Study details climate change effects on Sacramento-San Joaquin delta

California's water problems and the ecological pressure on the West Coast's largest estuary will intensify in a warming world, according to a first-of-its-kind scientific study.

The San Francisco Bay and the Sacramento-San Joaquin Delta will get warmer, saltier and clearer if global warming continues over the next several decades. That will increase the risk of extinction for some kinds of fish and could help unwanted species, including a toxic algae, flourish.

Flooding is likely to be more common upstream and along the coast, and water supplies will be stretched because of a shrinking snowpack, the researchers found.

In the delta, already seeing a broad ecological decline, the probability of further ecological surprises will increase.

"We're going to enter a new era of environmental conditions," said James Cloern, the study's lead author and a phytoplankton ecologist at the U.S. Geological Survey in Menlo Park.

Cloern said the seven-year study was the most complex research project he's undertaken in 36 years at the USGS. The researchers said their paper appears to be the first multifaceted assessment of how the estuary could respond to climate change.