Friday, 24 July 2015

A Correction

In mid June I posted a blog post asking about whether we were facing a crash this year. This was based on the US Navy's ACNFS Model, which I have previously called HYCOM. Shortly after the post the model version I had used was put behind a password wall, the US Navy had realised that it wasn't signed off for public release.

Now it seems there is a problem with ACNFS, as found out by Peter Ellis at the Sea Ice Forum. Basically the massive melt ACNFS showed this summer was due to a glitch in the model. These things happen, the only people who don't make mistakes are those who never try anything, and the more complex one's endeavour the more likely mistakes are.

So my question in mid June about us facing a crash this year was based on flawed data.

This doesn't affect any of my recent blog posts because the password walling of ACNFS made me suspect something was up, on that I was wrong in the end, it was walled for another reason. But after the PIOMAS data I suspected something was off with ACNFS, by my June Status post I used ACNFS but came to the conclusion there would not be a crash this year.

I will be using ACNFS for ice movement, but for other metrics will probably rest use of it for the remainder of the summer season, perhaps longer, to give them time to get things sorted.

Thursday, 23 July 2015

Mid Summer 2015 Status

Taking the Arctic Ocean summer season as June to the sea ice minimum, around now is the middle of the summer. In this post I look at the state of the ice mid summer, and offer a guess of what the minimum will be.


Sunday, 19 July 2015

Hello Dipole My Old Friend

I have previously written about the Arctic Dipole, and note that it now has a Wikipedia page. Over the last two years it has been largely absent, leading myself and others to ponder whether it was a transitory phase over the 2007 to 2012 period.

It doesn't seem to have been transitory, it has dominated July so far and looks set to continue throughout the rest of July. My expectation is for it to continue into August, that however is just an expectation based on behaviour in 2007 to 2012.

Saturday, 18 July 2015

What would it take to get to 1 million kmsq?

I now have data to 15 July for regional extent (thanks Wipneus). With two months to go to the middle of September, the period for which the minimum can reasonably be expected, what would it take to reach 1 million kmsq by this September?


Saturday, 11 July 2015

The Chukchi Rout

In my previous post I covered, amongst other issues, the large region of collapsing ice shown in the Chukchi Sea. Now with three days more data it is clear that Chukchi is suffering a rout.

Tuesday, 7 July 2015

HRPT Satellite 7 July 2015

I had to post the following image because with clear skies it really paints the picture of ice state in the Pacific sector of the Arctic Ocean. Ice state is excellent for significant losses this year, a re-run of 2013 and 2014 looks very unlikely.

Friday, 3 July 2015

June 2015 Status

June data is now fully available, so here is my commentary on the current sea ice state and the month just passed. Sorry but this is a long post...