VALENCIA, Spain - The UN's top climate official warned policymakers and scientists trying to hammer out a landmark report on climate change that ignoring the urgency of global warming would be "criminally irresponsible."
Yvo de Boer's comments came at the opening of a weeklong conference will complete a concise guide on the state of global warming and what can be done to stop the Earth from overheating. It is the fourth and last report issued this year by the Intergovernmental Panel on Climate Change, co-winner of this year's Nobel Peace prize.
Environmentalists and authors of the report expected tense discussions on what to include and leave out of the document, which is a synthesis of thousands of scientific papers. A summary of about 25 pages will be negotiated line-by-line this week, then adopted by consensus.
Rajender Pachauri, chairman of the Nobel Prize-winning panel, said scientists were determined to "adhere to standards of quality" in the report. It was indirect barb at the government representatives, who have been accused by environmentalists of watering down and excluding vital information from the summaries of earlier reports to fit their domestic agendas.
The document to be issued Saturday sums up the scientific consensus on how rapidly the Earth is warming and the effects already observed; the impact it could have for billions of people; and what steps can be taken to keep the planet's temperature from rising to disastrous levels.
The IPCC already has established that the climate has begun to change because of the greenhouse gases emitted by humans, said de Boer, director of the UN Framework Convention on Climate Change.
Everyone will feel its effects, but global warming will hit the poorest countries hardest and will "threaten the very survival" of some people, he said.
"Failing to recognize the urgency of this message and act on it would be nothing less that criminally irresponsible" and a direct attack on the world's poorest people, De Boer said.
The report will provide the factual underpinning for a crucial meeting next month in Bali, Indonesia.
That conference will begin exploring a new global strategy to curb greenhouse gas emissions after the 2012 expiration of the first phase of the Kyoto Protocol, the landmark agreement that assigned binding reduction targets to 36 countries.
The report will be the first to include a brief chapter on "robust findings and key uncertainties," in which the authors pick out what they believe are the most relevant certainties and doubts about climate change.
Among the uncertainties cited in an early draft obtained by The Associated Press: the lack of data from key areas of the world, conflicting studies on the effects of cloud cover and carbon soaked up by oceans, and projections on how planners in developing countries will factor climate change into their decisions.
The IPCC has already been criticized for the selectivity and language of the policy summaries, which have been softened on several points because of objections by countries including the United States, China and some big oil-producing nations such as Saudi Arabia.
On Monday, WWF International, one of several environmental groups invited to observe the process, said "governments cut vital facts and important information" during the negotiations.
Without naming them, the WWF accused governments of "politically inspired trimming" of facts from the summaries, which it said diluted the urgency to make deep cuts in emissions of carbon dioxide and other greenhouse gases.
De Boer said getting governments to sign off on the summaries is a critical element of the IPCC's value.
