Several chapters of Climate Science: The Facts raise really serious issues about the temperature records maintained by the Bureau of Meteorology (the Bureau). In addition to the adjustment (homogenisation) of records and the trashing of old files investigators met bureaucratic obstruction to keep the management processes out of sight.
One of Tony Abbott’s last moves as PM was to set in train an investigation into the operations of the Bureau but that initiative was aborted by the incoming PM Turnbull. This is understandable given the importance of fake science and fake news to sustain the push to destroy the electrical grid of the nation.
Joanne Nova described mysterious revisions to Australia’s long hot history that were located by a team of well qualified and experienced volunteer citizen scientists. The story really has to be read to get the full flavour. For example they found that thermometers accurate to a tenth of a degree were being adjusted by as much as two degrees. The records now indicate that the hottest day recorded in modern history was at Albany on the coast of WA rather than in the baked arid zones of Oodnadatta or Marble Bar. The temperature reported in Albany on 8 February 1933 was 44C and 8 decades this was adjusted by 7C to 51. This pipped the 50.7 that was recorded for Oodnadatta on 2 January 1960.
New electronic thermometers were widely installed in the 1990s and many ran alongside the old system which would permit comparison of the old and new systems but the data are not available to the public and are routinely deleted as a part of normal practice. It is likely that the new system generates a “step up” in recorded temperatures but it appears that the trashing of records has eliminated the possibility of a proper investigation.
Early explorers were trained to record temperatures and there are masses of newspaper records that indicate weather patterns around the nation with many accounts of temperatures around 125F “in the shade” translating into 52C. On 3 January 1909 an observer recorded 125F at Bourke. The handwritten entry was underlined as one might do for a remarkable reading. Decades later this was declared an error for two reasons: it was taken on Sunday when the observers didn’t normally work and the temperature at some other towns in midwestern NSW only hit 113F. On the first point, why would an observer NOT make an effort to record a potentially record-breaking temperature? On the second, a newspapers reported a figure of 123 at Brewarinna which is the nearest town to Bourke.
This team joined forces with Senator Bernardi to ask for an audit of the historical records from the Australian National Audit Office in 2011 but the Bureau announced a major revision of the data called the Australian Climate Observation Reference Network – Surface Air Temperature (ACORN-SAT) which sidestepped the audit because the request referred to the old data set, now unused and possibly deleted.
Jennifer Marohasy described the homogenisation of Rutherglen, a town in the Victorian wine country a little west of Albury. The temperatures were recorded at the agricultural research station since 1912 in a Stevenson screen, a wooden structure designed to standardise the immediate environment of the equipment. Very strange things happened in the course of homogenising the data for the new ACORN-SAT system. A cooling trend of 0.3C at the station is converted into a statistically significant warming of 1.6C per century, ignoring trends at nearby stations. The story is complex involving tables of data and helpful charts so I will not try to tell more of it here – just beg, borrow or steal the book if you are too poor or mean to buy it.
When Greg Hunt announced that the investigation of the Bureau would not proceed under the new management he explained to Tony Jones on Lateline that the Bureau used hard science, hard data, literally millions of data points of information through our satellite and local monitoring. Marohasy wrote that ACORN-SAT relies entirely on surface data from 112 stations, 109 of which are homogenised. Satellite readings are not involved which means that the acronym SAT is as deceptive as the information provided.
Marohasy and Dr Jaco Vlok wrote Chapter 10 “Moving in Unison: Maximum Temperatures from Victoria, Australia. Dr Vlok is apparently a refugee from South Africa, now engaged in research at the University of Tasmania (my alma mater) on building historical temperature records using artificial neural networks (don’t ask me).
The work in this chapter does not call for sophisticated mechanical or electronic analysis, merely the technique known as “eyeballing” in the technical language of the trade, using the neural network connected to your eyes. This involves more charts and I strongly suggest that you eyeball them. They simply show all the raw data for maximum temperature series in Victoria that are available, starting with some in 1860. To summarize, all the series move together suggesting that they are all reflecting the same reality, the same variations and changes over the many decades. “But there is no long-term trend. There are, however, cycles of warming and cooling with the warmest periods corresponding with times of drought.”