only be achieved on a region by region basis as we saw at this workshop,” states the declaration. “A major failure in any one region will have serious global consequences.”

Climate change has disrupted weather patterns that affect water supplies; the evidence is clear in the first page of the three-page declaration under “problem:” “California is facing a serious drought. The Sierra Nevada snowpack, a vital summer water source already in decline, will be reduced by 40-90 percent by the end of this century. The Colorado River sometimes fails to reach the sea, as do many major rivers in China, including the Yellow River,” continued the declaration’s prognosis.

…The declaration concludes with the root of the problem: “Variations in precipitation and the melting of the ice and snow are caused by global temperature rise. Regionally, this is strongly affected by the influences of air pollution and dust on solar radiation, and changing weather patterns, such as the observed weakening and erratic timing of the monsoon.”….

Snow at the lake in Whyskytown Nation Recreation Area, California, National Park Service