LOS ANGELES -- California air regulators yesterday took up the world's most ambitious rules to reduce car emissions believed to contribute to global warming -- an effort that could have a sweeping effect on how the country fights vehicle pollution.
The regulations are fiercely opposed by the auto industry, which says the rules could lead to substantial increases in car prices. The industry has threatened to challenge the regulations in court if they are adopted.
The regulations could have a major impact in two ways: California represents 10 percent of the national auto market, and several other states follow California's lead when it comes to adopting their own clean air standards.
California is the only state able to set its own vehicle pollution standards because it began regulating pollution before the federal government. Other states can adopt either federal vehicle pollution standards or California's.
The state regulations would cut vehicle emissions by as much as 25 percent and require technological changes in vehicles starting in 2009. The innovations would include better air conditioners, more efficient transmissions, and smaller engines. Regulators estimate they would cut exhaust emissions by 25 percent in cars and light trucks and by 18 percent in larger trucks and SUVs.
''Obviously California cannot solve the problem of global climate change by ourselves. But we can certainly do our part," said Alan C. Lloyd, chairman of the Air Resources Board, which was holding public hearings yesterday and today. Board spokesman Jerry Martin said a vote on the proposal would probably occur today.
Auto industry officials say the rules unfairly target Californians for what is a global air pollution problem. California produces less than 1 percent of the greenhouse gases many scientists believe contribute to global warming.