As the world warms and scientists' warnings grow urgent, climate negotiators are counting down toward make-or-break talks later this year, hoping for progress on a long-term deal to sharply reduce greenhouse-gas emissions.
Experts are beginning to fear, however, that as time runs down the best that can be hoped for may be an extension of the relatively weak Kyoto Protocol, due to expire in 2012. The alternative is a world without any carbon-reduction rules at all.
The year's bad news on climate change is coming in installments.
In February, a UN-sponsored scientific network reported that unabated global warming would produce a far different planet by 2100, from rising seas, drought and other factors. In early April, the scientists said animal and plant life was already being disrupted.
In the third installment, coming Friday in Bangkok, Thailand, the authoritative panel is expected to say the world could still head off severe damage if all countries act urgently, with the best policies and technology, to rein in carbon dioxide and other heat-trapping emissions -- an improbable scenario.
There are signs of movement. In March, the European Union formally committed to at least a 20-percent cut in emissions, below 1990 levels, by 2020. The Democrats newly in control of Congress are pushing for mandatory caps on U.S. emissions. China is talking more seriously about controls.
"There's a lot happening. Whether that translates into a change in negotiating positions is a complicated story," said Leon Charles, a veteran negotiator for the Caribbean nation of Grenada who will have a lead role in the upcoming talks.
The key complication is a "you first" standoff between the United States, on one side, and China and the developing world on the other.
President Bush, who is expected to veto any Democratic effort to reduce carbon emissions, rejects the Kyoto Protocol and its mandatory cutbacks, complaining they would hobble the U.S. economy and should have applied to China, India and other industrializing countries that were exempted because they're poorer.
China, meanwhile, isn't expected to submit to an international regime unless the U.S. takes on a major commitment. It points to the fact that its per-capita emissions of carbon dioxide, byproduct of power plants, automobiles and other fossil fuel-burning sources, has stood at less than one-sixth the American per-person emissions.
"Prematurely" committing to mandatory cutbacks could keep China from climbing out of its poverty, the Beijing government said in a climate report April 23.
The Kyoto pact, a 1997 annex to a 1992 UN climate treaty, requires 35 industrialized nations to reduce greenhouse-gas emissions by, on average, 5 percent below 1990 levels by 2012. But specialists say 50-per cent reductions will be needed to stabilize concentrations of the global-warming gases in the atmosphere.
The annual UN climate conferences -- this year's is in December in Bali, Indonesia -- have made no real progress toward turning such deeper cuts into treaty obligations once Kyoto expires.
In a discussion forum that's a sidebar to the conference, government delegates have been talking about narrower, innovative ways for fast-developing countries like China to contribute without committing to blanket, quantified reductions.
"They could commit to a certain share of renewables," that is, a higher proportion of wind, solar or other non-carbon power sources in their energy mix, said Hermann E. Ott of Germany's Wuppertal Institute, which has conducted in-depth studies of post-Kyoto paths.
"You could also think of efficiency standards for electrical appliances," Ott said, "or measures for certain sectors -- for the steel industry, for example."
That non-negotiating forum ends this year. If, as expected, no mandate emerges in Bali to negotiate binding post-Kyoto targets, the UN process risks running out of time, given that it will take years to produce a new agreement and win ratification worldwide.
That would open a post-2012 gap -- a world without carbon-reduction rules -- that could wreck the emerging, Europe-centered market in trading carbon allowances among industries. The allowances would become unnecessary and worthless.
Elliott Diringer, international strategist at Washington's private Pew Center on Climate Change, said at Bali "it may be time to think about bridging strategies," that is, extending Kyoto's limited quotas past 2012 while working on deeper cuts.
Ott agreed a "bridge" looks ever more likely. He doesn't want to sound pessimistic, he said, but "it is important to stress that time is of the essence."