Crunching (an inquiry into) numbers, BoM homogenization to come under independent scrutiny. Greenie Watch posted this (pay-walled) from The Australian:
Upping the heat on climate number-crunchers
(John Ray) This major attack on Warmist crooks in high places appeared in Australia’s national daily. I think Americans will have little difficulty in mentally converting the cricket metaphor into a baseball metaphor
CRICKET legend Donald Bradman is a useful metaphor for the escalating global row over claims the world’s leading climate agencies have been messing with the weather.
Imagine, for instance, if some bureau of sport were to revise the Don’s batting average in Test cricket down from 99.94 to 75 after adjusting for anomalies and deleting innings of 200 runs or more.
What if the bureau then claimed another batsman had exceeded the Don’s revamped record to become the greatest ever?
Critics could be told the adjustments “don’t matter” because they had not affected overall global batting averages. Just as many batsmen had been adjusted up as down. And complaints could easily be dismissed as the “cherrypicking” of a few, isolated batsmen.
David Stockwell, Australian Research Council grant recipient and adjunct researcher at Central Queensland University, raised the Bradman analogy in his submission to a newly formed independent panel that will oversee the operation of the Bureau of Meteorology’s national temperature dataset.
Stockwell was highlighting public concerns at the BoM’s use of homogenisation techniques to adjust historical temperature records to remove anomalies and produce a national dataset called ACORN-SAT (Australian Climate Observations Reference Network — Surface Air Temperature). The panel, or technical advisory forum, which will hold its first discussions with BoM staff on Monday, was formed in December after a series of questions were raised publicly about the treatment of historic temperature records that has resulted in temperature trends at some Australian sites being changed from long-term cooling to warming.
Liberal senator Simon Birmingham, former parliamentary secretary to Environment Minister Greg Hunt, instructed BoM to fast-track the appointment of the panel, which was recommended in 2011 in a peer review of ACORN-SAT’s establishment. The make-up of the panel was announced by Birmingham’s replacement as parliamentary secretary, Bob Baldwin, in January.
In the meantime, controversy about homogenisation of climate records has exploded into a global concern after similar trend changes to those raised in Australia were identified in Paraguay and in the Arctic. Accusations of “fraud” and “criminality” have been made against some of the world’s leading weather agencies. There is now the prospect of a US Senate inquiry.
Respected US climate scientist Judith Curry has facilitated a wideranging debate on the issue, saying more research was needed, but that it is probably not the “smoking gun” for climate science, as some had claimed.
There is a long history regarding complaints about how climate data has been handled by authorities and how poorly those making complaints have been treated.
The general trend is made clear in a 2007 email exchange, now known as Climategate, between a senior BoM official and scientists at East Anglia University in Britain. BoM’s David Jones said Australian sceptics could be easily dissuaded if deluged with data.
“Fortunately in Australia our sceptics are rather scientifically incompetent,” Jones wrote. “It is also easier for us in that we have a policy of providing any complainer with every single station observation when they question our data (this usually snows them)”, he said.
Even better, noted East Anglia University’s Phil Jones, was to give troublemakers a big package of data with key information missing, making it impossible to decipher.
But more than seven years on, as the world’s weather bureaus report more and more broken temperature records and further examples emerge of incongruous adjustments, the pressure is building for a transparent process to finally untangle the numbers.
In Australia, ACORN-SAT was created in 2009 to replace BoM’s so-called high-quality dataset after questions were raised about the quality and accuracy of that network.
ACORN-SAT, which the Senate was told this week is managed by a two-person team in BoM, uses information from a select range of weather stations and computer modelling to compile its national temperature record. The data is also used to help create the global temperature record.
The panel to oversee ACORN-SAT will be headed by CSIRO scientist Ron Sandland and includes a wide range of experts in statistics and mathematics.
Sandland tells Inquirer he will hold a teleconference with BoM on Monday to decide how the process would be run.
The panel was first recommended by a peer review in September 2011 headed by Ken Matthews. The peer review gave ACORN-SAT a glowing report, describing it as conforming to world’s best practice. But it also called for greater transparency, better communication and independent oversight.
Despite criticisms about transparency and the results of homogenisation at some sites by members of the public, BoM was slow to act on the peer review recommendation to establish a technical advisory forum.
BoM is one of Australia’s most widely trusted organisations. Millions of people use its online weather services and a Senate estimates hearing was told this week that more than 30,000 people followed BoM’s Twitter feed in the wake of cyclones Marcia and Lam, which landed simultaneously in Queensland and the Northern Territory this week.
However, as one of the government’s lead agencies on climate change, BoM has come under greater scrutiny. A vocal chorus has been claiming that there is a pattern of historic temperatures being reduced to make the warming trend of the late 21st century look more acute.
The questioners were quickly labelled “amateurs” by atmospheric scientist David Karoly, from the University of Melbourne, as he and other climate science academics rushed to support BoM’s work.
But the issue has exploded internationally following a declaration by US agencies NASA and the National Oceanic and Atmospheric Administration that 2014 was the hottest year on record. As in Australia, regions were found where warming temperature trends had been created or increased through a process of homogenising records with neighbouring areas, some in other countries hundreds of kilometres away.
Published examples include Paraguay in South America and the Arctic, where a warm period in the 1930s and a well-documented period of intense cold around 1970 were erased from the record by homogenisation to give a steady rising temperature trend.
“How can we believe in ‘global warming’ when the temperature records providing the ‘evidence’ for that warming cannot be trusted?” asked British contrarian and climate change sceptic James Dellingpole.
“I’m not saying there has been no 20th-century global warming, I think there probably has been,” he said. “But I don’t honestly know. The worrying part … is that neither — it would appear — do the scientists.”
The website of Britain’s The Sunday Telegraph registered more than 30,000 comments under an article by columnist Christopher Booker saying the fiddling of temperature data has been “the biggest science scandal ever”. “What is now needed is a meticulous analysis of all the data, to establish just how far these adjustments have distorted the picture the world has been given,” Booker wrote.
The integrity of global temperature records after homogenisation is fiercely defended by global climate agencies, despite the fact that satellite measurements available from 1979 show a slightly different warming trend to surface-based records.
Australia’s BoM has issued two statements ahead of the Sandland review panel. In one it says temperature records are influenced by a range of factors such as changes to site surrounds, measurement methods and the relocation of stations.
“Such changes introduce biases into the climate record that need to be adjusted for, prior to analysis,’’ BoM says.
“Adjusting for these biases, a process known as homogenisation is carried out by meteorological authorities around the world as best practice, to ensure that climate data is consistent through time.”
BoM’s American counterpart, NOAA’s National Climatic Data Centre, says for global temperatures it is important to keep in mind that the largest adjustment in the global surface temperature record occurs over the oceans.
“All NOAA methodologies go through the peer-review process standard in scientific inquiry,” it says. Despite this, there remains enormous and heated debate about the issue.
Climate scientist Curry has opened an online debate that includes key scientists from the independent organisation Berkeley Earth, which compiles its own global temperature record, the results of which accord with those of other international agencies.
The Berkeley scientists conclude that Dellingpole and Booker’s claims of the “biggest fraud” of all time and a “criminal action” by climate scientists amount to nothing.
“Globally, the effect of adjustments is minor because on average the biases that require adjustments mostly cancel each other out,” they say.
But their web post generated heated discussion covering both the science of homogenisation and the standing of science.
European climate change economist Richard Tol, responding to Curry’s post, says the more important question raised by the debate over temperatures is perhaps why the public has lost so much trust in climate science that it prefers to believe columnists such as Booker over climate scientists at Berkeley. A Telegraph poll suggested that 90 per cent of 110,000 readers had sided with Booker.
“I would hypothesise that the constant stream of climate nonsense — we’re all gonna die, last chance to save the planet, climate change is coming to blow over your house and eat your dog — has made people rather suspicious of anything climate ‘scientists’ say,” according to Tol.
“If my hypothesis is correct, instead of arguing with Booker about the details of homogenisation, you should call out the alarmists.”
Curry tells Inquirer her main conclusions from the heated exchange in response to the Berkeley post are that “the stated uncertainties in global average temperatures are too small”.
“More research needs to be done to understand the impacts of the adjustments and to make individual locations more consistent with the historical record,” she says.
She says much more data work is needed to clarify the temperatures in the Arctic, which is a big source of difference among the different datasets in the northern hemisphere.
“I suspect that all this won’t change the qualitative result from the dataset, that is that the Earth is warming,” Curry says.
The way in which the Australian review of the BoM ACORN-SAT data is conducted could go a long way towards answering some of the questions being asked worldwide.
A common criticism of climate authorities such as BoM is that justifications for temperature smoothing may sound reasonable in the broad, but are often poorly explained in the detail of individual adjustments.
It is the task of the high-powered review panel to satisfy itself that the integrity given to BoM’s dataset by the initial peer review has been maintained.
Sitting on the panel with Sandland will be:
* Bob Vincent, emeritus professor in the school of chemistry and physics at the University of Adelaide.
* Phillip Gould, from the Australian Bureau of Statistics.
* John Henstridge, who founded Data Analysis Australia, now the largest private statistical organisation in Australia,
* Susan Linacre, a former president of the International Association of Survey Statisticians.
* Michael Martin, professor of statistics in the research school of finance, actuarial studies and applied statistics at Australian National University.
* Patty Solomon, professor of statistical bioinformatics at the University of Adelaide.
* Terry Speed, a former president of the Institute of Mathematical Statistics.
Declining an invitation for David Jones, BoM’s manager of climate change and prediction, to write for Inquirer, a BoM spokeswoman says establishment of the technical advisory forum will provide “an independent framework for quality assurance tests and analysis of the bureau’s climate dataset, and it would not be appropriate to pre-empt this process.”
But critics of BoM are already lining up to have their questions answered.
Research academic Jennifer Marohasy has accused BoM of using “creative accounting practices” in both the homogenisation of data to remodel individual series as well as the choice of stations and time periods when the individual series are combined to calculate a national average for each year.
Marohasy says BoM’s methodologies have turned a cycle of warming and cooling over the past century into one of continuous warming.
In a submission to the review group, Marohasy makes three recommendations to render the overall official national temperature trend for Australia “more consistent with history, and reasonable accounting practices”.
The first is to use the same locations when calculating average mean temperatures for different years.
Marohasy’s research shows that while the national average temperature is calculated from a set of just 104 weather stations, the same 104 stations are not used every year.
“In particular, hotter places are added later in the time series, which currently begins in 1910”, she says.
“For example, Wilcannia is a very hot town in western NSW.
“There is a long continuous maximum temperature record for Wilcannia that extends back to 1881, but the bureau only adds Wilcannia into the mix from 1957.
“Obviously, if the national average temperature is calculated from a mix of hotter locations in the 1990s than, say, in the 1920s, then it will appear that Australia was hotter in the 1990s, even if the temperatures at individual weather recording stations were the same during these two periods,” Marohasy says.
Her second recommendation is to start the official record from 1880, not 1910, thus including the hot years of the Federation drought in the official record.
Lastly, Marohasy says adjustments should not be made to temperature series unless an irregularity exists in the original series that was caused by a known, documented change in the equipment at that weather recording station and/or a known change in the siting of the equipment.
Her view is supported by retired certified practising accountant Merrick Thomson, who has told the panel there is a lack of transparency associated with the change in the mix of weather stations used to calculate the national average.
Thomson says when BoM transitioned to the new ACORN-SAT system in 2012 it removed 57 stations from its calculations, replacing them with 36 on average hotter stations.
“I calculate that this had the effect of increasing the recorded Australian average temperature by 0.42C, independently of any actual real change in temperature,” Thompson says.
“Of the 57 stations removed from the calculation of the national average temperature, only three have actually closed as weather stations,” he adds.
Thomson asks the panel: “Why was the mix of stations changed with the transition to ACORN-SAT, and why was this not explained and declared, particularly given that it has resulted in a large increase in the 2013 annual temperature for Australia, I calculate 0.56 degree Celsius?”
He asks what criteria were used to determine whether a station becomes part of the national network.
Stockwell says although many had rushed to defend the BoM, saying the adjustments “don’t matter” as they do not change the global temperature graphs appreciably, they clearly do matter to a lot of people.
In a submission to the panel, Stockwell highlights what he considered unsound practices by BoM in handling the national data.
“Every portrayal of historical data should be historically accurate,” he says, “else it becomes revisionism and strays out of the domain of science and into the domain of ideology and politics.”
Self-declared “citizen scientist” Ken Stewart has been more pointed. “The apparent lack of quality assurance means ACORN-SAT is not fit for the purpose of serious climate analysis including the calculation of annual temperature trends, identifying hottest or coldest days on record, analysing the intensity, duration and frequency of heatwaves, matching rainfall with temperature, calculating monthly means or medians, and calculating diurnal temperature range,” he says.
“In conclusion, ACORN-SAT is not reliable and should be scrapped.
“ACORN-SAT shows adjustments that distort the temperature record and do not follow the stated procedures in the bureau’s own technical papers, generating warming biases at a large number of sites, thus greatly increasing the network wide trends,” Stewart says in his submission.
“Furthermore, the bureau does not take account of uncertainty, and the data are generally riddled with errors indicating poor quality assurance.
“Finally, its authors have not followed up on most undertakings made more than three years ago to permit replication and improve transparency.
The obvious and widespread depth of feeling about BoM’s treatment of historical records underscores the wisdom of recommendations made by the 2011 ACORN-SAT peer review.
The review panel encouraged BoM to improve the public transparency of ACORN-SAT arrangements.
“This will not only build public confidence in the dataset but should assist the bureau in its continuous improvement efforts and its responsiveness to data users,” the peer review panel said.
“The panel also encourages the bureau to more systematically document the process used, and to be used, in the development and operations of ACORN-SAT.
“Some aspects of current arrangements for measurement, curation and analysis are non-transparent even internally, and are therefore subject to significant ‘key persons risk’, as well as inconsistency over time.”
Current criticism of BoM over the temperature series is obviously unfamiliar territory for what remains one of Australia’s most highly regarded public institutions.
This criticism is by no means an existential threat to BoM but a rigorous and transparent review of ACORN-SAT data, methodology and communication is clearly needed, and long overdue.