Because the Trump Administration is unlikely to approve them, California believes it has no choice but to abandon its groundbreaking rules for zero-emission trucks and cleaner locomotives.

Gov. Gavin Newsom said California would fill the void for residents if the Trump administration kills a $7,500 E.V. tax credit.

As funds for climate change programs are cut, Democrats and environmentalists are pushing for a bond measure on the ballot to restore some funding.

The Bay Area Air Quality Management District has issued an air quality advisory for Thursday because of smoke from wildfires further north in California and southern Oregon that is expected to descend on the region.