Among other goals, the legislation aims to reduce greenhouse-gas emissions across the US economy by 3 percent below 2005 levels by 2012, 20 percent by 2020, 42 percent by 2030, and 83 percent by 2050.
"We don't want to get out ahead or be at odds with what can be produced with legislation," said a senior administration official Monday. "So whatever number we put on the table will be with reference to what we think can come out of the legislative process."
These levels fall short of those embraced in the negotiating blueprint that countries drew up at global climate talks in Bali two years ago. That blueprint envisions developed countries cutting greenhouse-gas emissions by a collective 25 to 40 percent below 1990 levels by 2020, and by 80 to 95 percent below 1990 levels by 2050. Developing-country emissions would have to represent a "substantial deviation" from business as usual, rather than hew to specific emissions cuts.
Those figures represent the Intergovernmental Panel on Climate Change's assessment of what needs to be done if world leaders choose to cap global warming at roughly 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels.
The move represents the Obama administration's effort to try wield the key "to unlocking different aspects of the negotiations," says Sarah Ladislaw, a climate-change specialist at the Center for Strategic and International Studies in Washington. Among them: aid to developing countries for adaptation and to give them the wherewithal to afford the technologies they will need to meet any commitments.
Developing countries have been insisting that developed countries aim high in terms of cutting emissions – a sore point that led a group of African negotiators to briefly walk out on pre-Copenhagen talks in Barcelona earlier this month.
For months, Ms. Ladislaw says, the rest of the world has been waiting to hear what emissions targets the US is willing to put on the table.
Europe already has indicated it is striving to reduce EU emissions to 20 percent below 1990 levels by 2020 – and it has expressed a willingness to increase those cuts to 30 percent by then if other industrial countries adopt ambitious plans of their own. China has promised very ambitious goals for reducing its economy's energy intensity but as yet has presented no numbers. Russia has said it is willing to aim for 15 to 20 percent reductions over 2005 levels (which are now some 34 percent below 1990 levels, by some accounts). Japan has offered up a 25 percent cut below 1990 levels by 2020. Several other major developing countries also have put forward plans to slow the growth rate in their emissions.
While the numbers implied by the US Senate bill fall short of the aspirations set out in the Bali "road map" guiding the run-up to the Copenhagen meeting, this latest indication from the White house aims to show that the US is willing to take steps comparable with those of other industrial countries – provided Congress actually enacts a climate-energy bill.
Even with a Senate bill still a work in progress, "if you're the administration, you can go and tell a credible story that you have a plan" to reach the 2050 goals, says Andrew Deutz, a senior policy adviser for the Nature Conservancy. "Most of the countries coming to Copenhagen will come with new announcements. They'll all make contingent commitments. But this is really a positive negotiating dynamic."
Normally, the talks appear to be a race to the bottom, says Dr. Deutz, who has observed these talks since the first one in 1995. Instead, he continues, "we're seeing a race to the top. Everybody's trying to challenge everybody else to do more. That has a positive, ratcheting-up up effect in the negotiations. I find that to be really encouraging."
US negotiators include many people who took part in the effort to craft the 1997 Kyoto Protocol. They are acutely aware of the futility of negotiating a treaty that stands no chance of clearing the US Senate for ratification.
In the run-up to Monday's "on background" announcement from the White House, US negotiators had been pointing to the Senate bill whenever other countries brought up the subject of US emission-cutting goals. Now they have a somewhat more official pronouncement to work with.
The most international negotiators are hoping for now from Copenhagen is a political agreement on the main points in a new global warming treaty. Legal details would be left to work out later, either at a mid-2010 resumption of December's "recessed" talks or at the next ministerial-level talks in Mexico City in December 2010.
Meanwhile, the US Senate is not expected to act on its legislation – let alone reconcile it with the House version, which passed earlier this year – until early 2010. That makes the announcement risky for the US, says Ladislaw. If the final bill contains reduction targets that are lower than those in the current Senate legislation, the administration could be seen as failing to meet its political commitments – even if they were offered conditionally.
Still, "this is a game of inches," Ladislaw says. Echoing points of other analysts in recent days, she adds, the process "is closer to making concrete progress than it ever has been."
The process looks very incremental, even glacial, "in the court of public opinion," she explains. But if negotiators can reach political agreements on the main points, "it's a whole new negotiating environment," she says.
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