The recent demise in the Arctic sea ice extent reminds me of a story that went around about the death of Mark Twain, which he refuted by saying “The reports of my death are greatly exaggerated”. It didn’t look good in September and October as the graph of the sea ice extent showed how slow the Arctic was creating new sea ice. So I decided to look at the figures from the NSIDC in a bit of a new way. The graph above shows daily anomalies, that is the value on the day, divided by the 1988-2016 long-term average [LTA] for that day of the year, multiplied by a 100 to get a percentage. The graph as you can see had two distinct dips, one in early September just after that early minimum when the anomaly was around 65% of the LTA. The sea ice bounced back very quickly from that minimum and before the end of October was above 76% of the LTA. Those gains were quickly lost though, and by the middle of October the values had dropped to less than 68%. But interestingly, in fits and starts, the sea ice extent has bounced back and is now above the 85% mark. If you look back at summer 2012 just before the summer minimum things were a lot worst than in September with the LTA less than 55% of the LTA for a few days. Here’s a bit more of a close-up of the last few months.
This method of graphing daily anomalies is very sensitive to any daily changes in the sea ice extent, and I think it’s one of the best ways of keeping an eye on sea ice extent levels both in the Arctic, and the Antarctic, and talking of the Antarctic, here are the latest daily anomalies south of the equator.
The above graph shows very nicely the rise and fall of Antarctic sea ice in recent years. If you remember up until early 2015 Antarctic sea ice had gained a lot of new sea ice. In fact the 2014 season set a new maximum extent of over 20 million square kilometres, but since then things have been going down hill, and since early October of 2016 the sea ice anomalies have been tumbling. At the moment (3 December 2016) the anomaly stands at 84% of the LTA for that day, not a record low by any means, but certainly this season’s melt looks very aggressive, and these daily anomalies are the lowest since early 2011.
Sea ice extent is certainly in crisis, in both the Arctic and the Antarctic, but at least in the Arctic the season seems to be finally getting itself into gear a little.
The media seemed to have now picked up on this autumn’s shenanigans going on in the Arctic, a little bit late, but never mind.
- John Hammond has done a short bit of video for BBC news about it.
- And the good old Met Office, not to be outdone, an expert there blogged about the unusually warm Arctic.
Here is a list of recent articles that I’ve written on the subject, and I think it’s fairly evident that I have a bit of a thing for sea ice.
- Tropical Arctic (27 Nov)
- Polar sea ice entering unchartered waters (19 Nov)
- Sluggish ice growth in the Arctic – you bet! (3 Nov)
- Older sea ice disappearing video (29 Oct)
- Latest sea ice figures (28 Oct)
- Latest Arctic sea ice extents look dire (10 Oct)
- Fourth shortest melt season in Arctic (25 Sep)
- Second lowest Arctic sea ice minimum (Sep 16)
- Polar sea ice extremes (Sep 9)
So you can see when I add a comment to the Met Office blog, and 10 days later it’s still sat there “awaiting moderation”, I do get a bit irked. I’m not sure what’s particularly wrong with it, there are no swear words or personal insults, just a few comments about the slightly arrogant tone of the piece, and how slow off the mark they’ve been (in my opinion). So here is what I said and you can be the judge, because after 10 days I think they binned them – so much for democracy!