Look out, Santa! According to some reports, Good St. Nick not only has to worry about delivering a few billion gifts, but the North Pole may melt out from under his feet!
How accurate is that warning?
According to the National Snow and Ice Data Center in Boulder, Colorado, the Arctic ice pack has been melting rapidly this year and is now 919,000 square miles below the thirty-year average minimum.
It is currently at the second lowest extent ever measured. (The records only extend back to 1979.)
Melting Arctic Ice, – This is a much lower amount of ice than there used to be before 2000.
Does this mean that Santa and the elves will join the polar bears floating on dwindling icebergs?
Actually, this ice melt is due to several factors, some of which are natural. Two long-term ocean cycles, the AMO (Atlantic Multidecadal Oscillation) and PDO (Pacific Decadal Oscillation), have been shifting more warm water north for several years. Some of these warmer waters are leaking into the Arctic Ocean, causing the sea ice to melt.
At the same time, a climate cycle, called the Arctic Oscillation, has weakened the winds circling the North Pole. This is allowing polar winds to plunge further south. Remember last winter and all that cold air? What is happening is that the cold air is less concentrated in the north and making the weather colder in the middle latitudes. The winds are affecting the surface waters of the Arctic Ocean and blowing more icebergs south into warmer, melting waters.
The Positive (top) and Negative (bottom) Arctic Oscillation. The negative AO lets Arctic air escape south. It has been more negative over the last few years, letting cold air and sea ice plunge south.
The negative AO causes colder weather in the Eastern US and warmer conditions in the Arctic. We had very negative AO conditions over the last two chilly winters.
History shows that these cycles in the Arctic come and go. The 1980s saw a lot of cold Arctic ice build-up. The current decade is seeing more melting.