Current Polar Sea Ice Maps 2008

Current Polar Sea Ice Maps 2008

One of my favorite sites is:

We get a map of current sea ice coverage and a second map showing the variation from the thirty year medium and is vastly more significant.

Last year we got a huge surprise when an unexpected wind system emerged and helped shift a lot of perennial ice out into the Atlantic and opened the Northwest Passage. We can reasonably conjecture that this was a release mechanism whereby surplus heat already built up in the higher latitudes as shown by unusually warm winters over the past five years, is suddenly disposed of. A result is the return this winter of rather cold conditions with plenty of snow.

After all this activity and speculation we come to the 2008 season which should help answer a few questions or prove that we are still clueless. Although we have had a very unusual winter, I see little reason to see that it was colder than the averages set before the turn of the century. That grants that the several years since have been warm and that was the source of the heat buildup that discharged last summer.

If that model holds up, then we should expect several years of heat recharge before we see another strong attack on the Artic sea ice.

This brings me to another issue. We know that the globe has been slowly warming since the onslaught of the little ice age whose cause has been attributed to the sunspot minimum and other non earthly causes. We know this because worldwide glaciers have been retreating for the past two hundred years.

The only way in which this is possible is for the atmosphere to get warmer. That does not necessarily mean hotter at surface so much as more heat is contained in the air mass itself. Presumably that also means a very slight increase in sea temperatures.

An increase in sea temperature is usually concentrated in the tropics and is discharged by increased hurricane activity. This system seems to have a thirty to forty year cycle by itself, and yes, we caught a peak with Katrina.

In the meantime the atmosphere is able to deliver extra heat onto the glaciers, or perhaps less than sufficient snow onto the glaciers. Of course it will take years to figure out which is correct. Myself, I hope enough snow landed on the Columbia snow field this winter to cause an advance.

The sea ice should breakup quickly this year and while it has the potential to be pushed back to the same line as last year, I am expecting a lot less and that a lot of this winter’s ice will get to be two year ice. We shall see.

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