It's been a week since I announced that the ice in the Beaufort Sea was going to come under early pressure. Here's a quick update on what has happened so far, how the forecast played out, and what the short-term conditions for this part of the Arctic will be.
As expected, the Beaufort Gyre kicked into action, big time, with winds causing large cracks in the ice pack, moving it westwards and away from the Alaskan and Canadian coasts. The massive polynyas that are left behind, get partially covered with a thin veneer of ice.
Here's an animation showing the difference between LANCE-MODIS satellite images on the first of the month and two weeks later:
Quite impressive, isn't it? As if someone threw a giant brick into it.
Here's an animation showing all days between April 1st and 14th (the file is somewhat large, apologies if it loads slowly):
Over the course of just two weeks, those huge ice floes are being transported hundreds of miles. Also notice how towards the end of the animation another huge part of the ice pack, north of the Canadian Arctic Archipelago is pulled into the Gyre. This is mostly multi-year ice, as can be seen on the most recent Tschudi/Maslanik/Fowler ice age distribution map (from the latest NSIDC monthly analysis), which I've combined with the latest satellite image:
A lot of 4- and 5-year old ice that is being transported to a place where it can either protect the inner core from melting towards the end of the melting season (like happened in 2010 and 2011), or melt out completely.
Here's a video made by Jim Hunt from The Great White Con blog showing the movement since February 1st (including the first cracking event):
As I wrote last week:
It will be interesting to see whether that high pressure area will cause an early decline, earlier than last year.
And it has. Not just in the Beaufort Sea, but in the Chukchi Sea as well.
Here are the regional sea ice area graphs as provided by Wipneus
on Arctische Pinguin:
And here's a close-up only showing the last three years, also from Arctische Pinguin (via Great White Con):
Something else I wrote last week:
The first thing to notice when focusing on the [temperature forecast], is the green colour that spreads over Alaska, which indicates above freezing conditions. This will most probably impact snow cover not too far from the coast, and as said, no snow cover means increasingly warmer temperatures that can be blown towards the Beaufort Sea at some point.
As shown on this map provided by the US National Ice Center, there are already some patches of snowless ground cover in Alaska, and these are bound to get larger in the coming week.
Here's an animation showing the northward progression of the snow cover edge in the past week (images provided by said US NIC):
Those patches did get larger, but not so large that it will impact temperatures near and in the Beaufort Sea. For the time being.
Now, if this were the end of it, it would have been a notable event, with lots of movement, cracking and pulling multi-year ice into zones where there's a risk of it melting out completely during the summer, and that's it.
But the funny thing is: it's not over yet. Usually it's the cyclones that are persistent, as we saw in 2013, but this time a high-pressure area, or anti-cyclone, is showing little sign of giving up the ghost:
Values of 1030-1035 hPa, with peaks of up to 1040 hPa. That's high. And so many days in a row. That ice is going to move away from the coast some more. And I haven't got started on the things happening on the Atlantic side of the Arctic, export through Fram Strait and all that.
We still don't know what the overall effect of this event will be when the melting season gets going for real. Heat is lost through all that open water, but that's easily made up for once temps go up and solar radiation starts heating up the water. Hopefully, we don't see a repeat in June or July, because by then we can be fairly certain what the effect will be: Total loss.
The Pacific side of the Arctic is going to need a lot of cold and cloudy weather this summer.