Climate treaty talks mark some progress.

On Nov. 12, the United States signed the 11-month-old Kyoto Protocol, an accord to limit emissions of carbon dioxide and other greenhouse gases.

Although it has been signed by 60 countries, it has only been ratified to date by Fiji and by Antigua and Barbuda. U.S. ratification requires Senate action. Once it is ratified by at least 55 countries, the protocol becomes a binding treaty.

While last week's U.S. signing did not commit the world's leading greenhouse-gas polluter to any specific actions, it was necessary to revive stalled treaty deliberations then under way in Buenos Aires, according to Stuart E. Eizenstat, the chief U.S. negotiator. Two days later, diplomats from 170 countries ended the meeting with a report of substantial progress--in recognizing the most important conflicts on how to implement the most treaty and in setting a deadline of late 2000 for resolving them.

Emission credits proved one source of conflict. Under the treaty, industrial nations would have to cut their combined emissions to 5 percent below their 1990 levels, which is 29 percent below what has otherwise been projected for 2010. In Kyoto last year, industrial nations won the right to use certain foreign investments as write-offs against some of their mandated reductions. The industrial nations would work through a "clean development mechanism," or CDM, to fund low-emissions technologies in developing countries. Big polluters could also buy the right to emit the unused portion of another nation's pollution allowance (SN: 12/20&27/97, p. 388).

In June, however, U.S. negotiators began arguing that the United States should be able to write off all of its required reductions--not just some small share--through such foreign investments.

Many nations now view the United States as "reneging on its Kyoto commitments," says Philip Clapp of the National Environmental Trust in Washington, D.C. Speaking from Buenos Aires, he predicted that if the United States holds to its stance, it could kill hopes of advancing treaty negotiations next year.

Another potential deal breaker, says Connie Holmes of the Global Climate Coalition, a group of U.S. industrial firms, is an insistence by many developing countries that CDM rules be set before those for emissions trading. Unless the rules are developed in tandem, she fears, the more numerous developing countries may adopt rules that they want for the CDM investments and then boycott efforts to set up the emissions trading desired by industrial nations.

Under the treaty, developing countries would not be subject to specific emissions targets, only asked to slow their growing greenhouse emissions. Last week, however, two developing countries--Argentina and Kazakhstan--volunteered to accept emissions targets.

At the Buenos Aires meeting, Sen. John Kerry (D-Mass.) said that this "important break in the heretofore solid Block of 77" developing nations, which had argued against such limits, signifies major treaty progress.