Sunday :: Mar 29, 2009

Latest News From Arctic Shows Region Warming Much Faster Than Predicted


by Mary

The IPCC published their report in 2007. Since then, climate scientists have been gathering and analyzing the new data that has been coming from sensors that have been placed around the world. And as Christina wrote earlier this month, new data is changing the understanding and climate models for the great ice sheets and the sea ice.

Well, new information from the Arctic shows that it is warming much faster than the rest of the planet and the implications are very worrying. This new data shows that the IPCC report underestimated the feedback effects that are now visibly operating in the far north.

What is certain is that the Arctic is warming faster than any other place on Earth. While the average global temperature has risen by less than 1 °C over the past three decades, there has been warming over much of the Arctic Ocean of around 3 °C. In some areas where the ice has been lost, temperatures have risen by 5 °C.

This intense warming is not confined to the Arctic Ocean. It extends south, deep into the land masses of Siberia, Alaska, Canada, Greenland and Scandinavia, and to their snowfields, ice sheets and permafrost. In 2007, the North American Arctic was more than 2 °C warmer than the average for 1951 to 1980, and parts of Siberia over 3 °C warmer. In 2008, most of Siberia was 2 °C warmer than average (see map).

The reason this is ominous is because of the vast quantity of sequestered carbon that is trapped in the permafrost and frozen lakes which as they melt release methane gas. Methane is a much worse greenhouse gas than carbon dioxide and if too much of it is released too fast, nothing we do can mitigate the damage.

No one knows for sure how much carbon is locked away in permafrost, but it seems there is much more than we thought. An international study headed by Edward Schuur of the University of Florida last year doubled previous estimates of the carbon content of permafrost to about 1600 billion tonnes - roughly a third of all the carbon in the world's soils and twice as much as is in the atmosphere.

Schuur estimates that 100 billion tonnes of this carbon could be released by thawing this century, based on standard scenarios. If that all emerged in the form of methane, it would have a warming effect equivalent to 270 years of carbon dioxide emissions at current levels. "It's a kind of slow-motion time bomb," he says.

So how worried should we be? According to the researchers who are seeing the changes in real time, pretty darn worried.

Most worrying of all is the risk of a runaway greenhouse effect. The carbon stored in the far north has the potential to raise global temperatures by 10 °C or more. If global warming leads to the release of more greenhouse gases, these releases will cause yet more warming and still more carbon will escape to the atmosphere. Eventually the feedback process would continue even if we cut our greenhouse emissions to zero. At that point climate change would be out of control.

So although, we are currently focused on our immediate human crises (wars, economy, etc), that is no excuse for not addressing this problem right now. After all, a mere 6 °C guarantees an end of life as we know it on earth.

Mary :: 6:35 PM :: Comments (9) :: Digg It!