You don't usually hear a whole lot about what individual states are doing to tackle climate change. Surely those efforts, however noble, are just too small to matter—too local, too patchy. The only people who can really make a dent in U.S. energy policy are wandering around Capitol Hill, right? It's Congress or bust? Well, maybe. But that option's not looking too bright these days, given the fog around whether Congress will even pass a climate bill this year (or next year, or…). So maybe it's time to figure out if the states really could get together and pick up the slack.

The person to ask would be Terry Tamminen, who advised Arnold Schwarzenegger on climate policy back when California was drafting its plan to reduce carbon emissions 25 percent by 2020. Since then, Tamminen has traveled around the country trying to convince other governors to adopt their own climate plans—Florida's Charlie Crist was another early convert. When I asked him whether states could step up if Congress didn't pass a bill, he laughed and said I had the premise all wrong. "What they're doing is already genuinely significant," he explained. "You have thirty-three states with climate plans. These aren't just vague aspirational plans like you saw under the Kyoto Protocol, but concrete goals on efficiency, renewables—tangible things that are being written in law." Seven different states, for instance, are considering bills to set hard emissions targets, ala California's AB 32.

Indeed, looking around at everything being done on the state level, it does start to add up. Already, ten states in the Northeast have put their electric utilities under a cap-and-trade system known as RGGI. Eleven Western states and Canadian provinces are now laying the groundwork for their own cap-and-trade system, known as the Western Climate Initiative (WCI), which would begin in 2012 and could well expand further. Right now, there's a lot of cooperation between RGGI and WCI, Tamminen said—so that in the future they could be linked up, possibly with Europe's system, and possible with offset projects in, say, China and India. (Relatedly, Schwarzenegger is putting together an "R-20" for various subnational governments, modeled after the G-20, to get together and coordinate these sorts of regional efforts.)

Okay, but what sorts of cuts are we really talking about? The WCI, after all, includes some hefty states and provinces—California, Ontario, Washington, Arizona—but it doesn't include some of the heaviest polluters, like Alberta and Texas. Unfortunately, no one's done a full tally of the total impact on U.S. emissions—it's still too early for that. But, Tamminen notes, when you add state efforts to the hundreds of cities that have pledged to reduce their emissions, suddenly we're talking about a big swath of the United States. "Eighty percent of the country's emissions come from cities and industrial areas that are often located near those cities."

And, Tamminen adds, other states will have plenty of incentive to buy into these climate plans. For instance, some of the RGGI states have used revenue from selling carbon permits to help fill in their budget shortfalls ($100 million in New York's case)—an option that may increasingly look attractive to many governors around the country. It's a move that has a certain logic too it. "When you think about a coal-fired power plant," says Tamminen, "it's not just the greenhouse gases—there are all sorts of other pollutants causing asthma and so forth, and that ends up costing states in medical bills. So it's totally appropriate for states to offset those costs by forcing polluters to internalize them, through a price on carbon."

But that leads to another question: If so many states are already capping emissions and boosting alternative energy sources, why is it so hard to get anything through Congress? "Yeah," Tamminen sighs. "You'd think if thirty-three states have climate programs and a bunch of states are now doing cap-and-trade, it wouldn't be so hard for those state legislators and governors—many of whom are Republican, by the way—to convince their representatives. But the debate in D.C. doesn't really reflect the reality at the state level. Climate change has become a partisan issue. Even in Texas, you have guys like Rick Perry who's openly hostile to talk of climate change, even though his state's the largest producer of wind power in the country."

Still, it's hard to think that resistance will last forever. Looking back at the history of domestic policy, a lot of major national programs started out as state efforts, and then slowly ballooned over time until Congress finally took over. The Clean Air Act essentially started out as California smog effort. Likewise, in the 1980s, Ronald Reagan was against the idea of national appliance-efficiency standards until states had passed a jumble of different laws and industry groups finally lobbied for a single national standard. So, no matter what Congress does this year, the pressure from the states is going to continue being hugely important.

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