Thursday, September 07, 2006

Melting Permafrost Alarms Climate Scientists

The Herald
September 7, 2006

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

Methane - a greenhouse gas 23 times more powerful than carbon dioxide - is being released from permafrost at a rate five times faster than thought, according to a study being published today in the journal Nature. The findings are based on new, more accurate measuring techniques.

"The effects can be huge," said lead author Katey Walter of the University of Alaska at Fairbanks. "It's coming out a lot and there's a lot more to come out."

Scientists worry about a vicious global warming cycle that was not part of their already-gloomy climate forecast: Warming already under way thaws permafrost, soil that has been frozen for thousands of years. Thawed permafrost releases methane and carbon dioxide. Those gases reach the atmosphere and help trap heat on Earth. The trapped heat thaws more permafrost, and the cycle continues.

Some scientists say the cycle is already under way, but others disagree.

Most of the methane-releasing permafrost is in Siberia. Another study earlier this summer in the journal Science found that the amount of carbon trapped in this type of permafrost - called yedoma - may be 100 times the amount of carbon released into the air each year by the burning of fossil fuels.

It won't all come out at once or even over several decades, but if temperatures increase, then the methane and carbon dioxide will escape the soil, scientists say.

The permafrost issue has caused a quiet buzz of concern among climate scientists and geologists. Specialists on the 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.


tonyon said...

a SOLAR ENERGY CAR made by amateurs have crossed Australia. Why CAR´S FACTORIES do not want to know that?. Petroleum´s economic interests. Shame politicians

tonyon said... warming ("good" no longer spend cold)... pouring pollutants greenhouse effect into the air is melting the Poles. Besides on melting permafrost will free into the Atmosphere million Tm of methane with big greenhouse effect. This large amount of freshwater to the ocean could stop deep sea currents which depend on starting downwards on a delicate balance between fresh and salty water and temperatures. Heat from the Sun reaches the equator and currents distribute it throughout the Planet, then...goodbye to our warm climate. The horizontal oceanic currents produced by winds and some other by the rotation of the Earth, rotating all by the Coriolis effect, will continue...but the vertical currents produced by the sinking of horizontal currents of dense salty water that reaches the Poles where the Water is sweeter, less salty, and form deep currents would stop (why are the Grand Banks fishing in cold latitudes?...because over there is the POLAR ICE, freshwater, different sweet/salty density, salty dense water arriving and sinks in a little salty water environment...nutrients that are removed from the bottom and rise to the surface, phytoplankton that feed on nutrients, zooplankton that feed on phytoplankton, fish that feed on zooplankton)... No polar ice over there will be no vertical currents...could reduce the rise of nutrients to the surface and therefore PHYTOPLANKTON SHORTAGE MAY DECREASING ITS VITAL CONTRIBUTION WITH OXYGEN TO THE ATMOSPHERE (90 %) in some places of more warm latitudes carry out the surface hot water permitting the outcropping to surface of water and plankton (the upwelling) from the bottom cold current coming from the Pole, forming other Banks fishing... Without polar ice the sea it could almost stratified into horizontal layers with little energetic movement of water masses in vertical which is what removes fertilizer nutrients from the sea bottom... Besides lowering salinity of the sea, for that contribution with freshwater to melt the Poles, will increase evaporation (ebullioscopy: the less salt has, more evaporates) producing gigantic storm clouds as have never seen, that together with altering of the ocean currents, could cool areas of the Planet causing a new ice age... Warming...invasion of tropical diseases carried by their transfer agents, already without the "general winter" containing them would fall upon the World like a plague...can produce a cooling, a new ice age, like living at the North Pole...and less oxygen in the Atmosphere... Is not known to be worse... Go choosing.