There's no reason to believe that the earth will somehow spontaneously begin compensating for the greenhouse gasses we are adding. I agree that modest warming is not necessarily bad, but we dont know yet precisely how much we are contributing, (could be less, could be more...) and the most dangerous part is that there are certain "tipping points", where the process can accelerate itself.
From the Guardian , 11 August 2005.
Researchers who have recently returned from the region found that an area of permafrost spanning a million square kilometers - 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.
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.
The researchers found that what was until recently a barren expanse of frozen peat is turning into a broken landscape of mud and lakes, some more than a kilometer across.
Dr Kirpotin told the magazine the situation was an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming". He added that the thaw had probably begun in the past three or four years.
Climate scientists yesterday reacted with alarm to the finding, and warned that predictions of future global temperatures would have to be revised upwards.
"When you start messing around with these natural systems, you can end up in situations where it's unstoppable. There are no brakes you can apply," said David Viner, a senior scientist at the Climatic Research Unit at the University of East Anglia.
"This is a big deal because you can't put the permafrost back once it's gone. The causal effect is human activity and it will ramp up temperatures even more than our emissions are doing."
Here's the complete article http://www.commondreams.org/headlines05/0811-03.htm
Basically the thawing of permafrost begins a POSITIVE Feedback Loop. Thats the opposite of a Negative feedback loop, (Like your HPTA). The warmer it gets the more methane is released, which causes further warming, further thawing, and even more methane. In short, Its a vicious cycle.
We just dont know what will happen if we keep doing this. In the abscence of definitive proof, it is wise to err on the side of caution.
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Originally Posted by TexSavant
