Warming could erase California's farms

The Daily Green: In another sign that change has indeed come to the White House, President Obama's Energy Secretary, Stephen Chu, is discussing the threat of global warming in new, stark and -- frankly -- frightening terms. This is not the kind of warning we ever heard from the Bush Administration.

In an interview with the Los Angeles Times, his first since being confirmed as Energy Secretary, the Nobel Prize-winning physicist said that all agriculture in California could be undermined by global warming by the end of this century. In other words, within the space of one lifetime, the nation's largest farm producer -- known as the "salad bowl" because it provides about half of the nation's veggies -- could quickly become more like barren a dust bowl.

Not only that, but California's cities are in jeopardy, too, Chu said. The reason? Mountain snowpack in the Sierras is dwindling, as warmer temperatures prevent snow accumulation and lead to greater evaporation. It's the runoff from those mountain snows that irrigate land and keep thirsty people alive in the valleys below.

That's not a new warning. The declining spring runoff has been a significant factor in water stress, wildfires and other problems in California for several years. Gov. Arnold Schwarzenegger has been warning that California is already experiencing the ill effects of climate change, in the form of a year-round fire "season" and increasingly untenable divisions of water wealth.

California is in its third year of drought, and currently the snowpack holds only 61% of the water it holds in a normal year, according to a recent survey. The drought could become the worst in modern history, and as the climate continues to warn, severe drought could persist indefinitely, or recur more frequently....