NORWAY: November 20, 2007


OSLO - Governments have promised to try to avert "dangerous" climate change expected to bring about rising seas, droughts and floods, but have yet to agree on a common definition of where the danger starts.


The controversy surfaced after the unveiling of a UN report in Spain on Saturday that had stoked controversy about whether the world is set for "dangerous" climate change.

A 1992 UN climate convention, signed by more than 190 nations, sets its overriding goal as avoiding "dangerous" human interference with the climate system. Few governments have set a definition but are coming under pressure to do so.

"I think the world has to come to grips" with defining 'dangerous', said Rajendra Pachauri, the head of the UN climate panel after the unveiling of the report which predicts that the poor in Africa and Asia are among those most at risk.

But some other experts say a precise definition is impossible and could distract from efforts to cut emissions of greenhouse gases from factories, cars and power plants.

"'Dangerous' means different things to different people," said Yvo de Boer, head of the UN Climate Change Secretariat, urging governments to focus efforts on working out a tough long-term global deal to fight climate change beyond 2012.

"When it's so clear from the scientific evidence that we need to be developing the answer it strikes me as a bit of a waste of time to narrow down the definition of the problem," he told Reuters.

The European Union has said that any warming of the climate by more than 2 degrees Celsius (3.6 Fahrenheit) over pre-industrial levels would be a "dangerous" change, bringing more damaging heatwaves, storms, or water shortages.

De Boer noted that some countries believe limiting global warming to 2 degrees would cost too much while some Pacific island states fear they could be washed off the map by rising seas long before such a temperature rise.

Pachauri says the world should consider the most vulnerable people in working out the ethics of combating global warming.

And he will get to air that view loudly when he collects the Nobel Peace Prize in Oslo on Dec. 10 on behalf of the Intergovernmental Panel on Climate Change (IPCC), which is sharing the award with former US Vice President Al Gore.

The IPCC projects, for instance, that between 75 and 250 million people in Africa would face greater stress on water supplies by 2020. People living around major deltas of rivers in Asia could face ever more damaging storm surges and floods.

The IPCC report dodges a definition of "dangerous", saying that it "involves value judgments" beyond the remit of scientists.

Ottmar Edenhofer, chief economist of the Potsdam Institute of Climate Impact Research, said it was more important to decide on greenhouse gas cuts than to set a precise definition of "dangerous" change.

"In the end, we need a common understanding of the emissions reduction profile -- this is what we need and a better understanding about the costs," he said.

-- For Reuters latest environment blogs click on: http://blogs.reuters.com/environment/ (Editing by Sami Aboudi)


Story by Alister Doyle, Environment Correspondent


REUTERS NEWS SERVICE