THE Australian Bureau of Meteorology keeps remodelling the temperature record for Australia – and not just by a little bit. Temperatures are changed through a process known as homogenisation, and then changed again, sometimes by as much as 6.4 degrees Celsius for the one day.
For example, on 8th February 1933 the maximum temperature as measured at Albany in Western Australia was 44.8 degrees Celsius. Then, six years ago it was changed to 51.2 degrees Celsius! Recently it was changed again, this time to 49.5.
Changing the temperature record like this is not unusual for institutions such as the Australian Bureau of Meteorology, though the extent of the change for Albany on this day in 1933, and also the direction of the change, is unusual.
Usually past temperatures are cooled relative to the present as part of remodelling, which is called ‘homogenisation’. Cooling the past relative to the present has the effect of exaggerating global warming.
Given the magnitude and direction of this change to the Albany temperatures, which was first made six years ago, several of us asked the Bureau: ‘Why’?
Why was the temperature at Albany on this day (February 8, 1933) adjusted-up by so much (6.4 degrees) in the official version 1 of the ACORN-SAT dataset that was published six years ago?
I never got an answer.
I have simply been told, mostly via the mainstream media, that homogenisation is world’s best practice, and that ACORN-SAT is scientific.
Of course, it is not scientific to make such changes to temperature measurements, though this type of change – this remodelling – is standard practice not only for our Bureau but also for the custodians of the global temperature datasets relied upon by the IPCC (United Nation’s Intergovernmental Panel on Climate Change).
While ACORN-SAT Version 1 contains remodelled temperature values that can vary from the actual recorded measurement by more than 6 degrees, the values in this same database are often referred to as ‘observations’ as though they represent real measurements. For example, when leading climate scientist Sophie Lewis and David Karoly published a paper in the American Meteorological Society journal about ‘extreme events’ they erroneous refer to ACORN-SAT Version 1 values as ‘observations’.
Indeed, ACORN-SAT Version 1 has underpinned almost all the climate change work at our universities and at CSIRO over the last 6 years.
Most climate scientists seem to want to believe that the temperature values that they are working with represent real measurements. But they don’t!
Just recently this ACORN-SAT database – used by Lewis, Karoly and thousands of other scientists here in Australia and also overseas – was updated. Dr Blair Trewin at the Bureau has re-adjusted temperature values yet again, creating ACORN-SAT Version 2.
In the case of Albany, the maximum temperature on 8th February 1933 is now shown as 49.5 degrees Celsius. In reality it the maximum temperature in Albany on that day back in 1933 was 44.8 degrees Celsius.
The integrity of the historical temperature record is of extraordinary importance. This record also underpins belief in catastrophic human-caused global warming.
Perhaps today’s front-page story in The Australian newspaper by Graham Lloyd will generate some interest in how and why our climate history can be so change, apparently at the whim of the Bureau and other such institutions around the world.
I wait, and I hope.
Peter Meadows says
Thanks Jennifer. What the BoM is doing is a disgrace but who, apart from you and a few others, will call it out, and who in authority will take a blind bit of notice of it? We can only hope that over the next few years the forecast drop in temperatures does occur in significant measure, while CO2 continues to increase, to the point where the discrepancy cannot be ignored.
Shaun Long says
Thank you Jennifer for this important work.
Geoffrey Williams says
Jennifer, this business of B.O.M changing past temperatures in the name of homogenization is not only highly qustionable but is a disgrace to ‘proper and transparent, scientific procedures’. I am sure that the public both here in Australia and worldwide have no understanding that they are being ‘duped’ by an elite group of climate change ideologists. If not for people like yourself this lying and cheating would go unnoticed. Please keep up your good work in highlighting these issues.
Mike says
A nation thrives on trust. When government agencies like the BEST M tell lies, what hope have we got?
spangled drongo says
The BoM today have just demonstrated the great Orwellian move to eradicate our current standards and values.
Yesterday our average temperature rounded to the nearest whole number was less than half a degree cooler in 1910 and less than half a degree warmer in 2017, using a graph with a midway under/over line.
This made our warming zero when taken to the nearest whole number.
This morning, thanks to these “necessary” adjustments we now have a warming of 2c when applying the same rounding.
Thanks to no error bars we can plainly see that we have now reached catastrophic warming already and we must forthwith destroy our free-market culture to rectify this problem.
Shane Gresinger says
How can we trust todays records which has been manipulated so much.
We must keep the original records intact along with the raw data for future generations.
I do not trust todays records because of the manipulation of those records.
I now use the last 21000 years to see if we are outside the range of natural variability, which shows me we are still within that band.
Thank God we still have honest scientists like Jennifer.
C. Paul Barreira says
Having wandered about the BOM’s website for a time I find myself no less bemused by the notion of “homogenisation” than I was before, certainly I have received no sense of enlightenment.
So I continue to wonder why, just to take the records for one day as an example, the numbers differ so much. The middle days of January 1908 in South Australia were simply awful. Take 15 January in particular. The BOM says the temperature on West Terrace reached 43.1 degrees C or 109.6 degrees F. The “Advertiser” (16 Jan 1908, p. 10) reports the temperature as having reached 111.4 degrees F. or 44.1 degrees C.
It is revealing of purpose that nothing, apparently, explains the difference. One wonders whether the BOM took advice from a volume published in 2000 entitled “The Historian’s Conscience”. In this volume of short essays one learns nothing to do with the conscience of the historian but a great deal about manipulating the mind of the reader.
The situation is a bit serious for the notion may evolve that the BOM should lose its funding (see comments to that effect in ). I do not agree and argued as much saying that we may have simply to wait for internal reform to occur, provoked either by the collapse of the contemporary notion of “climate change” or much more serious parliamentary oversight, the former being the more likely with the latter following suit. Still, the parliament should require of the BOM complete descriptions of the process of homogenisation and how they apply to any temperature at any location on any given date.
cohenite says
I should have financed a couple of parallel temperature sites back when you and Lance wanted to do it Jennifer.
What a travesty when the temperature record is so untrustworthy yet $billions of policy decisions are based on it.
Rod says
Send this on to Allan Jones at 2GB , everyone needs to hear this
Ian Duncan says
Thanks yet again Jen. Keep at ’em. Someone needs to try to steer them back on track. I don’t understand why they don’t just throw out the poor data and retain the most accurate stations. I would more trust the Raw data as opposed to some government homogenised garbage. Surely even back in the late 1800s there were people like your grandfather all over Australia taking readings as accurately as they possibly could. If they…our BOM… are happy to accept an homogenised change upward of 6.4 C then surely the Raw data would have been acceptable in the first place.
I think things are starting to change in the minds of the general public though. Just yesterday I was surprise to receive a message from friends of mine who have finally ‘seen the light’ after I kept encouraging them to just watch some of the presentations on Frolly1000s YouTube channel. Patrick Moore from my point of view is the one person whose presentations are most likely to convince the firm ‘believers’.
William Taylor says
Thanks for another excellent post, Jennifer.
Unfortunately, the article you link to in The Australian is behind a paywall. Any chance you could post an excerpt?
Thanks,
William in Brooklyn
DaveR says
ACORN-2, developed secretly and released without any observation period, creates a larger AGW signal than ACORN-1, and both are significantly larger than the raw data. Trouble with both Acorns is that the magnitude of the claimed AGW signal is less than the magnitude of the adjustments.
Scientific best practice? Prove it by releasing the homogenisation methodology to the public.
Our BOM, in lock-step with the British Met Office, New Zealand’s NIWA and the notorious CRU at the University of East Anglia. Rotten institutions all.
Graham Falconer says
There was a dramatic change in the situ of Stevenson Schemes in the early 1970,s when the main temperature stations were Department of Agriculture, prior to this period the temperature were recorded from watered lawns they were then changed to dry area, which wot result in increased day temperatures but I will bet the minimums are now lower.
James says
We can’t rely on the BOM data. Therefore nor can scientists, academics or politicians.
The Australian government should halt any policies driven by the belief in dangerous man made global warming, until a satisfactory, independent and publicly scrutinized audit can be done of all historical temperature data being relied upon by policy makers.
The adjusted temperature data is not tracking even close to the average UN IPCC accepted climate model which are running too warm. The unadjusted temperature observations are even cooler, as are satellite and balloon temperature observations.
Global sea temperatures, Antarctic and Arctic ice levels, and the frequency and severity of severe weather events, are other observations which are refusing to follow the dangerous man made climate change narrative. Not that you would know that from legacy mainstream media reports.
If the theories and predictions of the so-called climate ‘consensus’ were accurate and reliable, and the science was ‘settled’ at least as far back as when Al Gore said it was, you have to ask, why have past temperature records been adjusted in recent years?
And why wont any of those bodies adjusting the global temperature records, make their station by station adjustments and notes publicly available?
And why have many of those organisations fought through the courts, to avoid having those temperature adjustments independently audited?
Ian George says
These are the changes to daily temps for Bourke, Jan 1939 between ACORN 2, ACORN 1 and AWAP (raw temps).
Date A/N2 A/N1 Raw
1/01/1939 38.1 38.4 38.9
2/01/1939 39.3 39.1 40.0
3/01/1939 41.3 41.9 42.2
4/01/1939 37.6 37.9 38.1
5/01/1939 38.1 38.4 38.9
6/01/1939 40.9 41.5 41.7
7/01/1939 40.9 41.5 41.7
8/01/1939 42.7 43.0 43.4
9/01/1939 45.4 45.7 46.1
10/01/1939 47.6 47.9 48.3
11/01/1939 46.5 46.8 47.2
12/01/1939 45.5 45.8 46.2
13/01/1939 45.0 45.3 45.7
14/01/1939 45.4 45.7 46.1
15/01/1939 46.5 46.8 47.2
16/01/1939 46.0 46.3 46.7
17/01/1939 39.3 39.1 40.0
18/01/1939 39.3 39.1 40.1
19/01/1939 39.3 39.1 40.0
20/01/1939 41.0 41.7 41.9
21/01/1939 41.7 42.1 42.5
22/01/1939 43.5 43.8 44.2
23/01/1939 36.3 36.5 36.7
24/01/1939 39.4 39.2 40.3
25/01/1939 36.2 36.5 36.6
26/01/1939 30.0 29.5 29.4
27/01/1939 29.9 29.4 29.3
28/01/1939 29.2 28.9 28.8
29/01/1939 31.3 30.5 30.6
30/01/1939 35.3 35.4 35.6
31/01/1939 38.0 38.3 38.6
The original AWAP maximum mean for this period was 40.4C.
After ACORN 1 it was down to 40.03C.
After ACORN 2 it is now 39.9C.
That’s a drop of 0.41C in two homogenisations.
Note how lower temps have been increased but higher have been decreased (is this a form of covering up so the overall adjustments don’t look as bad?).
Can’t wait for ACORN 3.
Jill says
Like the unemployed rate each month, Seasonally adjusted Load of garbage to suit the current loonies.
This weather is cyclictic , what goes around comes around, they can’t change that.
Aert Driessen says
Well done Jennifer, keep up the good work. You’re a real patriot, unlike the white ants at BoM. Where is the Office of the Chief Scientist in all this?
Ray says
Another example of the unethical and unprofessional behaviour of BOM, whose leadership unquestionably accepts the ideology of dangerous anthropogenic global warming.
Ian MacCulloch says
It is not scientific but it sure is illuminating. If you go, and I sure you have, to the Trove website you will find some of the most descriptive newspaper articles on heat waves in the 19th & 20 century – especially around parts of western NSW. In fact, it was so bad the government of the day gave free rail passes to those who wanted to travel to cooler areas of the state. (https://trove.nla.gov.au)
Need a good dead fish story – stacks of those for all years in the Darling Basin in particular. How odd that events such as this are highly repetitive.
Les Atkins says
Very good work. The public beliefs driven by one sided A.B.C corporate ideology accepts records without question.
For example, sea temperature readings are accepted to be historically higher therefore bleaching coral. There is never mention of higher sea temperatures at the cooler southern end of the Great Barrier Reef increasing so as to provide conditions favourable to coral growth.
Mark McGuire says
Wait. What?
Now, Stephen Briggs from the European Space Agency’s Directorate of Earth Observation says that surface air temperature data is the worst indicator of global climate that can be used, describing it as “lousy”.
Scientists are now trying to simulate the behaviour using computer models.
This is difficult because the behaviour of the deep ocean is too poorly known to be reliably included.
“The models don’t have the skill we thought they had.
That’s the problem,” said Peter Jan van Leeuwen, director of the National Centre of Earth Observation at the University of Reading.
https://www.theguardian.com/science/2014/jun/13/pause-global-warming-data-sea-level-rises