INTERVIEW-World should halve greenhouse gases by 2050-UN

OSLO, March 28 (Reuters) - A new U.N. treaty to fight climate change should aim to halve greenhouse gas emissions by 2050, the U.N.'s top climate change official said on Friday.

Senior officials from up to 190 nations will meet from March 31-April 4 in Bangkok for the opening session of two years of meetings to work out a new global warming pact to widen and succeed the United Nations' Kyoto Protocol.

Yvo de Boer, head of the U.N. Climate Change Secretariat in Bonn, said that studies by the U.N. Climate Panel indicated that emissions of greenhouse gases had to peak within 10 to 15 years and halve by mid-century to avert the worst effects of warming.

"That for me personally is the measure of success," he told Reuters, saying the goals should be cornerstones of a broad treaty due to be agreed in Copenhagen in December 2009. "It's not going to be easy."

World emissions of heat-trapping gases, mainly from burning fossil fuels, are rising sharply despite efforts to avert a warming that could bring ever more droughts, disease, mudslides, heatwaves and rising ocean levels.

De Boer added that mid-term targets, such as 2020 for developed countries, may be harder to agree than a long-term 2050 goal that will be achieved by future generations. "It's the bit in between that's difficult," he said.

China, drawing level with the United States as the top emitter of greenhouse gases, urged rich nations in a statement to the Bangkok meeting to live up to a guideline they agreed last year of 2020 cuts of 25 to 40 percent below 1990 levels.

The Bangkok talks are the first of a series meant to end in December 2009 with agreement on a pact that will include actions by all nations.


Kyoto binds 37 rich countries to cut emissions by 5 percent below 1990 levels by 2008-12 and excludes the United States. President George W. Bush says Kyoto would cost jobs and wrongly omits 2012 goals for developing nations.

The Bangkok talks will work out details of talks this year, focusing on curbs on emissions, new green technologies, helping poor nations adapt to climate change and new finance and investments.

"I don't know if it will be possible or even maybe desirable to map out the work programme for the full period until Copenhagen: it might be better just to plan for 2008," de Boer said. After Bangkok, there will be U.N. meetings in June, late August and December this year.

De Boer said it would probably take until 2009 to see how far developed nations were willing to commit to action on cutting emissions. The European Union has agreed to cut emissions by 20 percent below 1990 levels by 2020, and by up to 30 percent if other rich nations follow suit.

But many nations, both rich and poor, are awaiting the policies of the next U.S. president. Republican candidate John McCain and Democratic hopefuls Barack Obama and Hillary Clinton have said they would do far more than Bush to curb emissions.

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Editing by Peter Millership,