Thursday, September 18, 2008

Final Sea Ice

Needless to say, I am no longer alone in recognizing that the perennial sea ice will be gone in five years. When I posted the aggressive 2012 prediction late last summer, the consensus was many decades. This item shows that most are now bowing to the inevitable. The areal extent was slightly larger than last year, but the unusual winds of 2007 did not come along and perhaps compress it more.

We have no way of knowing for sure, but I expect that this year’s actual ice loss was significant though not as large as last years. It is still a loss rather than a gain and what is now obvious to everyone is that we are observing the dissolution of the perennial Arctic sea ice. As I posted in the past, the average loss per year is linear inasmuch as roughly the same value M will be extracted from the total. But now the exposed area of the Arctic is increasing sharply, the value of M can even be expected to modestly increase as more solar energy is absorbed.

All this adds up to an accelerating collapse of the ice over the next four years. I have yet to see a reason to back of my 2012 prediction. It is necessary to have a much colder and much longer winter than last year’s.

As I pointed out to my readers last year, this decline is all about the effect of a small incremental increase M in available heat to the Arctic. As the total ice mass declines, the effect of m steadily increases, until it becomes the dominant factor when there is little of the original ice left. We are obviously there and it can only get worse now until the long term ice is all gone over the next four years or so.

This summer, the melting and warming of the ice mass continued. Major parts of the super thick floating ice sheets broke free confirming the ongoing weakening and warming of even this ice. And this item reports that new ice that is visible is weak and thin.

I would like to believe that the apparent slight reduction in solar energy is sufficient to induce a cooling of the Northern Hemisphere. Right now the evidence is pretty sketchy and not obvious, reports to the contrary.

We have also just had a lively hurricane season which shows that the equatorial heat engine is not shut down and is winding up again. Maybe with this blow out, we will now get a couple of quiet years.

Last year proved that none of this helped in predicting the upcoming winter. However a mild winter seems to presage a warm summer in the Arctic.

Arctic Sea Ice Season Underscores Accelerating Decline
Written by Dana Nuccitelli

Published on September 17th, 2008

Posted in Environmental & Climate Science

According to the National Snow and Ice Data Center (NSIDC), Arctic sea ice cover appears to have reached its minimum extent for the year, the second-lowest extent recorded since the dawn of the satellite era.

While above the record minimum Arctic sea ice extent set on September 16, 2007, this year further reinforces the strong negative trend in summertime ice extent observed over the past thirty years.

Despite overall cooler summer temperatures, the 2008 minimum extent is only 390,000 square kilometers (150,000 square miles), or 9.4%, more than the record-setting 2007 minimum. The 2008 minimum extent is 15.0% less than the next-lowest minimum extent set in 2005 and 33.1% less than the average minimum extent from 1979 to 2000.

This season further reinforces the long-term downward trend of sea ice extent.

Even though the sea ice didn’t retreat this year as much as last summer, “there was no real sign of recovery,” said Walt Meier of NSIDC. This year was cooler and other weather conditions weren’t as bad, he said.

“We’re kind of in a new state of the Arctic basically, and it’s not a good one,” Meier said. “We’re definitely sliding towards a point where the summer sea ice will be gone.”

Scientists have predicted that the Arctic will become ice free in the summer by the year 2013, if not sooner. This also does not bode well for global warming, since ice reflects sunlight whereas dark oceans absorb it.

On top of that, the Arctic ice melting trend has shifted. Normally the ice would reach its minimum extent by early September, but after the record melt of 2007, much of the ice reformed with much less thickness, allowing it to continue to melt through mid-September this year.

The Arctic is warming at a faster rate than the rest of the planet, and can be considered a ‘canary in the coal mine’. Right now, that canary is not in good health.

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