This article is from the source 'bbc' and was first published or seen on . It will not be checked again for changes.

You can find the current article at its original source at http://news.bbc.co.uk/go/rss/-/1/hi/sci/tech/7098902.stm

The article has changed 15 times. There is an RSS feed of changes available.

Version 2 Version 3
IPCC to warn of 'abrupt' warming Experts warn of 'abrupt' warming
(about 5 hours later)
Climate change may bring "abrupt and irreversible" impacts, the UN's climate advisory panel is set to announce. A UN panel has agreed a landmark report on climate change, and says the world must act hastily to prevent the worst predicted effects coming to pass.
Delegates to the Intergovernmental Panel on Climate Change (IPCC) agreed a summary of its landmark report during negotiations here. After arduous talks in Valencia, Spain, scientists agreed a document they hope will shape debate on the next phase of the fight against climate change.
Discussions were said to have been robust, with the US and other delegations keen to moderate language. It declared the fact of global warming "unequivocal", and said it may bring "abrupt and irreversible" impacts.
The summary will be officially launched by UN secretary-general Ban Ki-moon on Saturday. The text will be officially launched by UN chief Ban Ki-moon on Saturday.
It brings together elements of the three reports that the Nobel Prize-winning IPCC has already released this year, on the science of climate change, impacts and adaptation, and options for mitigating the problem. Delegates to the Intergovernmental Panel on Climate Change (IPCC) summarised thousands of pages of scientific analysis, bringing together elements of the three reports already released this year, on the science of climate change, impacts and adaptation, and options for mitigating the problem.
Among its top-line conclusions are that climate change is "unequivocal", that humankind's emissions of greenhouse gases are more than 90% likely to be the main cause, and that impacts can be reduced at reasonable cost. "This is the strongest report yet by the IPCC - but says that there is still time to act," Bill Hare, an Australian climate scientist and one of the authors, told Reuters.
IPCC PROJECTIONS Probable temperature rise between 1.8C and 4CPossible temperature rise between 1.1C and 6.4CSea level most likely to rise by 28-43cmArctic summer sea ice disappears in second half of centuryIncrease in heatwaves very likely Increase in tropical storm intensity likely class="" href="http://news.bbc.co.uk/1/shared/spl/hi/guides/457000/457037/html/default.stm">Climate change: The evidence class="" href="http://newsforums.bbc.co.uk/nol/thread.jspa?forumID=3830&edition=1">Send us your comments The synthesis summary being discussed here in Valencia strengthens the language of those earlier reports with a warning that climate change may bring "abrupt and irreversible" impacts. Among the report's top-line conclusions are that climate change is "unequivocal", that humankind's emissions of greenhouse gases are more than 90% likely to be the main cause, and that impacts can be reduced at reasonable cost.
IPCC PROJECTIONS Probable temperature rise between 1.8C and 4CPossible temperature rise between 1.1C and 6.4CSea level most likely to rise by 28-43cmArctic summer sea ice disappears in second half of centuryIncrease in heatwaves very likely Increase in tropical storm intensity likely Climate change: The evidence Send us your comments The synthesis summary finalised late on Friday strengthens the language of those earlier reports with a warning that climate change may bring "abrupt and irreversible" impacts.
Such impacts could include the fast melting of glaciers and species extinctions.Such impacts could include the fast melting of glaciers and species extinctions.
"Climate change is here, it's impacting our lives and our economies, and we need to do something about it," commented Hans Verolme, director of the climate change programme with the environmental group WWF."Climate change is here, it's impacting our lives and our economies, and we need to do something about it," commented Hans Verolme, director of the climate change programme with the environmental group WWF.
"After this report, there are no politicians left who can argue they don't know what climate change is or they don't know what to do about it.""After this report, there are no politicians left who can argue they don't know what climate change is or they don't know what to do about it."
Local witnessesLocal witnesses
At a news conference, WWF presented testimonies from "climate change witnesses" in various parts of the world.At a news conference, WWF presented testimonies from "climate change witnesses" in various parts of the world.
Speaking by video link, Australian scientists and fishermen spoke of the changes they were seeing on the Great Barrier Reef. And Olav Mathis Eira, a Sami reindeer herder from Norway, said that his communities are seeing weather patterns unprecedented in their oral history.Speaking by video link, Australian scientists and fishermen spoke of the changes they were seeing on the Great Barrier Reef. And Olav Mathis Eira, a Sami reindeer herder from Norway, said that his communities are seeing weather patterns unprecedented in their oral history.
"Winter is one and a half months later than it used to be," he said. "We observed birds and insects that do not have a name in Sami." "Winter is one-and-a-half months later than it used to be," he said. "We observed birds and insects that do not have a name in Sami."
The 20-page IPCC synthesis summary is due to be accompanied by a longer, more detailed document, following discussions here. The 20-page synthesis summary by the Nobel Prize-winning IPCC will be accompanied by a longer, more detailed document.
The findings will feed into the next round of negotiations on the UN climate convention and Kyoto Protocol, which open in Bali on 3 December.The findings will feed into the next round of negotiations on the UN climate convention and Kyoto Protocol, which open in Bali on 3 December.
"The report sends a very strong signal to Bali," said Mr Verolme of the WWF. "Now it's up to the politicians."