Monday, October 28, 2013

Denier weirdness: Bob Tisdale is "especially" stubborn in his denial

Sou | 9:44 PM Go to the first of 17 comments. Add a comment

This is a follow-on from my previous article.  It shows the extent to which some people suffer confirmation bias - and deny facts.

I've written about this disability before - here and here, which featured Bob Tisdale too.

When I read some of the comments to my last article it prompted me to go and re-read Tamino's article as well as Bob's article. Veritas6053 asked a question of another commenter and answered it:
why are you not asking Tamino the same question when he detrended the data?
it looks as though Tisdale used detrended data because Tamino used detrended data.
btw, detrending is done all of the time. NOAA's AMO index is detrended N. Atlantic SSTa data.
So I went back to Tamino's article to see why he detrended the data.  It was for the same reason as Bob gave in his article (archived here).  They both detrended the data to determine whether or not 1990 was especially hot.

Here is Tamino's chart using just GISTemp data.  He's circled 1990 in red:
Source: Tamino's Open Mind
Here is Bob's chart (updated archive here), based on an average of five data series comprising two lower troposphere and three surface temperature:

Source: Bob Tisdale at WUWT

Both charts show that 1990 lay above the trendline.  That's not exceptional of itself.  One would expect that roughly half the data points would be above the trendline.

However Bob's chart shows that 1990 was fairly hot, even after removing the trend.  In Bob's chart there were only eight years where the anomaly was higher, out of the 34 data points he showed.

Tamino's chart also shows 1990 was hot even when the trend is removed.  Tamino stated that 1990 was "10th-hottest departure from the smooth trend in the 133-year data record from NASA".

Here again is the chart I originally created when Bob first claimed that 1990 was not an especially hot year:

Data Source: NASA and WUWT!

In other words, all charts show that 1990 was a very hot year for the time.

My chart above shows that 1990 was at the time an especially hot year in absolute terms.  It was the hottest year on record at the time and the 1990 record didn't get broken for another five years.

The charts from Tamino and Bob Tisdale show that it was also an especially hot year even if the warming trend is removed - about equal 9th highest above the trend since 1979 using five data sets (Bob Tisdale) and tenth highest above the trend in 133 years of data (Tamino).

And since Bob Tisdale made much of the fact that there was no ENSO event that year, 1990 can be considered an especially hot year with no help from any El Nino.

Here is how Bob explains his stance in response to someone who pointed out the obvious - excerpt with my bold italics (archived here):
We appear to have different definitions of “especially hot”, joeldshore. Looking at my Figure 8, there are 19 years “hotter than the trendline”. The average positive deviation of those 19 years is 0.078 deg C. For 1990, the difference was 0.068 deg C. Being below the average of the years with the positive deviations, doesn’t make 1990 “especially hot” in my book. If you’re looking for an example of “especially hot”, that would be 1998. October 28, 2013 at 1:04 am
Bob notes that there were 19 years where the temperature was above his trendline.  This is roughly to be expected, given there are 34 years in his series.  Yet he is still trying to argue that despite the fact that 1990 was not just above his trendline but exceeded by only eight other data points of those 34 years, it wasn't "especially" hot.

Bob's argument is that using his averaged data it was "below the average of the years with the positive deviations".  But look at his series again.  There is one year that dragged up that average by a heap.  That was, you guessed it, 1998.  In fact, I think it would be fair to conclude that in Bob's mind, only the very hottest year was "especially hot"!  And this was eight years after 1990 so really, should it even be considered?

Now all that is leaving aside that the world is warming.  The trend matters!  It's getting hotter.  1990 was at the time the hottest year on record and retained that distinction for another five years.  I think Bob Tisdale would like to ignore the trend altogether.

I've got to say that IMO Bob's mammoth and repeated efforts to deny the fact that 1990 was hot seem pathetic, to say the least.

Additional observation: Bob's argument is not dissimilar to fake sceptics arguing that if it's happened before it's not extreme.  A record doesn't have to be broken to rate as "extreme".  All that needs to happen is for the data to be at close to the upper or lower extremities of a range.  Of course if a record is broken it would normally be considered extreme.   Like when 1990 broke all records.  It was not just especially hot, it was an extremely hot year!


  1. If I was Tisdale I guess I'd feel pretty humiliated by Tamino's systematic - and rather wittily cruel - demolition, too, and well might he be smarting to try to salvage some dignity.

    But the fact is, for the reasons meticulously spelled out originally at Tamino's site, he's W. R. O. N G.! Get it? WRONG. Piling more wrong on top just ain't gonna help.

    (I figure that means my hunch about 'stopgreensuicide' was sound. Turns out you can judge a blog by its cover...)

  2. One way to avoid being ridiculed is not to make oneself ridiculous. Tisdale doesn't seem to learning that lesson.

    His "19 years above trend" and "below the average for positive deviants" is transparent sophistry (not that the average WUWTer will see through it). On the other hand, he has inadvertantly acknowledged the trend.

    "Pathetic" is indeed the word for such juvenile defensiveness, which speaks of deep insecurity when faced with the likes of Tamino.

  3. Possibly he could be making a good point that Foster is using a dataset thats highly corrupted.

    Nothing new in that.

    1. It's like the anti-vaxxers, no matter how you slice and dice the data to answer their complaints, they continue to complain.


    2. "Possibly he good be making a good point..." , yawn, the old 'GISS-is-corrupted' zombie trolling staple. If that's your idea of a 'good point', no wonder you're nowhere.

    3. ha ha. Classic fake sceptic comment. When the data doesn't say what they want they say it's the data that's wrong. Blind to the fact that the ice is melting, the seas are rising etc etc.

      Looks as if we've been visited by a conspiracy theorist of the "it's the biggest ever hoax in history" variety.

      Does anonymous think Bob Tisdale used "corrupted data" too? Perhaps it's a case of "all the temperature data is corrupted, including that of Roy Spencer and John Christy at UAH" because it doesn't show the ice age that cometh!

  4. I've said this before, Bob's problems start from his reluctance/inability to understand oceanic warming mechanics. He'd get further if he gave up these self-humiliating graphic fumblings...or maybe he knows his audience like the wiggles better than the details.

  5. I'm sure all Australians would agree that The Wiggles is very much his audience's level... ;-)

    Apart from Andrew Bolt, of course.

  6. Sou says "It shows the extent to which some people suffer confirmation bias - and deny facts."

    The irony is delicious.

    1. Yeah yeah - all the world's Academies of Science are wrong, and Willard Anthony Watts, Lord Monckton and the Sticky Bishop are right!

  7. B-Tis does not take criticism lightly


    1. Woha, I hadn't taken a look at Curry's place for a while. It's one nutter versus another for hundreds of posts!


    2. But watch out for "A fan of more discourse" -consistently one of the funniest debunkers of denialist drivel, he/she apparently spends a lot of time trying to talk sense into the denizens and la Curry.

    3. Bob 'Drivel' Tisdale just one of those arrogant bullies of course that sort cannot stand criticism. Guess what kind of government that type would set up.

  8. Aussies: I'm popping in to point out that GetUp! fears that Shorten's about to backflip on the carbon tax.

    Completing our transition from international beacon to global laughing stock.

    Don't let him.

    Here's the link.

    (I also predict this would be a whole-party suicide note that would make Rudd's walking away from 'the moral challenge of our generation' pale into insignificance by comparison. You see, Liberal Party voters already vote for the Liberal Party, Bill, and Labor voters are just going to slink off in disgust...)

  9. 1990 had positive ONI numbers throughout. Right now that would very likely cause a warmest year.


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