ARLINGTON, Va. — Environmentalists and state officials from across the country called yesterday for federal approval of California’s bid to slow global warming by cracking down at the state level on certain automobile emissions.

Since the Bush administration has yet to launch its program against global warming, it should let California “blaze its own trail,” said Edmund G. Brown Jr., the state’s Democratic attorney general. “This is a worldwide crisis,” Brown told an Environmental Protection Agency air quality board.

Brown said EPA Administrator Stephen Johnson should “speak truth to power” — including the oil and automobile industries — by granting California the waiver it needs to impose reductions on tailpipe emissions of carbon dioxide and other “greenhouse” gases linked to global warming.

An automobile industry official countered that California’s “piecemeal” regulation of auto emissions would be costly and “counterproductive.”

There is “no question” that the proposed California rule would be this country’s leading initiative against global warming, said Rhode Island Atty. Gen. Patrick Lynch, who was among more than 40 witnesses who spoke at the daylong hearing. The California rules would help to “delay and moderate” the damage from global warming, Lynch, a Democrat, said, citing scientific studies.

If the EPA gives California the green light, the new tailpipe standards will immediately be adopted by 11 other states, including New York, New Jersey, Pennsylvania and every New England state except New Hampshire. Together, the 12 states generate 31 percent of the nation’s emissions of the greenhouse gases, according to Linda Adams, California’s environmental protection administrator.

The California plan would achieve “a small but significant” portion of the long-term, world-wide reduction in greenhouse gases that experts say is needed to prevent the worst effects of global warming, said Emily Figdor of the U.S. Public Interest Research Group.

Matt Auten of Environment Rhode Island estimated that by the year 2020, the California crackdown would help the United States attain about 8 percent of reduced emissions that are sought under the most ambitious global warming legislation pending in Congress.

The chairwoman of the Senate Environment and Public Works Committee and a chief sponsor of the leading Senate bill on global warming, Sen. Barbara Boxer, D-Calif., held a separate hearing yesterday on the California initiative. Sen. Sheldon Whitehouse, a committee member who is one of the co-sponsors of the Boxer bill, charged that “the EPA has sat on its hands,” regarding the California request for permission to implement its plan. EPA has done “little more than to issue a litany of excuses for its failure to respond to California’s request,” Whitehouse, a Democrat, said.

Because of its size and its reliance on automobiles, California has unique power under the Clean Air Act of 1970 to set tailpipe emission standards tougher than the federal government’s. The EPA has granted waivers over the years to let California impose its own anti-pollution regulations on cars; other states have tended to follow suit.

California Gov. Arnold Schwarzenegger invoked that power in December, 2005, when he sought an EPA waiver to let the state force auto makers to meet lower state standards of carbon dioxide and other emissions from cars produced beginning in model year 2009. The rules would affect cars, sport utility vehicles and light-duty trucks.

The Republican governor acted to enforce a 2002 state law that required automakers to cut carbon dioxide emissions by 25 percent from cars, and by 18 percent from light trucks and SUVs.

Adams, California’s top environmental official, speculated that the Bush administration is “looking for a reason” to reject California’s petition for the green light on its new tailpipe controls. She said that the EPA scheduled yesterday’s hearing only after Schwarzenegger threatened in late April to sue the government to secure its waiver.

But EPA spokesman John Millet said the agency delayed its ruling on California’s petition until the Supreme Court ruled on a pending Massachusetts case that had a direct bearing on the California matter. When the high court ruled last month, “this process got moving,” Millet said. “That’s why we’re having this hearing today.”

Meanwhile, President Bush has signed an executive order that gives federal agencies until the end of 2008 to study possible remedies for global warming.

In the Massachusetts case, the Supreme Court held that — contrary to the Bush administration’s argument — the EPA did have the power to enact regulations to stem global warming.

The sole witness against the California standard was Steve Douglas of the Alliance of Automobile Manufacturers. He argued that California has failed to show what effect its rules would have on global warming.

“A patchwork of state-level fuel economy regulations as is now proposed by California is not simply unnecessary, it’s patently counterproductive,” Douglas said. He said California makes “many assumptions and undocumented claims” about how its rules would affect global warming.

Lynch said Rhode Island seeks to adopt California’s auto-emissions rules because the state has so much coastline that “our very way of life” depends on climate stability.

Lynch said he left his children’s Little League game in Rhode Island Monday so that he could attend yesterday’s hearing. He said he explained to them that the “EPA has enormous power and I am going down there to challenge them to step up” and grant the California waiver. Turning to the air quality board at the hearing, Lynch said, “I’m asking you to do your job.”

jmulligan@belo-dc.com