Gov. Arnold Schwarzenegger declared in his second inaugural address that California was both a "nation-state" and a "good and global commonwealth."

To that effect, Schwarzenegger will host his second annual international climate summit this week in Los Angeles, which organizers have billed as a precursor to United Nations talks in December to establish new worldwide emissions targets.

In a second term largely defined by the state's budgetary problems, the governor has staked much of his legacy on signing 2006 legislation committing California to reduce its greenhouse gases 25 percent by 2020.

Schwarzenegger won international attention for that law, in no small part because the governor was seen as an environmental Republican counterweight to President George W. Bush on greenhouse-gas restrictions.

A new Democratic president and a congressional effort to pass an emissions cap-and-trade plan could eventually overshadow California's efforts on the issue. And only nations can negotiate U.N. agreements on climate change restrictions.

But Schwarzenegger still believes that "subnational" governments such as states and provinces play a substantial role.

"The whole notion of subnationals convening is that states and cities can make agreements where nations are reluctant for one reason or another," said Dan Pellissier, Schwarzenegger's deputy Cabinet secretary. "Subnational groups can agree to work together to the extent possible without having to wait for national bodies to make commitments."

The Governors' Global Climate Summit 2 will have four days of events, including speeches from Schwarzenegger, former British Prime Minister Tony Blair and six other U.S. governors. All told, leaders from more than 70 states, provinces and countries are expected to attend.

Schwarzenegger wants subnational leaders to sign a joint statement declaring their commitment to reducing greenhouse gases through various means. Since states cannot change U.N. agreements, California is also working with African nations to submit language at the Copenhagen talks addressing how states and provinces can participate in emissions reductions, Pellissier said.

U.S. Environmental Protection Agency Administrator Lisa Jackson is scheduled to speak at Wednesday's official opening ceremony. That marks a change from a year ago, when Schwarzenegger battled Bush's EPA administrator in pursuit of a waiver that would allow California and other states to regulate vehicle greenhouse-gas emissions. The Obama administration has since granted the waiver.

"California's role in global warming policy has changed from being one of challenging the federal government to more of a partnership with the Obama administration," said Bill Magavern, director of Sierra Club California. "When Bush was president, it was important for California to show it is possible for governments to take action to curb greenhouse gases."

Environmentalists say that even with a friendlier White House in place, California and other states can play a significant role by experimenting with stricter climate change policies. They suggest Congress, which is focused on health care legislation, may not pass an emissions cap-and-trade bill this year.

"This is a very important laboratory for the world," said V. John White, an environmental lobbyist.

But California businesses, which opposed the state's greenhouse-gas reduction measures three years ago in Assembly Bill 32, say they prefer that California allow the federal government to install regulations rather than each state pursuing its own path. They say a patchwork of subnational regulations will hurt businesses in California.

"AB 32 certainly placed California as a leader in reducing greenhouse gases, but a lot has changed in the last three years," said Shelly Sullivan, spokeswoman for the AB 32 Implementation Group, which represents businesses and taxpayer associations. "California's economy has soured, unemployment has risen. ... But most importantly, the federal government has embarked on a global warming strategy. Continuing to pursue California-only restrictions will make California less competitive."

The conference is being sponsored by more than 40 businesses and nonprofit organizations, including Chevron Corp., the University of Phoenix and Sempra Energy. The California State Protocol Foundation, a nonprofit with ties to the California Chamber of Commerce and other business groups, solicited five- and six-figure donations earlier this year to pay for the event.

Donors are able to attend private receptions with the governor. Some, such as Edison International President and CEO Theodore Craver Jr., are scheduled to participate in workshops with leaders from international governments.

About 60 state employees working for Schwarzenegger and state entities such as CalEPA and the Air Resources Board have been organizing the event for months. The Protocol Foundation will pay for travel for Schwarzenegger employees, said Schwarzenegger spokesman Aaron McLear.

Call Kevin Yamamura, Bee Capitol Bureau, (916) 326-5548.