What Just Happened to the Arctic Sea Ice?

The extent of the Arctic sea ice has skyrocketed in the last few days. Take a look at these plots from the National Snow and Ice Data Center (NSIDC).


 




It was thought we had passed the maximum sea ice extent. Instead, in the space of only four days, the extent has increased by 490,000 square kilometers, not only surpassing the level that had been tagged as the maximum, but passing the maximum from last year as well. And, it appears more increase is likely.

Is this data valid or the result of some anomaly? If valid, what does this surge mean? Is there more ice or is this merely the artifact of the 15% threshold. If the ice breaks up and spreads, there is more ice extent even with less total ice. Or, has there been some kind of temperature drop resulting in the growth of ice in certain regions?

This is what the temperature across the region looked like for April 10th (the dark areas are areas with no data).

Source: Polar Portal

This is what it looked like a week ago.

Source: Polar Portal

If anything, it looks to me as if the ice is warmer now than a week ago. I see nothing that would make me expect a surge to occur.

It will be interesting to see what NSIDC says.

UPDATE:

NSIDC has stated "The daily sea ice extent images are sporadically displaying erroneous data. NSIDC is investigating with our satellite data providers." What it looks like to me is one axis has been reversed somehow. If we change the change in the y-directions (up and down on the graph) and leave the x-components the same, we would get a plot that is entirely consistent with the trendline of the previous data. We'll see how this plays out.