San Jose is trying to lead the country in clean tech innovation. So how is the city doing?

They're out there... lurking in Earth's magnetic fields and damaging any satellite in their path.

The scientist dubbed "Dr. Doom" for his dire pronouncements about California's Sacramento-San Joaquin Delta is retiring after 33 years working on the troubled ecosystem that's central to California's water supply.

Not that long ago California’s herring population came perilously close to collapse. While their numbers are increasing, herring in the Bay are still struggling to return to their once prolific numbers.

For the first time in the Sierra Club's 120-year history, its national head was arrested for an act of civil disobedience. It signals a new, more aggressive stance for the organization spawned by John Muir.

They may sound like faulty plumbing, but male northern elephant seals have a unique communication system that's all about reputation.

Under a strategy known as "managed retreat," San Francisco gets ready to let the ocean reclaim a cherished stretch of Pacific coastline.

In November, California voters overwhelmingly passed Proposition 39, closing a corporate tax loophole and using the savings to create the largest state energy efficiency initiative in the country. Now the debate over how to use the money begins.

It's not the frenzy of 1849, but gold mining is quietly making a comeback in California. While some communities are concerned about the environmental costs, others see the chance for a "greener" gold rush.

Hydropower provides a good chunk of California's electricity. It relies on a balance of heavy snow in the winter and heavy runoff in the spring. Climate change threatens to throw that balance out of whack, a problem the government isn't examining.