Here's a positive move for the environment: California regains federal permission to set tougher auto pollution rules and zero-emission vehicle mandates than the government's national standards. The Environmental Protection Agency (EPA) said the most populous state can impose its own greenhouse gas tailpipe limits, reversing a 2019 rule that blocked states from doing so. The move puts California back at the forefront of combatting climate change in the U.S. It "could have a significant impact on the type of cars Americans will drive in the coming decade, the amount of gasoline the nation consumes and its ability to reduce the tailpipe emissions that contribute heavily to climate change," The New York Times says.

"We reinstate an approach that for years has helped advance clean technologies and cut air pollution for people not just in California, but for the U.S. as a whole," says Michael Regan, head of the EPA in Washington, D.C. The state's past ability to control vehicle emissions brought auto industry innovations as carmakers had to build cleaner cars for that huge market. One important example is catalytic converters, which convert toxic gases and pollutants in exhaust gas into less-toxic pollutants. Seventeen states and the District of Columbia have followed California vehicle standards adopted earlier, and 12 of them will apply that state's mandate to sell only zero-emissions vehicles after 2035. (Nonpolluting electric vehicles now make up just 4 percent of U.S. new car sales.)

The transportation sector is a major source of U.S. greenhouse gases in the U.S., representing 29% of America’s emissions. With over 14 million vehicles, California has by far the most car buyers nationally. Its congested freeways spew carbon pollution into the atmosphere and create smog-filled skies over Los Angeles and other cities. "You're not serious about climate change unless you're serious about completely transforming the transportation sector," says Gov. Gavin Newsom, D-California. After years of opposing federal rules to cut tailpipe pollution, many large automakers now embrace a future dominated by electric vehicles.

Governor says: "I thank the Biden Administration for righting the reckless wrongs of the Trump Administration and recognizing our decades-old authority to protect Californians and our planet. [It] comes at a pivotal moment underscoring the need to end our reliance on fossil fuels." – Gov. Gavin Newsom of California

EPA says: "We proudly reaffirm California's longstanding authority to lead in addressing pollution from cars and trucks. Our partnership with states to confront the climate crisis has never been more important." – Michael Regan, agency administrator

Senator says: "In addition to helping us meet our climate goals, this action will reduce pollution in communities across the country … and strengthen our nation's energy independence." – Sen. Tom Carper, D-Delaware