March 9, 2005

Arctic Ice Pack melting

There was a big outcry over the discovery that parts of the Arctic Ice Pack were receding. The environmentalists used this opportunity to shove yet another righteous sermon about "Global Warming" down the throats of the unbelievers. Only it turns out that the Arctic Ice Pack has been going through regular cycles of advancing and receding -- from The Scotsman:
Polar history shows melting ice-cap may be a natural cycle
The melting of sea ice at the North Pole may be the result of a centuries-old natural cycle and not an indicator of man-made global warming, Scottish scientists have found.

After researching the log-books of Arctic explorers spanning the past 300 years, scientists believe that the outer edge of sea ice may expand and contract over regular periods of 60 to 80 years. This change corresponds roughly with known cyclical changes in atmospheric temperature.

The finding opens the possibility that the recent worrying changes in Arctic sea ice are simply the result of standard cyclical movements, and not a harbinger of major climate change.
And some verification from real-world data?
The amount of sea ice is currently near its lowest point in the cycle and should begin to increase within about five years.

As a result, Dr Chad Dick, a Scottish scientist working at the Norwegian Polar Institute in Tromso, believes the next five to ten years will be a critical period in our understanding of sea ice and the impact, if any, of long-term global warming.

Concern has been expressed recently that animals such as polar bears could become extinct because sea ice is disappearing. The new research by Dr Dick and a colleague, Dr Dimitry Divine, gives rise to hopes the melting will stop soon.
It will be interesting to follow this. There are many periodic cycles operating here, the major cooling and warming one that seems to take about 400 years, this 60 to 80 year Polar cycle. And of course, no one talks about the elephant in the living room -- the major contribution to warming and the biggest (in terms of actual change) greenhouse gas is water vapor. Nobody can do anything about this so it's just swept under the rug... Posted by DaveH at March 9, 2005 2:13 PM