The latest conspiracy theory from WUWT science deniers - losing their grip on ice

The latest conspiracy theory from science deniers at WUWT is that the National Snow and Ice Data Center (NSIDC) is up to something nefarious. (Seeing nefarious intent in the most innocuous actions is one of the hallmarks of conspiratorial thinking.)

All the fuss was about a new version of NSIDC's Sea Ice Index. It's gone from version 2 to version 3. In the latest version, monthly averages are calculated in a different way. The new version only affects monthly averages, not anything else. From the analysis report:

The Sea Ice Index has been updated to Version 3 (V3). The key update in V3 is a change in the method for calculating the numerical monthly averages of sea ice extent and sea ice area data values; that is, the data distributed in .csv and .xlsx format. This change impacts only the monthly data values in the Sea Ice Index time series and not monthly sea ice extent and concentration maps that accompany the data product, that is, the .png, .tif, and shapefile archives. Daily data are also not impacted, nor are any current conclusions drawn from the Sea Ice Index data set about the state of sea ice in either the Arctic or the Antarctic. This change is being made in response to questions raised by users of the product concerning how the monthly average ice extent and areas are calculated.

The difference between the version in calculating monthly averages is explained in the report. The previous version worked out the 15% threshold (for ice extent) for each grid cell after getting a monthly average from the daily data.  The new version works out the 15% threshold each day before averaging data.  This means that now daily data is not included for any grid cell that doesn't have 15% ice, whereas previously it may have been included. Here is how NSIDC describes it:

Monthly averages of numerical ice concentration data can be calculated through two different methods:

1. summing ice concentration data at each grid cell throughout a month, dividing by the number of days within a particular month to get average concentration for that grid cell, and then applying the 15 percent concentration threshold to the gridded field of average ice concentrations before deriving monthly area and extent, or
2. applying the 15 percent concentration threshold to the daily gridded field of concentration data before deriving that day’s area and extent; and then simply averaging those daily values over the course of the month.

The former method is the basis for the numerical algorithm in V2, while the latter describes V3.

If you're wondering how this affects the rate of change in sea ice extent in the Arctic, the report has a table for that. The only month affected to any great extent is October, when ice is rapidly forming:

Multiple conspiracy ideation criteria

Climate conspiracy blogger Anthony Watts came up with the headline: "Bad Science: NSIDC disappears Arctic sea ice extent going back years". He claimed:

From the “Arctic is screaming louder thanks to Mark Serreze and his adjustment shenanigans” department, I don’t think this is going to fly. Some of the adjustments are as much as 1.2 million square kilometers of sea ice, which is as much as some yearly variations. -Anthony

I've written previously about criteria used to identify and define conspiracy ideation. Obviously, given the "adjustment shenanigans" there are questionable motives and undoubtedly nefarious intent (criteria no. 1) because "nothing occurs by accident" (criteria no. 4). And since Anthony doesn't think "this is going to fly", he figures others will also think "something must be wrong" (criteria no. 5).  Well, it "flew" back in October last year and Version 3 of the index is still "flying", so what's the bet that Anthony's "don't think" loses out.

I don't know what he's referring to with his 1.2 million sq km. Here is Table 5 from the analysis, showing the change in climatology (1981-2010) for each month, between v2 and v3 of the sea ice index.

Maybe he was talking about the difference in the minimum for the month of October, in Table 14 of the report:

Even if he got the 1.2 million sq km from that table, I'm still puzzled by his "which is as much as some yearly variations". There is a huge monthly difference between extent in September and that in November (which straddle October, if you're wondering why I chose those months). Since 1979, the difference ranges from 3.17 to more than 6 million sq km, using the previous version, which is a lot more than Anthony's 1.2 million sq km.  There's a reason October shows the biggest change - it has the biggest change. (See below.)

Since Anthony hardly ever puts digits to keyboard these days, the rest of the article was from a denier-baiting "guest" called Tom Wiita - presumably meaning Tom works for Anthony for free (is there any other way?).

Tom was geeing up the WUWT rabble, pointing to the November NSIDC report, which reported October data, for which the change was the largest in the Arctic. Down the bottom he added this conspiratorial tidbit:

Antarctic sea ice extent is growing faster after this change. But of course, as usual, they put anti-narrative results someplace safe, like into Antarctic sea ice growth...

He implies that NSIDC should have written about Antarctic sea ice in the section on Arctic sea ice and to not do so shows nefarious intent (criteria no. 1) and "something must be wrong" (criteria no. 5). What a plonker!

The biggest difference is in October for Arctic sea ice

The months in which there is the greatest difference with the changed approach are the ones where sea ice is changing most rapidly. From the report:

There is a seasonality to V2 and V3 differences. In both the Arctic and Antarctic, the largest difference in monthly averages occur in the months when changes in the ice cover occur rapidly. In the Arctic, freeze up during the month of October is associated with the most dynamic changes in ice extent, and therefore the largest differences in V3 and V2 monthly averages. In the Antarctic, the quickly melting seasonal ice during the months of December and January is accompanied by the largest differences in V3 and V2 extent values. Overall, the southern hemisphere’s ice-ocean-atmosphere system produces a more dynamic ice edge such that V3 minus V2 differences (Figure 4) are larger than the Arctic (Figure 2) on average. 

Changes were in response to user feedback

There's one more point worth making, and that's that NSIDC made the changes in response to user feedback. After a section about how the monthly data had previously been prepared, the authors of the report wrote this (page 3):

The user community, which carefully fact-checks the monthly-average extent values presented in the popular Arctic Sea Ice News and Analysis blog against data distributed through the Sea Ice Index was not able to come up with the same values. The discrepancy stems from the different averaging methods, and user questions prompted internal discussions on how averages should be calculated. Discussions concluded with a decision to present monthly average data based on the averages of daily extent values because this method made most sense to users. 

You can see from the above para that WUWT deniers could in no way be part of the NSIDC user community. They don't "carefully fact-check" anything. They deal only in spreading disinformation. Facts are anathema to deniers.

Bringing Africa to the Arctic - the Serengeti Strategy

There's still one other point I'll make, because it's typical denier behaviour. The chorus was dogwhistled by both Anthony Watts and Tom Wiita to take a shot at Mark Serreze, who is  the Director of NSIDC.  There was only one person I saw who responded to this particular whistle (so far). Singling out one individual to bash is known as the Serengeti Strategy and is widely used at WUWT.

Dr Serreze didn't write the report, however. The authors were Ann Windnagel, Michael Brandt, Florence Fetterer and Walt Meier. Incidentally, Walt Meier has in the distant past made every effort to help Anthony and his rabble learn something about sea ice. He hasn't written for WUWT in a long time - neither has any other reputable scientist, not since Anthony Watts and his lynch mob treated Richard Betts and Tamsin Edwards so horrendously.

From the WUWT comments

Most people didn't bother reading the NSIDC analysis, they just weighed in because they want to believe that climate science is a hoax. What else could it be? After all, it's been very cold in much of the USA recently, and that proves something or the other. (Deniers would never accept that warmer waters mean heavier snowfalls, and maybe aided the meteorological "bomb", or that the changes in the Arctic could be causing the polar jet stream to meander a lot further south these days. (There are differing ideas among scientists about this - see this WaPo article by Chris Mooney. There's also a good article about recent US weather by Michael Mann.)

Source: Climate Reanalyzer

I bet many a rabid denier thinks of himself (they're predominately male) as Donald Trump just portrayed himself - as a "stable genius" (I don't think he means the horse kind), and "being, like, really smart" - oh my. The rabble at WUWT show as much decorum as the US President. Here's a sample.

Hard to tell if NME666 thinks that lying scientists earn more or less than the average liar:

January 5, 2018 at 3:02 pmthe difference between an average liar, and a lying scientist, is pay scale:-))

Tom in Florida also suggests the change in methodology means scientists are lying. I don't know if he ever learnt arithmetic.

 January 5, 2018 at 2:25 pm
As the saying goes: figures lie and liars figure.

ristvan seems to think that it was very clever of Tom Wiita to catch NSIDC red-handed secretly and nefariously discussing the change in version on the very public NSIDC website, together with a very detailed analysis. I think that falls under criteria 6, Self-Sealing Reasoning, or maybe criteria 7, Unreflexive Counterfactual Thinking. The other thing it shows is that Rudd Istvan doesn't like change (except, I guess, when it's UAH versions).

January 5, 2018 at 2:30 pm
Caught red handed again. For another example, see my guest post here 2/17/17 concerning CONUS trends and NOAA’ s shift in early 2014 to NClimDiv. Typing NClimDiv into the search bar will take you there. 

Jimmy Haigh knows for sure that 97% of the world is conspiring against him and his 3% in denial. It's humankind's biggest ever conspiracy in the whole wide world. He's as eloquent as his demi-god:

January 5, 2018 at 3:51 pm
Lying $cumb@g$. 

WR just knows that everything climate scientists do is nefarious. He wouldn't have it any other way.

January 5, 2018 at 9:56 pm
Regardless of the merits of the change in method, the fact is that if it didn’t result in lower levels of ice and an accelerated decline then the change wouldn’t have been made. They know it, and we know it, just like with the one-way temperature adjustments. These “scientists” can’t even pretend to be unbiased observers.

 References and further reading

Windnagel, A., M. Brandt, F. Fetterer, and W. Meier. 2017. Sea Ice Index Version 3 Analysis. NSIDC Special Report 19. Boulder CO, USA: National Snow and Ice Data Center. http://nsidc.org/sites/nsidc.org/files/files/NSIDC-special-report-19.pdf.

• NOAA@NSIDC Releases Sea Ice Index, Version 3.0 - article announcing the new version and the report about it - NSIDC, 20 October 2017.
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Curses! It's a conspiracy! The Fury is Back Thrice Over - HotWhopper article about deniers and their conspiracy theorising, with Stephan Lewandowsky et al (July 2015)