I’ve wrote a few weeks ago about the nagging problem of the measurement of temperature. The basic weather data are collected by national meteorological bodies, both as a public service for citizens and also for ships, aeroplanes and other transport media. There is a World Meteorological Organisation, which has established standards that nations are urged to follow. The developed countries do so, while the developing countries do their best. It is most important that the data are accurate, because the utility of forecasts depends on their reliability and validity.
Over the last few years those with a sceptical mind have begun to be concerned about the reliability and validity of the data underlying the forecasts and reports issued by our Bureau of Meteorology, the British Met Bureau and their counterparts in the USA. Indeed, like Jo Nova, I wondered in print last year whether or not the BoM was best described as a PR outfit for global warming, pushing the view of the then Gillard Government.
Dr Jennifer Marohasy, whose website is listed on my blogroll, has been a persistent critic of the Bureau’s methodology, and has put forward actual examples of places, like Bourke in NSW and Rutherglen in Victoria, where the actual data have been ‘homogenised’, or adjusted, so that what would have been a cooling trend over time has become a significant warming trend. Others, like Tom Quirk, Des Moore and William Kininmonth, have raised their own comparable questions, mostly in Quadrant. As I’ve explained in the past, when new instruments are brought in, or data-collecting stations are moved, because the site is no longer appropriate (there are rules about the desirable local environment of thermometers, for example), the organisation has to make a choice. Do you end one trend and start anew ? Do you make an adjustment for what you think would have been the case had the new station always been where it has now been placed? And if you do, on what basis do you make the adjustment?
Well, the Bureau steadfastly declined to deal with these inconvenient questions, and it was only recently, after one of Dr Marohasy’s papers had an MP (Dr Dennis Jensen, a scientist himself) as a co-investigator, and her investigations began to be noticed internationally, that it offered any response. You can read it in The Conversation, a government-funded website to allow academics to voice their thoughts and opinions. The authors are both strong supporters of the IPCC, and one of them, Dr Andy Pitman, is most dismissive of sceptics: the sceptics are so well funded, so well organized, have nothing else to do, they kind of don’t have day jobs, they can put all of their efforts into misinforming and miscommunicating climate science to the public, whereas the climate scientists have day jobs and this isn’t one of them. He said this in an ABC interview. I don’t know where he gets this guff from, but it is mind-bendingly inaccurate as far as I am concerned, and indeed as far as all the sceptics I know are concerned.
Well, you ask, what was the response. It was bland and unhelpful. Its tone comes across as superior and condescending. Over the past week or so, the Bureau of Meteorology has stood accused of fudging its temperature data records to emphasise warming, in a series of articles in The Australian. The accusation hinges on the method that the Bureau uses to remove non-climate-related changes in its weather station data, referred to as “data homogenisation”. If true, this would be very serious because these data sets underpin major climate research projects, including deducing how much Australia is warming. But it’s not true.
Great, you think. Now they’ll show why it isn’t true. Alas, no. There are many methods, they say, to deal with ‘inhomogeneities’ (an unlovely word), and the Bureau uses a technique ‘that can adjust the data to make sure it is consistent through time’. What is it? Well, we never learn, but are directed to a 2010 article by a senior Bureau official, Blair Trewin, which is a well written summary of the problems that face organisations like his when they try to deal with missing and new data. But the paper doesn’t answer the question, and that was not its intention. By this time you’d be expecting the authors at least to pick up the two named sites, Bourke and Rutherglen, and show what was done, and why. The Bureau had a go, claiming that one of the adjustments must have been caused by a station move. Then a retired Bureau official who worked in the area said that was news to him.
The authors of The Conversation piece didn’t try that one on. They ramble on, claiming that if the Bureau hadn’t homogenised the data the outcome would have been an apparently and inaccurately hotter Australia, and finish with the lofty slap-down to the effect that if you’re unhappy with what the Bureau does, your task is to show how the Bureau is wrong, in a paper to be submitted to a peer-reviewed journal. Then they’ll take you seriously. Really! The contempt for those who raise questions is apparent.
Once again, this is dreadful, empty stuff, though this time it comes from the Bureau’s supporters, rather than from the Bureau itself. It cannot be all that difficult to present a few cases where the adjustments have led to cooling over time rather than warming or to show in much more detail actually what happens and why that gives a preferred outcome for reasons that would be clear to anybody.
Until that is done, this dispute will go on indefinitely, to the growing discredit of the Bureau.