For the United States to play a leadership role crafting a global warming treaty, negotiators say Congress and the Obama administration must enact limits this year to reduce emissions of greenhouse gases.
Among those pressing for a new U.S. law is Todd Stern, the Obama administration's envoy for climate talks that begin in December in Copenhagen, Denmark.
"The optimum would be legislation that is signed, sealed and delivered," Stern said Tuesday.
"It's been a long time now that countries have been looking for the United States to lead and take action," he said. "I think nothing would give a more powerful signal to other countries in the world than to see a significant, major, mandatory American plan."
International leaders attending a climate policy symposium on Wednesday echoed Stern's comments. They urged the U.S. to act despite a faltering economy.
"We are also being provided with an opportunity now to rethink business as usual," said Connie Hedegaard, the Danish minister for climate and energy. "Tackling global challenges, like that of the economy, we cannot do that without the United States. So we need the U.S. to engage."
Ed Miliband, British secretary of state for energy and climate change, said what Congress does to control domestic emissions will send a clear signal for the Copenhagen talks.
"The level of U.S. ambition that we see on this issue is very important because it will define and have an impact on the response that we see from other countries," Miliband said.
The Bush administration pulled out of the last global climate change treaty, the 1997 Kyoto Protocol, citing a lack of participation by developing countries and potential harm to the U.S. economy. In the 1990s, during the Clinton administration, the Senate balked at ratifying the agreement.
Meanwhile, emissions of greenhouse gases in the U.S. continue to rise. A draft of the latest greenhouse gas inventory released by the Environmental Protection Agency on Wednesday reports that emissions of heat-trapping gases grew 1.4 percent from 2006 to 2007. The bulk of that increase was carbon dioxide from the burning of fossil fuels to meet a greater demand for electricity.
Since 1990, U.S. emissions have risen 17.1 percent, the agency reported.
Stern acknowledged that a climate bill by year's end was a tall order, and said that if a bill didn't get done in time he'd like it as far along as possible.
House Democratic leaders are planning to take up legislation setting up a mandatory cap and trade system for greenhouse emissions sometime this summer. Senate Majority Leader Harry Reid has said he would like the Senate to vote on a bill after the August recess.
Under cap-and-trade, the government would establish a market for carbon dioxide by selling credits to companies that emit greenhouse gases. The companies can then invest in technologies to reduce emissions to reach a certain target or buy credits from other companies that already have met their emission reduction goals.
President Barack Obama has called for an 83 percent reduction in greenhouse gases from 2005 levels by the year 2050 using cap-and-trade. His recently released budget banks on raising $646 billion in revenues from 2012 to 2019 from auctioning emission credits to companies. The money would fund renewable energy projects and provide a tax credit to help families cope with higher energy prices.
But there is widespread dispute over the details of how cap and trade would work, with critics saying it would lead to higher costs for American consumers and could hurt an already bruised economy.
Duke Energy Corp. CEO Jim Rogers, a supporter of cap and trade legislation, previewed the debate to come. He said the Obama administration should redirect all money from the sale of credits to solving the "ecological crisis of our time."
Rogers said that as written now, Obama's budget would transfer wealth from the Southeastern and Midwestern states that depend more on coal for energy to coastal states where other fuels are used to produce electricity.