Friday, December 29, 2006

Tipping Point Doom

Warming hits 'tipping point'
Siberia feels the heat It's a frozen peat bog the size of France and Germany combined, contains billions of tonnes of greenhouse gas and, for the first time since the ice age, it is melting

Ian Sample, science correspondent Thursday August 11, 2005

The Guardian

A vast expanse of western Sibera is undergoing an unprecedented thaw that could dramatically increase the rate of global warming, climate scientists warn today.
Researchers who have recently returned from the region found that an area of permafrost spanning a million square kilometres - the size of France and Germany combined - has started to melt for the first time since it formed 11,000 years ago at the end of the last ice age.

Article continues

The area, which covers the entire sub-Arctic region of western Siberia, is the world's largest frozen peat bog and scientists fear that as it thaws, it will release billions of tonnes of methane, a greenhouse gas 20 times more potent than carbon dioxide, into the atmosphere.
It is a scenario climate scientists have feared since first identifying "tipping points" - delicate thresholds where a slight rise in the Earth's temperature can cause a dramatic change in the environment that itself triggers a far greater increase in global temperatures.

The discovery was made by Sergei Kirpotin at Tomsk State University in western Siberia and Judith Marquand at Oxford University and is reported in New Scientist today...,12374,1546824,00.html

Climate warning as Siberia melts 11 August 2005 news service
Fred Pearce

Published on Thursday, September 7, 2006 by the Associated Press
Scientists Find New Global Warming 'Time Bomb’
by Seth Borenstein

WASHINGTON — Global warming gases trapped in the soil are bubbling out of the thawing permafrost in amounts far higher than previously thought and may trigger what researchers warn is a climate time bomb

...The permafrost issue has caused a quiet buzz of concern among climate scientists and geologists. Specialists in Arctic climate are coming up with research plans to study the permafrost effect, which is not well understood or observed, said Robert Corell, chairman of the Arctic Climate Impact Assessment, a study group of 300 scientists.

“It’s kind of like a slow-motion time bomb,” said Ted Schuur, a professor of ecosystem ecology at the University of Florida and co-author of the study in Science...

Most of the yedoma is in little-studied areas of northern and eastern Siberia. What makes that permafrost special is that much of it lies under lakes; the carbon below gets released as methane. Carbon beneath dry permafrost is released as carbon dioxide.

Using special underwater bubble traps, Walter and her colleagues found giant hot spots of bubbling methane that were never measured before because they were hard to reach.

“I don’t think it can be easily stopped; we’d really have to have major cooling for it to stop,” Walter said.

Scientists aren’t quite sure whether methane or carbon dioxide is worse. Methane is far more powerful in trapping heat, but only lasts about a decade before it dissipates into carbon dioxide and other chemicals. Carbon dioxide traps heat for about a century.

“The bottom line is it’s better if it stays frozen in the ground,” Schuur said. “But we’re getting to the point where it’s going more and more into the atmosphere.”

Vladimir Romanovsky, geophysics professor at the University of Alaska at Fairbanks, said he thinks the big methane or carbon dioxide release hasn’t started yet, but it’s coming. In Alaska and Canada — which have far less permafrost than Siberia — it’s closer to happening, he said. Already, the Alaskan permafrost is reaching the thawing point in many areas.

17 May 2006
El Niño and Global Warming
Filed under: Climate Science Oceans— group @ 9:49 am
By Rasmus Benestad & Raymond Pierrehumbert

This is the first part of a planned mini-series of 3 posts on tropical climate, circulation, and oceanic response in conjunction with a global warming. Climate change related to a global warming is more than just temperature and precipitation -massive atmospheric circulations change too, and these changes can have consequences

Well, not to sound too catty, but I have to admit, I got a kick out of two suggestions of AGW causes in the questions in the Q & A in the Seattle times: (1) the effects of heat from cigarette smoke, and (2) the effect of human body heat!

Do you mean to say you guys haven't included these important "forcings" in your models? In that case, you can count me as a skeptic!

Also, what about the WV effect of increased Chai consumption?

Comment by dan allan — 17 Oct 2005 @ 4:31 pm

29. The following is part of an article that was printed last year ---
{Vintage Wine Records Trace Climate Change to 1300s
John Roach
for National Geographic News
November 17, 2004

Connoisseurs may pore over grape-harvest records in search of the perfect vintage of wine. But a team of French scientists and historians is toasting the same records for the insights they yield on past climate...

120. How about this statement I just recevied denying global warming:

"As to the global warming issue, the argument is so full of hype and scare tactics that I for one have decided that it is a political argument and not a scientific argument at all. In fact, while there is some evidence of a shrinking arctic ice cap in the Beaufort sea areas over the last decade, there is growth in the iceland glacier one of the largest in the world, there is growth in the section of ice due north of Canada (a map that Mark York put up) and there is a significant amount of research that shows that the antarctic ice cap is growing fairly rapidly while the Ross Ice shelf is shrinking."..

Mark York?

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