California greenhouse gas emissions fall — but not by much

New data show that California’s emissions of carbon dioxide and other heat-trapping gases started falling again in 2013. New data show that California’s emissions of carbon dioxide and other heat-trapping gases started falling again in 2013. Image 1 of / 1 Caption Close California greenhouse gas emissions fall — but not by much 1 / 1 Back to Gallery

Despite California’s many efforts to fight global warming, the state’s greenhouse gas emissions rose in 2012, as a nuclear power plant shut down and the drought hit hydroelectric dams hard.

But the increase, it turns out, didn’t last.

Data released by the state on Tuesday show that California’s emissions of carbon dioxide and other heat-trapping gases started falling again in 2013. The drop wasn’t much, just 0.3 percent. The state’s economy still pumped almost 460 million metric tons of greenhouse gases into the atmosphere, according to the California Air Resources Board.

But considering the circumstances, state officials still consider that a success.

The California economy grew 2 percent in 2013. At the same time, the deepening drought continued to cut the output of hydroelectric dams, forcing utilities to rely more on power plants burning natural gas. And the owners of the San Onofre nuclear plant north of San Diego decided to close the plant for good. All of those factors could have pushed greenhouse gas emissions higher.

Why didn’t they? The amount of renewable power generated within the state surged, with wind power production jumping 32 percent and solar rising 13 percent, according to the air resources board. And the state finally closed several old power plants that burned petroleum coke, a byproduct of the oil refining process.

“This inventory provides convincing evidence that California can grow its economy and continue to fight climate change,” said Mary Nichols, the board’s chairwoman. “No longer must economic growth result in smokestacks and pollution.”

California’s emissions peaked in 2004 at over 495 million metric tons and have since fallen 7 percent. But the state’s emissions are still higher than they were in 2010 — before the drought began — when they dropped to 456 million metric tons.

State law calls for cutting the state’s greenhouse gas emissions back to 1990 levels — an annual total of about 431 million metric tons — by 2020. And Gov. Jerry Brown has set a goal of reducing emissions 40 percent below 1990 levels by 2030.

David R. Baker is a San Francisco Chronicle staff writer. E-mail: dbaker@sfchronicle.com Twitter: @DavidBakerSF