SAN FRANCISCO — Wildfires in California in 2018 released the rough equivalent of about 68 million tons of heat-trapping carbon dioxide — about the same amount of carbon emissions as are produced in a year to provide electricity to the state, U.S. Interior Secretary Ryan Zinke said Friday.

The carbon dioxide figure — based on data analyzed by the U.S. Geological Survey — is more than 15 percent of all emissions produced by California in a year, according to Zinke.

“We know that wildfires can be deadly and cost billions of dollars, but this analysis from the U.S. Geological Survey also shows just how bad catastrophic fires are for the environment and for the public’s health,” Zinke said in a statement.

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