An update on my recent post about Catalyst.
Most viewers (myself included) would not have realised that the “330 months since February 1985 of above average temperatures” reference had nothing to do with Australia, but was in fact based on an as yet unpublished paper by Dr Mark Howden of the CSIRO, who seems to have obtained his data from the NCDC. (Unpublished? So not yet peer-reviewed? Tut-tut, ABC!) As it is not yet published, we can’t access it or check Dr Howden’s methods and calculations, so the 1:100,000 chance of having 330 months in a row of above average temperature not being caused by the greenhouse effect seems a bit odd. 2 to the power of 330 is somewhat more than 100,000!
Whatever. I’m sure it’s very interesting. But that had nothing to do with the stated subject of the program, which was “Taking Australia’s Temperature”. It appeared to be thrown in as a late filler. Perhaps there was no deliberate deception planned, however to include that claim without clarifying that it was not Australian data but global data resulted in at least one viewer (me) being misled.
But let’s have a closer look at this claim, seeing as it has been raised. Yes the world has warmed, and so has Australia, over the last 100 or so years, somewhere between 0.4 and 0.7 degrees Celsius. Thanks to Chris Gillham, here is a graph of the NCDC data, from 1880.
I’ve marked in the period between 1944 and 1976, when there was a distinct cooling period.
Warming? Of course. Continuously? No. The warming has definitely slowed, plateaued, or possibly even reversed since 2001-2002.
Yet every month of this data series is above the average for the 20th Century, which apparently was reached at the beginning of 1985, so Dr Howden and the CSIRO are technically correct.
But let’s look at some completely different data.
In spite of the 1987 crash, the Asian bust, the GFC, every point since 1985 is above the value then.
Another example. Imagine driving from say Brisbane to western Queensland. The average altitude of Australia is 330m. Half way up the Toowoomba Range you pass this altitude. Past Toowoomba, driving across the fairly flat Darling Downs, be warned that every kilometre is above the average altitude. So when you reach Roma we can say that for more than 300 kilometres every kilometre has been above the average altitude. (OK, there are a few dips when you get close to Roma, but let’s homogenise them.) Scarey hey!
The point? The world has been warming since the mid 19th century. In a warming climate a point will eventually be reached where despite cooling episodes, every data point will be above the average. The little exercise with the wine bottles in Catalyst proves absolutely nothing, especially not about Australia’s temperature.
Oh, and by the way, the poor birds dropping dead in mid flight from the heat. The presenters failed to report that this is nothing new, and was documented in newspapers many times before World war II:-
The trouble is, some people believe the mis-information spread by the BOM, the CSIRO, and the ABC.