THIS last summer has been hot in Australia. But was it the hottest ever? Summer 80 years ago was arguably as hot, if not hotter. Back then more ferocious bushfires burnt larger areas.
Yet Australia’s Environment Minister, Melissa Price, recently claimed this summer’s bushfires as a consequence of climate change. I grew up with stories from my late father of terrible bushfires – infernos – back in 1939. The Black Friday bushfires destroyed four times the area of farmland and forest as the devastating February 2009 fires – and twenty times as much as burnt this last summer. Ash from that bushfire fell as far away as New Zealand.
My father described hot and hungry years in rural Victoria back then – just as John Steinbeck described farm life in the mid-west of the US in the 1930s in his famous ‘Grapes of Wrath’. There was hardship, and there were dust storms in the US and also in south-eastern Australia.
In rural Victoria, the summer of 1938-1939 was on average at least two degrees hotter than anything measured with equivalent equipment since.
Yet Minister Price denies this history – my late father’s history. She is relying on temperature data that has been extensive remodelled. This remodelling is justified by the Australian Bureau of Meteorology on the basis that temperatures are now measured using a non-standard method (spot readings) from non-standard equipment (custom built probes in automatic weather stations). Apparently, we need to know how hot it was back then, relative to the equipment used now.
On 13 January 1939 my father was living not far from Rutherglen, near Australia’s longest river, the Murray River. He described a hot wind blowing from the north west.
The Rutherglen agricultural research station has one of the longest, continuous, temperature records for anywhere in rural Victoria. Minimum and maximum temperatures were first recorded at Rutherglen using standard and calibrated equipment back in November 1912. Considering the first 85 years of summer temperatures – unadjusted/not homogenized – the very hottest summer on record at Rutherglen is the summer of 1938/1939.
While this last summer of 2018/2019 was hotter according to Minister Price, such a claim would not pass scrutiny if assessed for the Guinness Book of records – because of all the changes to the way temperatures are now measured at Rutherglen relative to that summer back in 1938/1939.
At Rutherglen, the first big change happened on 29 January 1998. That is when the mercury and alcohol thermometers were replaced with an electronic probe – custom built to the Australian Bureau of Meteorology’s own standard, with the specifications still yet to be made public.
According to Bureau policy, when such a major equipment change occurs there should be at least three years (preferably five) of overlapping/parallel temperature recordings, except the mercury and alcohol thermometers (used to measure maximum and minimum temperatures, respectively) were removed on exactly the same day the custom-built probe was placed into the Stevenson screen at Rutherglen, in direct contravention of this policy.
In 2011, the Bureau made further changes in that it stopped averaging one-second readings from the probe at Rutherglen over one minute. The maximum temperature as recorded each day at Rutherglen is now the highest one-second spot reading from the custom-built probe. That is correct – spot reading.
So, to reiterate, we now have a non-standard method of measuring (spot readings) from non-standard equipment (custom-built probes) making it impossible to establish the equivalence of recent temperatures from Rutherglen – or any of the Bureau’s other 695 probes in automatic weather stations spread across the landmass of Australia – with historical data.
Then there is the remodelling – with the most recent remodelling creating Version 2 of ACORN-SAT. This has resulted in an overall 23 per cent increase in the rate of warming between Versions 1 and 2 for the 112 weather stations that comprise ACORN-SAT. This is the database used by the Bureau and the CSIRO to monitor climate change across Australia.
At Rutherglen, a modest rate of warming in the raw maximum temperatures of 0.7 degrees Celsius per Century has been changed to 1.3 degrees Celsius in ACORN-SAT Version 2. Changes to the minimum temperature trend are more dramatic: a slight cooling trend of 0.3 degrees Celsius has been changed to warming of 1.9 degrees in ACORN-SAT Version 2 for Rutherglen.
This remodelling – known as homogenisation – involves the detection of discontinuities and then adjustments which generally result in past temperatures being cooled relative to the present. By cooling the past, present temperatures appear hotter. For example, considering maximum temperatures at Rutherglen, the largest single drop-down (adjustment) to daily temperatures occurs from 1 January 1938 back in time. The Bureau classifies the hot summer of 1938/1939 as a ‘discontinuity’ that is ‘statistical’ in ‘cause’ and then cools all the days before 31 December 1938 by 0.6 degrees Celsius back to 1912 – the beginning of the record.*
This is an embarrassment to the scientific method, and an insult to the 71 lives lost on 13 January 1939.
To repeat, the Bureau does not deny making these changes. Rather it claims such changes to Rutherglen’s temperature history are necessary to show what the temperature would be back then, using today’s equipment. But there was no actual change in the equipment between Versions 1 and 2 of ACORN-SAT for Rutherglen. So, this reason makes no sense.
The remodelling of Rutherglen, and the other 111 stations that comprise ACORN-SAT is extensive and misleading. It was correctly described as ‘fraud’ by commentator Rowan Dean on Sky Television on Sunday 10th March.
So why did, for example, the Bureau drop the minimum daily temperatures by a further 2.6 degrees Celsius on the day of the Black Friday bushfire? To be clear, the minimum temperature on the day of the Black Friday bushfire at Rutherglen was measured as 28.3 degrees Celsius. This value is changed to 27.8 degrees Celsius in ACORN-SAT Version 1, a reduction of 0.5 degrees Celsius. In Version 2, the temperature is reduced further, now archived as just 25.7 degrees Celsius for 13 January 1939 – a reduction of 2.6 degrees from the original temperature as actually recorded on that day.
There is a real history of rural Victoria: 71 men and women did perished in that bushfire back on 13 January 1939. According to my late father, it was extraordinarily hot and the wind was blowing from the north west.
The Bureau has never put a media release out letting the Australian public know that there is a Version 2 of ACORN-SAT, with even cooler historical temperatures for Rutherglen and most of the rest of Australia than in Version 1 that was only published in 2012.
Just a few years ago, the minister then responsible for the Bureau, Greg Hunt, was claiming that ACORN-SAT Version 1 was the world’s best practice and the correct temperature history of Australia. Now, we have ACORN-SAT Version 2, and temperatures overall have been warmed a further 23 percent relative to Version 1.
The remodelling by the Bureau is industrial-scale: this is necessary to generate a consistent global warming trend that does not exist in the raw unhomogenized data from rural and regional Australia.
There are consequences for future generations in this remodelling. It affects how we understand the relationship between climate and bushfires. Also, by continually reducing past temperatures, there is potential for new record hot days, record hot summers and hottest years for even cooler weather. Recommend wellbutrin buy .
This is nonsense – consistent with how the Bureau now measures and remodels our temperature history.
A different version of this article was first published at The Spectator: https://www.spectator.com.au/2019/03/the-hottest-summer-on-record-except-for-the-ones-that-weve-changed/
*I’m quoting from the ‘Adjustment Summary’ for ACORN-SAT Version 1 published in September 2014.
Perhaps this record from Corowa* can help with the fine details.
The Argus, Melbourne, Vic. Thu 12 Jan 1939 Page 4
“Corowa’s Big Double!
COROWA combined two all-time
records In a most distressing com-
bination to-day, when the maximum
temperature Was 118deg. In the shade
and the barometer reached the ex-
traordinarily low reading of 27.9
* Cowra is about 320 Kms (about 200 miles) from Rutherglen. Jen 8pm
Ken Stewart says
Good work Jen. We can’t keep the bastards honest, but we can at least let them know we’re onto them- as you do.
Jen, is their any reason at all to alter any of the pre-1998 mercury thermometer temperature records from Rutherglen?
Or for other outback weather stations with continuous mercury thermometer records?
Jennifer. Wahgunyah say next?
All these places are far too easy to mix up.
If you want to get to Coreen from Rutherglen head through Corowa but for Cowan go past Cowra.
Corowa is a town on the Murray. Cowra on the Lachlan is the area where I grew up. As we drove into our little nearby town the sign said “Goolagong” but if you came in from the other side of town the sign said “Gooloogong”.
I again live near the Lachlan. 20Ks closer to Goulburn than Cowra.
Now with the help of computers we don’t need to mix up towns manually any more. The BoM can do it so well its called homogenised when complete. Then can be done again (ACORN 2) just for fun. It could be easier for them with pre-confused meta data.
Corowa on the Murray has a good long thermometer record but is not fully digitised. The BoM have the highest “evah” temperature there as 46 Deg C but the newspaper has 118 F (48.8 C). So backs your case against ACORN . Just hope the daily data from Corowa has not been lost.
Peter Wheeler says
Jennifer summer (January) 1932 was also very hot according to some old records and many newspaper reports. Have you looked at this one as well? Cheers Peter
Ian Thomson says
Siliggy, your comment takes me back to a story I was told, (dunno how true), about the large police station in the small town of Carinda, in NW NSW. It was reputed to have been designed for Corindi, on the coast, hence its size.
Sounds right to me, for Syderny knowledge.
Well I don’t know how true the story is about the Bell at Braidwood St Bede’s church. The locals tell the story and it possibly changes like Chinese whispers with every telling. It is too big for the building at 1.625 metric tons so has its own tower outside. Been there ever since the Bullock team brought it up along the muddy tracks in 1862 only to find it was meant to go to one of the “Bedes” of St Mary’s cathedral in Sydney ( The arch bishop or his assistant).
It seems the BoM may have made similar mistakes. There are two “climate data online” records that give Lats and Longs just north of Albury. One for rainfall and one for both rainfall and monthly temperature. “Woodlands (Murrumbateman) 074225” and “Jindera (Murrumbateman) 074134”. I have checked and the rainfall records correlate well for the four year overlap with records around the N.S.W. town of Murrumbateman, 224 km away. Jindera post office, Brae springs and Albury around where the boM puts these records, the same edge of a grazing dam with lots of zeros in the identical Lats and Longs, does not.
Not hard to mix up Jindera, Gindera and Gininderra either it seems. If you shorten Gininderra to gindera the same way we shorten Wagga Wagga to Wagga.
“On Saturday last a Cricket match was
played on the Gininderra ground, One Tree
Hill, between, Ginderra and Gungahleen.
Owing to time being called before Gininderra
finished their second innings, Gungahleen
was the winner.” “*”
‘Siliggy, your comment takes me back to a story I was told, (dunno how true), about the large police station in the small town of Carinda, in NW NSW.’
I also heard about that when I lived out near Walgett in the 90s.
Had the opportunity to go to Carinda and I believe it’s true.
Here’s the Google capture.