The Polar Science Center has released some extra PIOMAS gridded data that allows smart bunnies like Wipneus and Chris Reynolds to show how ice thickness is distributed around the Arctic. Here's a thickness distribution map made by Wipneus that shows the difference between March 2012 and March this year:
It seems the situation has basically flip-flopped, with thicker ice now off the Siberian coast and thinner ice in the Beaufort and Chukchi Seas. This is most probably due to those big highs that caused a very strong Beaufort Gyre that pulled at the ice pack so hard it cracked all over the Beaufort Sea and beyond, but at the same time made the ice compact against the Siberian coast. This thicker ice along the Siberian coast is at a relatively low latitude and is bound to melt away anyhow, although it will be interesting to see when the Northern Sea Route opens this year.
Last year I was expecting thicker ice in the Beaufort and Chukchi Seas to protect the centre of the ice pack like had happened in 2010 and 2011, but I was completely wrong on that. The ice just disappeared at a rapid pace, an amazing sight. If the above map is correct we don't even have thick ice there now, and so I'm with Chris Reynolds when he says: "I expect an aggressive melt from the first week of June onwards, when the melt really starts within the Arctic Ocean."
Speaking of which: Chris has produced this thickness distribution map for March 2013, with next to that a table that shows the division between ice that is thinner than 2 metres and ice that is thicker than 2 metres since 1978:
According to the PIOMAS model there's even less thick ice than in the previous two years, which makes sense, of course, after last year's record smasher. There's now more first-year ice than there has ever been since the record started. Some real weird weather is needed to prevent this coming melting season from becoming a serious pretender to the throne.
To top this update off I present to you Andy Lee Robinson's latest PIOMAS vid: