This blog is mostly aimed at a source of criticism and fact checking for the blog 'real science' run by someone who goes by the name Steven Goddard. It is intended that material presented here is informative, neutral, impersonal and well sourced such that any of my claims can be checked and criticized in their own right if necessary.

Sunday, 1 September 2013

NSDIC wrong about low concentration ice?

The post revolves around the nsdic commenting on the low concentration ice near the north pole.
Steven cites the Arctic Sea-Ice Monitor with an image from the 31st of August saying that the low concentration ice has dissapeared, and that the nsdic had to be quick about its report on the 19th as the low conc ice was gone within a week.

The first and most obvious point, is that the 31st of August is not a week later. This is the state of the sea ice on the 26th of August:


Despite some increases the concentration is still relativly low. The university of bremen provides a more contrastful colour code using the same AMSR2 data. This is the comparative image for the 26th August.

There are still noticable areas in the atlantic secter with less than 50% concentration. (source: And note that the NSDIC actually defined low concentration ice as 20-80%.

But yes, the concentration in that part of the arctic has increased now, as Stevens image for the 31st of August shows. Given that we are at the end of the melt season this should not be too suprising. But would you have the nsdic not commenting on this? A large part of the arctic had low concentrations of ice at the time of the press release, this is a not trivial observation that deserves a paragraph devoted to it. Indeed, to not mention it would seem rather odd given how prominant it was. Read the nsdics article for yourself and decide whether or not the paragraph was written with the intention of writing something negative about the arctic: To me the post comes across as factual, unbiased and informative. There has been alot of speculation about the cyclonic nature of this summer influencing the sea ice, and I'm glad the nsdic touched upon it. Incidently steven, you did not mention the favourible comparision they made with 2012 e.g "Retreat rates increased slightly in the western Beaufort Sea and Chukchi Sea, but ice cover remains extensive in those regions compared to 2012. ". Of course if you only pick out the parts of the report that look negative, of course it is going to seem like it is enphasising the negative points.

Finally in view of a couple of the comments written on his post, particularly this one:

"I guess they do not understand regional averages. Some parts of the region will be above average and some will be below average. NSIDC has to rush these press releases to justify their existence. They are wasting our money."

Well, clearly nsdic do understand regional averages, evidenced by their breakdown at the beginning of the arcticle. However it seems only fitting to make the point in the manner steven often does. an IJIS sea ice mointer overlay map. But instead of comparing it to the lowest year on record (2012) and attempting to come up with a percentage increase (see stereographic projection errors). I will just add all the 80s, 90s and 00s averages


The pale yellow is 80s average, Darker is 90s and the dark orange is 00s average.  I think its fair to say, by most measures most places are below average. Incidently while nsdic can hardly be accused of cherry picking the negative, picking data to make it look as positive as possible is just as bad.

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