U.N. climate chief skeptical about global carbon tax

By Deborah Zabarenko, Environment Correspondent

UNITED NATIONS (Reuters) - A top U.N. climate change official voiced doubt on Wednesday about a global tax on carbon, but said national taxes were possible and laws to cap global warming emissions were better for business.

"I personally am skeptical on the notion of global carbon taxes," said Yvo de Boer, who heads the U.N. Framework Convention on Climate Change.

International agreement on such a tax would take a long time, de Boer said, and it might take even longer to get the tax proceeds to the United Nations to deal with global warming.

Speaking at a news conference during the first full-scale U.N. meeting dedicated to climate change, de Boer said individual nations, including the Netherlands, have already put environmentally friendly taxes in place.

However, he said national taxes don't offer predictable progress in curbing the human-generated greenhouse gas carbon dioxide, though they may offer predictable revenues.

He favored so-called cap-and-trade laws, which limit carbon emissions and offer a way for those who emit more than the limit to buy carbon credits from those who emit less.

"What the business community is calling for at the moment is long-term certainty, clear emissions caps imposed by governments so that they know what kind of investment decisions they have to make," de Boer said.

The U.N. Intergovernmental Panel on Climate Change has said climate-warming emissions must be reduced by 50 percent by 2050, but without investment to curb climate change, emissions could rise by 50 percent instead, de Boer said.