Pacific Spirit Marine Institute
Thursday, March 20, 2008
On March 18 NASA released a report on Arctic Sea Ice. Global Warming Nay-Sayers are spinning some facts in the report to shore up their argument that Global Warming a vast left wing conspiracy while most mainstream media have made little mention of the report.
At the heart of the study is the perennial sea ice. Perennial sea ice is “old ice”. In fact Walt Meier, National Snow and Ice Data Center calls the oldest ice “tough as nails”. Perennial ice is ice that is more than a year old.
While this March NASA’s Aqua satellite, NOAA and U.S. Defense Department satellites showed a slight increase of 3.9 percent over the previous 3 years it is still below the long-term average by 2.2 percent. The increase in the ice occurred due to surface temperatures that were colder than the historical averages.
Most troubling was the area of perennial ice has decreased to an all-time minimum.
On the heels of the ‘new ice’ comes the summer melt season. The new ice is much thinner. The thick and hardy perennial ice used to cover 50-60% of the Arctic, this year it covers less than 30%.
The ‘tough as nails’ very old ice that remains in the Arctic for at least 6 years made up 20% of the Arctic area in the mid to late 80’s. This winter the tough stuff had decreased to just a tiny 6%.
According to NASA Polar ice reflects light from the sun. As this ice begins to melt, less sunlight gets reflected back into space. The sun is instead absorbed into the oceans and land raising the overall temperature and fueling further melting. This results in a positive feedback loop called ice albedo feedback. The more the ice disappears, the more likely it is to continue to disappear.
Photo Thanks: NASA
In September 2007, the Northwest Passage was ice-free for the first time since satellite records began.
It will be interesting to see the comparison of this image with the September 2008 when it is taken.
Labels: Arctic, Global Warming, NASA, Northwest Passage, Polar Ice
© 2009, Pacific Spirit Marine Institute.
NASA Report: Arctic still on "thin ice".
