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Experts warn of 'abrupt' warming Experts warn of 'abrupt' warming
(about 7 hours later)
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. A UN panel has agreed a landmark report declaring that climate change is "unequivocal" and may bring "abrupt and irreversible" impacts.
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.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.
It declared the fact of global warming "unequivocal", and said it may bring "abrupt and irreversible" impacts. Among their conclusions are that carbon dioxide emissions are rising faster than they were a decade ago.
The text will be officially launched by UN chief Ban Ki-moon on Saturday.The text will be officially launched by UN chief Ban Ki-moon on Saturday.
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.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.
"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."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.
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.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 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 finalised late on Friday strengthens the language of those earlier reports with a warning that climate change may bring "abrupt and irreversible" impacts. 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.
"Approximately 20-30% of species assessed so far are likely to be at increased risk of extinction if increases in global average temperature exceed 1.5-2.5C (relative to the 1980-1999 average)," the summary concludes.
Other potential impacts highlighted in the text include:
  • between 75m and 250m people projected to have scarcer fresh water supplies than at present
  • yields from rain-fed agriculture could be halved
  • food security likely to be further compromised in Africa
  • widespread impacts on coral reefs
Writing in the International Herald Tribune ahead of the report's release, Ban Ki-moon said the world may be nearing a tipping-point on climate change.
"We all agree. Climate change is real, and we humans are its chief cause. Yet even now, few people fully understand the gravity of the threat, or its immediacy.
"Now I believe we are on the verge of a catastrophe if we do not act."
Local witnesses
His comments were endorsed by environmental groups on the fringes of the IPCC gathering.
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
"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 witnesses At a news conference, the 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.
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. 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 synthesis summary by the Nobel Prize-winning IPCC will be accompanied by a longer, more detailed document. The IPCC 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."