WASHINGTON – The perils of climate change are attracting much attention these days, with a popular award-winning movie on the subject, a United Nations panel emphasizing the dangers and widespread agreement among scientists that global warming presents a potentially catastrophic threat.

The concern has prompted a flurry of legislative activity on Capitol Hill, with four major bills, soon to be five, vying for support and votes, and some measure appearing likely to pass. But it remains unclear how strong it will be, how far lawmakers are willing to go in restricting U.S. industry, and whether President Bush will veto a bill in any case.

The documentary “An Inconvenient Truth” spearheaded by former Vice President Al Gore focused the nation’s attention more clearly on the issue, especially after it won two Oscars last month, but it is not the only catalyst. In the last month, a United Nations-sponsored Intergovernmental Panel on Climate Change released a study determining that the world’s temperature is rising and declaring with 90 percent certainty that human activity is the cause.

Nearly a dozen energy companies have joined with leading environmental groups to form the United States Climate Action Partnership, or USCAP, and have begun lobbying the federal government to institute strict standards for emissions reduction.

Meanwhile, in the absence of binding national standards, many states, on their own or in regional consortia, have adopted laws to regulate emissions. Individual cities have even imposed such regulations.

“Things are moving right now at an incredibly quick pace,” said Antonia Herzog, a scientist with the Natural Resources Defense Council, an environmental advocacy group. “I think the people in Congress who matter accept that global warming is a fact and are now trying to figure out how to address it in a responsible manner.”

However, turning that political potential into a nationwide law may take time, despite pledges from Senate leaders to address the issue and promises from House Speaker Nancy Pelosi, D-Calif., to bring a bill up for a vote on the House floor by the summer. Although U.S. industry is increasingly on board, there are several competing proposals for how to tackle the problem and Congress has a full agenda.

“It’s going to be very complicated, with a huge amount of political infighting,” said Myron Ebell, director of energy and global warming policy at the Competitive Enterprise Institute, a conservative think tank that opposes legislative efforts to combat global warming.

“We think we have a very good opportunity to stymie everything so that nothing will emerge.”

Although public interest in global warming is increasing, enacting emissions controls has proved a sluggish enterprise at best; there has not been a new, overarching law on the subject since the Clean Air Act of 1990. Today the challenge is building consensus in a Congress that includes global warming naysayers. Many environmentalists also worry that President Bush will veto any bill that requires emissions cuts, though the White House has not issued a specific veto threat.

There appears to be at least a basis for dialogue, however, as all the bills propose a “declining cap-and-trade” system. Under that approach, an overall emissions limit would be established for a subset of polluters. Companies could then engage in trade – that is, bidding, buying or selling permits – so each could continue to operate profitably while the overall level of pollutants would go down. Over time, as the cap is lowered, permits would either decrease in value or be removed from circulation.

“People are coalescing around that as the broad approach, though there are differences on the particulars,” said Eileen Claussen, president of the Pew Center on Global Climate Change. “There’s some sense in the business community and in Congress that this is a tried-and-true approach.”

It’s a tack that was used successfully to limit acid rain-causing emissions under the Clean Air Act.

“When given a clear goal and an opportunity for markets to develop the technology to meet the goal, we’ve always met them,” said Mark MacLeod, special projects director for Environmental Defense, an advocacy group. “There’s no reason to expect we couldn’t achieve the goal this time.”


The goals, however, differ from proposal to proposal. A bill offered by Sens. Barbara Boxer, D-Calif., and Bernie Sanders, I-Vt., would aggressively reduce emissions to 80 percent of 1990 levels by 2050. At the other end of the spectrum, a yet-unintroduced plan from Sen. Jeff Bingaman, D-N.M., ties emissions reduction to gross domestic product and does not guarantee any reduction in emissions.

The unlikelihood of one bill making its way to a floor vote in pristine form is keeping most watchers from expressly advocating any one approach.

There is much more than just an emissions cap to discuss, as each bill also brings its own priorities for research. A proposal by Sens. John McCain, R-Ariz., and Joseph Lieberman, D-Conn., includes controversial provisions for advancing nuclear technologies, while one from Sens. John Kerry, D-Mass., and Olympia Snowe, R-Maine, focuses on small businesses. Several reward companies for taking early action to curb emissions.

Some see this as an opportunity to change the nation’s energy habits more broadly.

“If we begin to tap not just energy efficiency, but solar power, wind energy, biofuels … we can make huge changes to cleaning up the environment, and in the process create millions of high-paying jobs,” Sanders said.

Some businesses seem willing to accept regulation in exchange for the promise of a foothold in the growing market for clean technologies. General Electric, a member of USCAP, earned about 7 percent of its 2006 revenue from so-called “ecomagination” projects – wind turbines, improved-efficiency jet engines and other clean technologies.

But too many incentives can corrupt the process, say those who are against Congress legislating a global warming solution.

“A lot of people have figured out that if cap-and-trade is set up in the right way, they can make a lot of money,” said Ebell of the Competitive Enterprise Institute. He speculated that big businesses calling for climate change laws were eyeing quick profits from government subsidies for clean technologies and Wall Street transaction payoffs, rather than making a bona fide environmental investment.