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Excuses Excuses! Neville Nicholls and the Stevenson screens that didn’t exist or did and were “cracked”?

Neville Nicholls and Sophie Lewis are striking back at George Christensen, MP, who accused the BOM of “wiping” the official records of heat waves in 1896 and demanded an inquiry. For some reason, despite their world class work, Nicholls and Lewis still don’t seem keen on having an inquiry — so they go to some length to explain why it’s “false” to say it was hotter in 1896 than it was in 2013. Oddly though, to come to this conclusion they don’t use BOM work, because the BOM concluded “it would be very difficult to compare the 19th-century temperature data with modern observations.” Instead that difficult task was done by Berkley. Nichols calls it “brave”, but a “fact” at the same time.

In their long article, what they don’t explain is why they almost never mention any of the hundreds of ultra hot historic temperatures in their press releases and national news. George was “wrong”, and that’s a “fact” we’re told, but most of their article  on The Conversation explains why we don’t know what the temperature was in 1896. Try not to get confused.

That old data is dodgy see — I’ll paraphrase:

  1. Satellites agree with the BOM.  (Seriously, this is their first point). Apparently Nichols and Lewis expect that the gloss of this fabulous scientific achievement, which occurs after 1979, will glow all the way back to 1896. It rather ignores the fact that the biggest BOM adjustments occur to the oldest records. (I marvel that the BOM has discovered UAH and RSS.  When those same satellites didn’t agree with the BOM’s “hottest” ever records, no one at the BOM seemed to know they existed.)
  2. Not all thermometers were Stevenson screens in 1896, therefore none of the early readings count. The presence of non-standardized records renders the others useless. Who knew?
  3. Since some thermometers were older types called Glaisher or Greenwich Screens, their data is unusable, even though there are decades of temperatures comparing the two types of screens and they are remarkably similar.
  4. Even though Stevenson screens were installed across Australia between 1880 – 1910, since they were new (ahem), they were likely to be warped and cracked, and therefore not acceptable. After that date they were better maintained (except they still needed a lot of downward adjustment).

There is a lot of data comparing older screens to newer ones. As Nicholls and Lewis mention:

The results of this 61-year experiment show that summer daytime temperatures measured using the Glaisher Stand are, on average, 1C warmer than in the Stevenson Screen.

Is it really beyond the power of the BOM to subtract 1 C from the old readings? They don’t seem to have any trouble subtracting 2C from the newer and better Stevenson screens. (Heck even 50C can vanish.)

As far as the claims of hiding things goes, the BOM carve it both ways. While they never mention the older temperatures in polite company, they publish details in graphs and tables on their site and then claim they hide nothing, as if the average person in West Wyalong will listen to the ABC news then check the depths of the climate data online.

I agree that it is a stretch for George Christensen to definitively declare “it was hotter” in 1896. It might have been, but all our surface data, even our current data is such a mess I wouldn’t put a definitive statement on anything. But Nicholls and Lewis are focusing on that, and are doing their best to avoid the real point skeptics are making. It doesn’t really matter whether it was 0.1 degree Celsius hotter or colder in 1896, what matters is that Australians no longer feel they can trust the BOM to give them the whole story about the climate. The BOM exhibit no curiosity about older hotter records, and make no effort to use any of the data — even though some of it can be used to extend some sites and some states back into the hot era of the late 1800’s. That is why skeptics are calling for an inquiry.

The BOM can’t churn out press releases announcing record after record and yet hide the historic heat of the Federation Drought. They slice and dice the permutations of every version of hottest autumn weekend, or warmest winter night since 1953, yet few Australians know that often hotter temperatures were recorded, all across Australia, back in the 1800’s.  That too is why skeptics are objecting — the imbalance in the public declarations. The BOM never admit that in some towns and some places it probably was hotter.

See more of the historic heat, strange adjustments well as these other related posts:


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