San Francisco Chronicle: No state has done more than California to fight global warming. But a deepening drought could make that battle more difficult and more expensive.
A prolonged dry spell, stretching on for years, would slash the amount of power flowing from the state's hydroelectric dams, already running low after three parched winters.
The dams have, for years, been one of California's main sources of clean electricity, generating power without spewing greenhouse gases into the air. Drought forces utility companies...