It is important to get this right. There is something interesting happening in the Arctic right now, and some people are pointing to it and jumping up and down and yelling about how it is a major climate change event. But it may very well not be. Or it could be. The thing that is happening is something that normally happens, but there are features of the event that are odd. We won't know its significance until the Northern Summer, and even then we won't be sure if this is just an unusual thing for this year or a new trend because, by definition, trends run over periods of time.
Every year as you know a certain amount of Arctic Sea ice melts away, and part of that melting process involves the ice breaking into separate chunks and floating around in a big gyre. If you live on or visit a lake in the frozen regions of North America, during the spring, you've probably observed the phenomenon. Well, this happens Big Time in the Arctic.
Ice is still forming in some regions of the Arctic, and may continue to form and thicken for some time to come, though the average effect at the moment is melting (see below). But for some reason a large region of ice has started to break up and float around loose, earlier than expected.
One possible outcome of this would be the more rapid melting of ice in that region once extensive melting starts, because broken up ice melts faster than continuous solid ice. Another possible outcome is that it all refreezes in place and has very little effect on what happens in the coming Northern Summer.
From the Arctic Sea Ice Blog:
It is normal for the ice to crack and for leads to occur. However, this is very extensive cracking and there are some very big leads, and all of it seems to come earlier than expected. Given last year's melting mayhem and the low amount of multi-year ice, it makes one wonder whether this early cracking will have any effect in the melting season to come.... Maybe this will have zero influence. We don't know. That's why we watch.
So, how is the march of melt going in the Arctic, independently of this breaking up event? Here is a graph from the National Snow and Ice Data Center, which is quickly becoming a very important source of critical information, showing the current state of Arctic Ice in relation to expectations:
Robert Scribbler, in a recent blog post, is predicting rapid and extensive melting. He cites as important factors "...cracking, rapid ice movement, thin ice, warmer than average air temps, and negative Arctic Oscillation..." and describes each of these factors.
- Detailed discussion by Nev\en Acropolis as a guest blogger on Climate Progress: Ice Breaking News: This Is Your 2013 Arctic Freezing Season On Crack
- Possible Mechanism for the current state of the arctic: The Winter The Polar Vortex Collapsed.
Sitting here in late March in a Minnesota covered with a thick blanket of snow and above-freezing daily temperatures happing over the coming week for the first time in months (still no overnight thaws) it is hard to imagine the Arctic as being warm, but if you think about it a bit it makes sense. The Arctic, the Subarctic and the northern Temperate region are simply sharing their air masses in a different way than they usually do. It is a bit like someone drilled a big hole in the bottom of the freezer, connecting it to the refrigerator below. Down here in the fridge (Minnesota) the milk is freezing, but up there in the freezer, the ice is wet and sloppy.
I wonder how long it will be before cruise ships start to regularly ply the Arctic Sea for recreational purposes?
Just to add --
The break-up currently extends from Alaska to the Fram Straight. An event that takes up almost half the sea-ice and nearly all the remaining thick ice.
Also, I want to qualify by stating that it is much more likely rapid melt will occur under current conditions. Weather and temperature used to rule the Arctic melt season. A new factor-- thin ice -- is making the environment more volatile and making rapid melt more likely.
All that said, if we have a long period of weather similar to 2007 (what appears to be happening now), then this melt season could be devastating.
If it's a one-year occurrence, then it's a blip on the radar, no big deal.
If it's a long-term trend? It's...it's pretty scary, as an accelerating factor, honestly.
The Arctic sea ice "cracking thing" continues apace. Here's the latest satellite images and photos taken from a low flying NASA P3-B "airborne laboratory" which is currently taking a close look at the sorry state of the sea ice on their latest "IceBridge" mission.