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Blame dry weather and electronic sensors for a lot of Australia’s warming trend…
In this provocative report, retired research scientist Bill Johnston analyzes Australian weather records in a fairly sophisticated and very detailed way, and finds they are “wholly unsuitable” for calculating long term trends. He uses a multi-pronged approach looking at temperatures, historical documents, statistical step changes, and in a novel process studies the way temperature varies with rainfall as well.
His two major findings are that local rainfall (or lack of) has a major impact on temperatures in a town, and that the introduction of the electronic sensors in the mid 1990s caused an abrupt step increase in maximum temperatures across Australia. There will be a lot more to say about these findings in coming months — the questions they raise are very pointed. Reading, between the lines, if Johnston is right, a lot of the advertised record heat across Australia has more to do with equipment changes, homogenisation, and rainfall patterns than a long term trend.
Bill Johnston: On Data Quality [PDF]
“Trends are not steps; and temperature changes due to station changes, instruments and processing is not climate change”, he […]
Wait til you see what Lance Pidgeon has found. He was looking at the BOM website temperature archive maps of Australia for early last century (using AWAP data). He was wondering how the Bureau of Meteorology could possibly create maps this detailed for specific days that long ago. He was especially curious about the remote, vast areas where there were no thermometers, yet there were wiggly jiggly temperature lines on the map, shaded as if they had meaning. I’ve heard that more people have visited the South pole, than have stood at the point in central Australia where the three large western and central states meet.
Then he noticed something positively strange — April 14th in 1915 and one year later in 1916 looked almost identical, as did the same day in 1917. The more he looked, the weirder things got. He plodded, year after year, all the way from 1911 to 1917, then through Jan, Feb, March, and so on. Worse, he tells me he could keep going right through to 1956 without seeing much change (though there are interesting exceptions). After that, temperatures of the area start to vary from year to year, like the “weather” we’d […]
The Australian Bureau of Meteorology have been struck by the most incredible bad luck. The fickle thermometers of Australia have been ruining climate records for 150 years, and the BOM have done a masterful job of recreating our “correct” climate trends, despite the data. Bob Fernley-Jones decided to help show the world how clever the BOM are. (Call them the Bureau of Magic).
Firstly there were the Horoscope-thermometers — which need adjustments that are different for each calendar month of the year — up in December, down in January, up in February… These thermometers flip on Jan 1 each year from reading nearly 1°C too warm all of December, to being more than 1°C too cold for all of January . Then come February 1, they flip again. Somehow the BOM managed to unravel this bizarre pattern (cue X-files music) and figure out exactly what anti-horoscope-adjustments to use (and they were different in every city). Modestly the BOM did not explain to the public how clever their adjustments were; despite their $300m budget, it took volunteer Bob Fernley-Jones to reverse out the Special Horoscope Cure, and find the square wave algorithm that repaired our damaged climate records. Lucky for the […]
There are adjustments on top of adjustments. Homogenised records are being used to correct raw records. Some man-made adjustments can infect data for miles around…
Rutherglen is a long running station in central Victoria. There are no documented site moves, but the long raw trend of slow cooling was adjusted up to a warming trend. What was cooling of 0.35C per century became a 1.7C warming trend.
Jennifer Marohasy, and others, have spent months trying to get answers from the BOM explaining why these massive adjustments were made. Excuses flowed. In the latest round, the BOM claim the changes are necessary to make the Rutherglen record match the trends in the neighboring stations. What the BOM doesn’t say is that there was no warming in the neighbours either, not until after they were homogenized. The order in which stations are homogenized matters, which rather says something important about the arbitrary nature of the adjustments. Anomalous trends from far distant and poor locations can spread through waves of homogenization until better, longer stations succumb to political correctness and show the “correct” result. Small choices about which stations to to use first in the process can make a huge difference to the […]
There is some major messing with data going on.
What would you say if you knew that the official Perth thermometer was accurate at recording minimums for most of time in October in the eighties, but 0.7°C too warm all of December, and 1.2°C too cool in January? Bizarrely that same thermometer was back to being too warm in February! Try to imagine what situation could affect that thermometer, and require post hoc corrections of this “monthly” nature. Then imagine what could make that same pattern happen year after year. All those weather reports we listened to in Perth in 1984 were wrong (apparently). And this bizarre calendar of corrections is turning up all over Australia.
Bob Fernley-Jones has looked closely at all the adjustments done to achieve the wonderful homogenized ACORN data, as compared to the theoretically “raw” records listed in Climate Data Online (CDO) on the BOM website. He can’t know what the BOM did (since they won’t tell anyone), but he knows the outcome of their homogenization. He was shocked when he noticed a strange square-wave pattern repeating year after year; he was astonished that there were corrections calendar month by calendar month, up and down, switching […]
The hot desert border of Western and South Australia
Lance Pidgeon has drawn my attention to the mysteriously detailed weather maps of the Australian BOM, with their mass of contradictions. The intricate squiggles of air temperature profiles suggests an awesome array of data — especially remarkable in places like “Cook”, which is a railway station with a population of four. Eucla, the megopolis in the map, has a population of 368. The shared border in the map (right) is 674km long top to bottom.
Thankfully, after 80 years of modern technology, the weather at Eucla and in the Great Victorian Desert is much more bearable than anyone would have expected. The BOM ACORN data set works better than airconditioning. In places near Eucla, where old newspapers record 43C, the BOM tells us the highest maximum that month was “under 27C”. Far to the north of there, the highest maximum stayed under 36C, but the average for that same whole month was above 36C. Go figure. It’s a new kind of maths… [or maybe the miracle of reverse cycle a/c?]
There are a half million square kilometers in this map here and almost no […]
Two out of three Australians live in our capital cities where the longest and best resourced temperature records would be found. These are the places where the weather reports matter to the most people on a daily basis — and where headlines about records and trends will be widely discussed. But these are also the sites which have been affected by the growth of concrete and skyscrapers, and potentially have the largest urban heat island (UHI) effect, so might need the largest adjustments.
Bob Fernley-Jones has been going through the BOM records for six of Australia’s state capitals, looking at the original raw data (at least, as is recorded in the BOM’s climate data online, called CDO). Bob compares the new “corrected” dataset called ACORN for these locations — that’s the all new marvelous adjusted data. He finds many step changes that can’t be explained by known site moves or the UHI effect. Many step changes occur in either minima or maxima, but not in both at the same time, which is also odd. As we already know, the adjustments usually cool the past — especially the minima (see all the blue lines on graphs below […]
Let’s play the Heatwaves PR game. If CO2 had an effect we’d see a significant increase in the rate of global warming over the decades since WWII, the models would work, and climate scientists would be able to predict our climate. Since none of that is true, those with a political agenda have to clutch at noisy but marketable extremes instead. Apparently even a half-true, noisy, non-causal link is good enough for post-modern scientists.
Heatwaves are perfect for generating scientific sounding fear, but not so useful for generating actual scientific knowledge. There are an infinity of ways to measure them. They can last 3 days – 160 days, and be cut off at any number from 35 – 40C, or at some percentile outlier. They can be measured one town at a time, or on a regional or state-wide level. The permutations are rich with headline scoring possibilities. And in the end, on a long warming trend that started 300 years ago, it is obvious, inevitable, and predictable that we should score more now. What’s surprising is how often we don’t.
On ABC radio before Easter, Dr Vertessy, Director and CEO of the Bureau of Meteorology, claimed that we are […]
More errors in ACORN — The Bureau of Met wonder-database corrects for mysterious “statisticals” but not for 15 story buildings built next to the thermometers. They correct a step change that doesn’t occur in minima, but don’t correct for one that does in maxima. Big site changes are marked in some datasets but not in others. And where is the correction for obvious urban heat island effects? Bear in mind, the size of the artificial steps and corrections is on a par with the warming supposedly due to carbon dioxide. Hmmm.
The BoM database needs to be independently and publicly replicated, all the way from their raw data to the final output down to several decimal places. Then we will all know what is going on. Let’s shine a light in. If it ain’t replicated, it ain’t science.
Melbourne has one of the longest temperature records in the Southern Hemisphere. Looking at the original records it appears Melbourne maximums have not changed much from 1855 – 1995. Then they suddenly jumped or stepped up.
Tom Quirk did some sleuthing, and figured out why that happened. But what he can’t figure out is why the Bureau missed this adjustment, yet makes […]
UPDATE: *Chris has been over the entire dataset again, and makes a correction that adjustments account for 30-40% of the rise. A bit less than half. Headline updated. See his site for the newer stats. March 9, 2015
Adjustments that cool historic temperatures have almost doubled Australia’s rate of warming.
CSIR published “Meteorological Data” 1855 – 1931
There was a time back in 1933 when the CSIRO was called CSIR and meteorologists figured that with 74 years of weather data on Australia, they really ought to publish a serious document collating all the monthly averages at hundreds of weather stations around Australia. Little did they know that years later, despite their best efforts, much of the same data would be forgotten and unused or would be adjusted, decades after the fact, and sometimes by as much as one or two degrees. Twenty years later The Commonwealth Bureau of Census and Statistics would publish an Official Year Book of Australia which included the mean temperature readings from 1911 to 1940 at 44 locations.
Chris Gillham has spent months poring over both these historic datasets, as well as the BoM’s Climate Data Online (CDO) which has the recent temperatures […]
When it comes to our rare high-quality historic records, and the real long term trends of Australian weather, the silence is striking. There are some excellent historical records of long term temperature data from the late 1800s in Australia, which lie underused and largely ignored by the BOM.
For the BOM, history almost appears to start in 1910, yet the modern type of Stevenson screen thermometer was installed across Australia starting as early as 1884 in Adelaide. Most stations in Queensland were converted as long ago as 1889 and in South Australia by 1892. Though states like NSW and Victoria were delayed until 1908.
Here’s a photo of the ones in Brisbane in 1890.
Brisbane was recording temperatures with modern Stevenson screens in 1890, as were some other stations, but the BOM often ignores these long records.
The BOM don’t often mention all their older temperature data. They argue that all the recordings then were not taken with standardized equipment. The BOM prefers to start long term graphs and trends from 1910 (except when they start in 1950 or 1970, or 1993).
The BOM was set up in 1908. Before that there were Stevenson screens going in […]
UPDATE: 6pm — Despite the hype, the BOM shows no towns making 50C in WA. Marble Bar was the hottest at 49.0C. At least, the BOM, WA Today, The Australian and the ABC have printed the old record correctly as 49.2C.
Will it be a hottest record at one of the hottest towns in the world today? The forecast for Marble Bar, Western Australia, is 49C. The record for Marble Bar stands at 49.2C or 120.5F recorded in 1905 and 1922. I guess if we give up our cars and airconditioners the temperatures in Marble Bar will go back to these ideal conditions?
Thermometer-spotting: the temperature has varied up and down.| The BOM page for Marble Bar: 48.3C at 2.54pm but the highest was 48.9C at 2:46 (8 minutes earlier?). | At 3:30pm the current temp is 48.4C but the highest as listed as 49C at 3:12pm. | Now at 3:50pm the temperature has fallen to 47.9C and it looks like the peak was reached just short of the old record.
Overexcited journalists get 50C into headlines already
Sat Jan 14, 1905
At least one journalist is so excited he predicted it’s “highly likely” […]
What really happened in 1878?
The raw data at Nobby’s near Newcastle (graphed below) shows monster heat in 1878, 1879, and 1883 — far hotter than modern times. Its unlikely that it was recorded with modern equipment, so it’s hard to compare. Was it really hotter? We don’t know when the Stevenson screen was installed. I went hunting through our wonderful historic Trove archive of old newspaper records. It doesn’t help us make any accurate comparisons, or even tell us about annual averages, but there is a remarkable story of exceptional heat and dryness in January 1877 that few Australians know. Let’s revisit the times of forgotten people who lived when CO2 was perfect and the climate was ideal.
How hot were the 1800s in Australia? My favorite quote is about the miners near Braidwood (in the mountains between Canberra and the coast). It reached 108F but look at the cultural norms:
“Years ago in the valley the miners always ‘knocked off’ if the thermometer registered 112 degrees (44.4C) in the shade, but times and wages are changed now, and the poor men are willing, to work on days like last Friday 18.1.78″ (see the Freeman’s Journal link […]
The headlines are burning around the nation: 2014 was the hottest ever spring! Except it wasn’t. The UAH satellite coverage sees all of Australia, day and night, and are not affected by urban heat, airport tarmacs, “gaps in the stations”, or inexplicable adjustments.
When will the Bureau of Meteorology discover satellites? How many years will it take to train the ABC journalists to ask the BOM if satellite measurements agree or disagree with their highly adjusted, altered, deleted, and homogenised ground stations?
I used exactly no tax dollars to email John Christy of UAH, get the latest data, and graph it to show that in Australia 2014 was not the hottest spring, and not the hottest winter, summer or autumn either. Why can’t the BOM or the $1.1 billion ABC do that?
The obsession with cherry picked, unscientific and irrelevant single season records that are not even records shows how unscientific the Bureau of Met is. By its actions we see a diligent PR and marketing agency. If the BOM served the public, they would make sure the public knew that these records depend entirely on their choice of dataset and on their mysterious homogenization procedures. If the BOM were […]
Neville Nicholls and Sophie Lewis are striking back at George Christensen, MP, who accused the BOM of “wiping” the official records of heat waves in 1896 and demanded an inquiry. For some reason, despite their world class work, Nicholls and Lewis still don’t seem keen on having an inquiry — so they go to some length to explain why it’s “false” to say it was hotter in 1896 than it was in 2013. Oddly though, to come to this conclusion they don’t use BOM work, because the BOM concluded “it would be very difficult to compare the 19th-century temperature data with modern observations.” Instead that difficult task was done by Berkley. Nichols calls it “brave”, but a “fact” at the same time.
In their long article, what they don’t explain is why they almost never mention any of the hundreds of ultra hot historic temperatures in their press releases and national news. George was “wrong”, and that’s a “fact” we’re told, but most of their article on The Conversation explains why we don’t know what the temperature was in 1896. Try not to get confused.
That old data is dodgy see — I’ll paraphrase: Satellites agree with the BOM. (Seriously, […]
Which causes more summer heatwaves: carbon dioxide or Bureau of Meteorology (BOM) adjustments?
Ken Stewart has analyzed the adjustments used to create the all-new ACORN wonder dataset and compared them with another BOM dataset called AWAP, and finds, extraordinarily, that the trend in average summer maximums has been tripled by adjustments that the BOM imply are neutral.
Since summer maxima are the ones used to generate the most headlines in Australia, I ask again if the Bureau of Meteorology is a scientific agency or a PR group? Increasing the trend in summer maxima would produce more headlines of hottest ever month, season, heatwave, and weekend.
In this graph Stewart splits the data into months, and compares the trends in maxima in the AWAP and ACORN datasets, across the entire nation. We see that most of the adjustments happen to data from the hottest months of the year, October to March. Even though the measured maxima in February and March are possibly cooler now than they were in the early 1900s, they have been adjusted to show warming trends.
When was the last time you heard the BOM tell you that their “hottest ever” February record depended on adjusting down the […]
Once upon a time, Australian climate scientists discussed and published climate trends of the late 1800s. And lo, the long lost hot weather decades were apparent in many places in inland South Eastern Australia. While skeptics are accused of cherry picking data from Bourke, Rutherglen and Deniliquin, there are plenty of other examples. In the last post, the 1953 Argus story described hotter drier summers in Omeo, Bendigo, Hay, Bourke, Alice Springs, Echuca, Albury, and Cooma. Here is a Deacon et al peer reviewed graph of the long term trends at Hay, Narrabri, Bourke and Alice Springs.
Thanks to Chris Gillham for finding the Deacon paper of 1952. [On another point, I’ll have a response up to the new BOM “adjustments” page later. In short, their data still has many inexplicable errors like where maxima are lower than minima, and they are still not providing all the details we need to replicate their data and homogenization methods. – Jo]
But just have a look at this graph. Degrees Fahrenheit of course. State of the art, 1952.
….
These cooling trends cover “only” a couple of million square kilometers of Australia:
The location of Alice Springs, Bourke, Narrabri, and […]
The average maximum temperatures [of SE Australia] during the last 35 years were between two and four degrees (F) lower than the average for the previous 35 years. — CSIRO 1953
Once upon a time — before the Great Politicization of Climate Science — CSIRO was able to analyze trends from 1880 to 1910. In 1953 CSIRO scientists were making a case that large parts of Australia had been hotter in the 1880s and around the turn of last century. They are referring specifically to summer maximums, and presumably the increase in rainfall over the same period played a large role in preventing hot days from becoming hotter. Minimum and mean trends may have been quite different, but these older maximum records are surely relevant when news headlines are drafted today about hot summers and heatwaves.
So what happened to the widespread lost hot decades?
I have a lot more to say on the warm and the work of these scientists. For the moment, the full archived news story is entertaining in its own right. Thanks to Chris Gillham for this link and to Jennifer Marohasy. Graphs tomorrow : – )
— Jo
The Argus (Melbourne, Vic) Wednesday 18 […]
The list goes on, and there is more to come.
In Deniliquin NSW, the homogenisation has lifted both the maxima and minima trends — again converting cooling to warming.
Graham Lloyd continues to increase the pressure on the Australian Bureau of Meteorology. In answers to Lloyd the BOM could only defend their work with the extraordinary statement that while some trends at individual stations look anomalous, overall the results “showed a similar warming trend to that of other international climate organisations. ”
So they inadvertently admit that they expect Australian trends to look like trends in other parts of the world. Despite the fact that Australia is drier, flatter and surrounded on every edge by oceans, the Bureau would consider it a fail if our trends were different to others? We’re in the opposite hemisphere to many international climate organizations, which may or may not matter, but we’ll never find out if we are trying to fit our data to theirs. And El Nino’s and La Nina’s mean very different things to countries on opposite sides of the Pacific. We’re blurring the resolution from thousands of data-points. The raw data is blended not just on regional scales but thanks […]
Was January 3rd 1909 in Bourke one of Australia’s hottest days ever?
The historic records say “125F” — or 51.7C. The BOM say it was an observer error.
Bourke and neighboring stations in NSW and QLD Australia
Blair Trewin wrote a paper looking at the extreme highs in 1997. The Bourke record was made on a Sunday and in that particular year there are no records on other Sundays. On the other hand, I wonder what station observer would not notice a day that was 125F and head in to work to see exactly how high it was. The number 125F was handwritten in and underlined. You’d think observers would know it was a special figure, and pay attention.
The town of Bourke got a Stephenson Screen only a few months beforehand in August 1908, so it had good modern equipment. But Trewin thinks the record is an observer error, and points out that it was a lot warmer in Bourke than in other surrounding towns like Thargomindah, Walgett, and Coonable, and by about 6.9C degrees, which is an unusual gap. During the rest of the month Bourke was “not exceptionally hot compared to other stations”. […]
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