Posted on 02/04/2008 4:55:40 PM PST by NormsRevenge
OSLO (Reuters) - Global warming this century could trigger a runaway thaw of Greenland's ice sheet and other abrupt shifts such as a dieback of the Amazon rainforest, scientists said on Monday.
They urged governments to be more aware of "tipping points" in nature, tiny shifts that can bring big and almost always damaging changes such as a melt of Arctic summer sea ice or a collapse of the Indian monsoon.
"Society may be lulled into a false sense of security by smooth projections of global change," the scientists at British, German and U.S. institutes wrote in a report saying there were many little-understood thresholds in nature.
"The greatest and clearest threat is to the Arctic with summer sea ice loss likely to occur long before, and potentially contribute to, Greenland ice sheet melt," they wrote in the journal Proceedings of the National Academy of Sciences.
"Tipping elements in the tropics, the boreal zone, and west Antarctica are surrounded by large uncertainty," they wrote, pointing to more potential abrupt shifts than seen in a 2007 report by the U.N. Climate Panel.
A projected drying of the Amazon basin, linked both to logging and to global warming, could set off a dieback of the rainforest.
"Many of these tipping points could be closer than we thought," lead author Timothy Lenton, of the University of East Anglia in England, told Reuters of the study.
Other sudden changes linked to climate change, stoked by human use of fossil fuels, included a dieback of northern pine forests, or a stronger warming of the Pacific under El Nino weather events that can disrupt weather worldwide, they wrote.
A possible greening of parts of the Sahel and the Sahara, if monsoon rains in West Africa were disrupted, was one of the few positive abrupt shifts identified by the scientists.
CLOSER
Even a moderate warming could set off a thaw of Greenland's ice sheet that could then vanish in 300 years -- raising sea levels by 6 meters (20 ft), or 2 meters a century and threatening coasts, Pacific islands and cities from Bangkok to Buenos Aires.
The U.N. Climate Panel foresees a rise in world sea levels ranging up to about 80 cms this century and reckons that a thaw of Greenland would take hundreds of years longer.
The new study said a disappearance of Arctic sea ice in summertime could happen in coming decades -- earlier than projected by the U.N. panel. That could stoke further global warming as dark water soaks up more heat than ice and snow.
The report also identified risks such as damage to northern pine forests -- widely exploited by the pulp industry -- because of factors such as more frequent fires and vulnerability to pests in warmer, drier conditions.
But it played down some other fears, such as of a runaway melt of Siberian permafrost, releasing stores of methane which is a powerful greenhouse gas.
And it said a shutdown of the Gulf Stream in the Atlantic Ocean that brings warm water north to Europe "appears to be a less immediate threat."
And the solution is to give all money and power to “Manbearpig”!
If Greenland melted down completely, 88% of the excess water produced could be contained by flooding the uninhabited Qatarra Depression in northwest Egypt, producing thousands of miles of valuable lakefront property, generating electrical power as water flowed from the Medditerranean to the depression and potentially turning much of the surrounding Sahara Desert into arable land.
It took Greenland 18,000 years to accumulate as much ice as it has now. How long do you think it will take it to melt?
If this scare scenario is for real, why aren't any of them talking about digging the ditch?
Have no fear, the Goracle will save us. /sarcasm
Pray tell how the polar bears made it through all the other climate cycles for the last several millions of years????
Libtards love to give away all your money, and worry about things they have no control of, but would like for you to believe they can contol you!
For a moment I thought this was and article about frat-initiation cow tipping in Greenland.
One marker for the fact you're dealing wih an unethical huckster of junk-science is the readiness to traffic in drug-store paperback cliches as if they mean something.
"Tipping points" is one recent addition to the phoney baloney pseudo-intellectual lexicon.
that is an understatement - however, prior to the advent of this UN/Gore hysteria scientists used to teach that there are cycles and rhythms to nature both climate, biological and other areas. I still do believe these things are part of that cycling and rhythmical sequence.
Lies only last as long as the public are not paying attention. Of late, the public IS paying more attention. And, the press is getting a deservedly tarnished reputation.
Congressman Billybob
The magnetic poles shifting into Siberia has not been mentioned in this article. The Sun’s increased out put will never be mentioned. I guess people do these things to the solar system. I fart and the Sun makes it hotter so run your hydrogen vehicle on a system that requires fossil fuels to make the hydrogen. Weren’t we all supposed to have personal airplanes by now? This is 2008 after all.
Good god, this reads like a stupid psychic reading rather than a science article. Tipping points, thresholds, blah blah blah yada yada yada. Sounds like astrology.
I worry about the “Tipping Point” for these peoples logic. The point where up becomes down and left becomes right. Ultimately evil becomes good.
We have made INCREDIBLE progress in the last year. Just a year ago, it was gonna melt by 2100. We added 200 years to the destruction of the earth. Let's party!
Monkeys flying out of their rear would be far more probable.
QUESTION FOR ALGORE: How can we handle our wobbly axis? Are wobble credits available?
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