Watching Sea Ice disappear

Last week we listened to press stories pointing out that the sea ice was already at its lowest level ever recorded. And the season had a few weeks yet to run.

I just looked at the next snapshot from august 22 and am even more startled. Appreciate that I have been looking at these maps now for several years and am fairly comfortable in interpreting them.

Over a one week period, the apparent boundaries retreated about 10 to 20 percent and we also have a large expansion of grey tones within the ice floe. This means that the amount of open water within the floe expanded hugely. This ice is still melting fast.

In fact, this is more noteworthy than the reduction of the boundaries which has been clipping along for the past several weeks. The thinning of the ice floe was masked up to now by the fact of its original thickness. For it to grey up so swiftly tells us that weeks of melting are having its effect and that much of the remaining ice is very close to disappearing. In other words, by the time you have extensive open water it is close to been over.

Go to: for the current cover and then go back one week to compare.

If we were looking at a glacier, we would be describing this as galloping. I suspect that we are looking almost at the end of the melt for this season, but the movement just in one week is huge and one can readily see that another six weeks at this rate would wipe out the polar sea ice in its entirety. These are pictures that do not lie.

It has been stated that three principle melts will clean out the ice. We had number one in 1998 with no recovery in the intervening years. This year we are having number 2. After this year, I suspect that there will be almost no multiyear ice left of consequence, setting the stage for a number 3 melt to come along in the next decade.

It is noteworthy, that however the amount of ice is reduced, that the sea ice continues to span the Arctic cutting of shipping from using the over the pole route through Russian waters. In a way it is a natural fluke that this is so. Even it the arctic warmed up enough to ensure a clearing of the ice every year, it appears that a northern route will continue to be impractical or at least a daring gamble at best.

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