Jokers, and Temperature as Radio Chatter

From Jennifer Marohasy’s Blog

Jennifer Marohasy

I gave a talk yesterday, over Zoom , as you do nowadays, explaining that the Australian Bureau of Meteorology don’t really know how to measure temperatures anymore, so they take the recordings they have, and remodel them until it looks like how they think it should. That is then republished as an annual assessment of climate variability and change.

The assessment is published at the beginning of each year and advertised as an update, but the Bureau don’t always include the most relevant numbers – if they don’t feel like it. That might sound outrageous, and it is. But then again, the Bureau does what it wants to do. That has been the case since at least November 1996, when the transition began away from measuring temperatures using traditional liquid-in-glass thermometers which are mercury for maximum temperatures and alcohol for minimum temperatures.

Meteorologists often refer to the average temperature, but it would be misleading to think this is the average of all the temperatures measured say every hour over a day, or a month, or a year. Rather it is the highest temperature, and the lowest temperature as measured each day. These two extreme values are added together giving the daily mean.

Before November 1996, when most official maximum temperatures were measured with a mercury thermometer, the highest temperature was less extreme than it is now. This is because mercury in a glass tube, which is the essence of a mercury thermometer, takes some time to adjust to air temperature, so there is an amount of inertia.

Nowadays, the Bureau takes temperature readings every one second from what are called resistance probes and the very hottest of these instantaneous values is designated the maximum temperature for that day.

It is actually slightly more complicated.

If you will indulge my interest in all things technical – and concentrate intensely on what I write for just a moment or at least slightly longer than it took a probe to record the maximum temperature at the airport in Cordoba, Spain, a couple of weeks ago – a new record maximum for Spain for April. That was the media headline. What was not explained, because it spoils the story somewhat, and because people have trouble concentrating on detail, is that the temperature was recorded at an airport with the probe located between the runway tarmac and the taxiing apron.

In the olden days, maximum temperatures were recorded from places like botanical gardens by astronomers who sometimes also kept their telescopes there. They were fascinated with the natural environment and continually looking for new ways to measure it. Nowadays, it is the case that airports are the primary site across the world for recording temperatures, that are reported by meteorologists, often on the nightly news, with yet another record-breaking hot day more likely to increase viewer engagement. So, it is at the end of the day, month, and year that the weather report is analysed in terms of increased traffic volume metrics (for example clicks) rather than the meteorologist’s skill at predicting, for example, how much rain or snow actually fell.

This relatively new imperative is aided by not only having the probes at airports, where more frequent take offs and landings by ever more powerful jet engines, will continually increase the likelihood of a blast of hot air being recorded as the hottest day ever, but also by all the electrical noise.

For sure, I need to explain how this works.

A mercury thermometer is completely impervious to the beat of airport radar that may move across the tarmac every 30-40 seconds. Not so, what are referred to as ‘low noise’ amplifiers attempting to precisely measure the change in resistance of the platinum electrodes in the resistance probe: that is how the probes measures temperature. These electrodes may not only be energised every time the radar sweeps over them, but also by the chatter from a pilot in the airport’s control tower.

As an analogue engineer recently explained to me, because of all the radio interference at airports, it is not really a place to be recording temperatures with resistance probes. Yet this is exactly where most of these temperature recording devices are now located – and not just in Australia, but across the world. So, the average global mean temperature may not only include the blast from a jet plane landing at Cordoba, Spain, but also the chatter from pilots and the control tower because temperature is now primarily measured as changes in electrical current and at airports.

Of course, those measuring temperatures using these probes at airports would be working hard to exclude radio frequencies (RF) getting into the input of the receiving amplifier and causing random errors. At least one would hope so – unless they are jokers.

The real test of this is seeing how the readings from a mercury thermometer compare with readings from these resistance probes at airports – around the world.

The original Joker was of course the arch-criminal obsessed with absurdity and joke-based crimes: clown-like in appearance and personality, a master of intrigue and escape. And, so, I was pondering the number of times the Australian Bureau of Meteorology has escaped having to show the parallel data for my hometown of Brisbane – or any of its many other airport sites – despite multiple reviews, reports, advisory panels, and peer-reviewed studies rejecting claims that its temperature record is biased or flawed. Here I am quoting directly from the The Guardian on Sunday, an article by Graham Readfearn in which he seems to delight, perhaps as the joker’s sidekick, about how many times any proper review of these measurements has been rebuked, including a proposal by Senator Cory Bernardi, that there be some oversight by the National Audit Office.

Rather than show even Bill Johnston a limited amount of parallel data for Canberra airport back in 2014, when he made a Freedom of Information request, the Bureau destroyed it, or so the story goes.

In the ‘Batman and Robin’ episodes I watched as a child on an old black and white television, the Joker was ever elusive and in the most imaginative ways.

John Abbot, who like Johnston has made FOI requests for parallel temperature data from airports, wrote in The Australian newspaper – at about the time the new record hot temperature was being recorded from Cordoba airport in Spain – explaining how rather than provide some parallel data for Brisbane airport, the Bureau falsely claimed the data never existed.

In fact, a relatively small amount of the data that the jokers claimed did not exist was eventually provided to Abbot, by the same jokers just before Easter. That was on Thursday 6th April when the jokers sent Abbot 36 separate emails to which were variously attached a jumble of scans of over 1,000 handwritten reports.

As though anyone expects to receive scans of over 1,000 hand-written reports across 36 emails when they are told they will eventually be provided with parallel data for Brisbane airport for the three years August 2019 to July 2022.

Abbot immediate onforwarded the mess to me.

This is an extract from the Brisbane Airport Field Book. Temperatures as shown were recorded on 1st August 2019.

I will continue this story as part of a series I’m calling ‘Jokers, Off-Topic Reviews and Drinking from the Alcohol Thermometer’.

On the topic of alcohol following is how many times the Bureau has changed the alcohol thermometer measuring minimum temperatures at Brisbane Airport over the last two decades. One thermometer used to last 100 years.

A JUMBLE OF METADATA
Year Opened 1992/ Minimum Temperature
14/FEB/2000 INSTALL Thermometer, Alcohol, Min (Type Dobbie S/N – 18985) Surface Observations
06/MAY/2008 INSTALL Thermometer, Alcohol, Min (Type Dobbie S/N – 19048) Surface Observations
04/JUN/2012 INSTALL Thermometer, Alcohol, Min (Type Dobbie S/N – 19266) Surface Observations
06/MAY/2008 REMOVE Thermometer, Alcohol, Min (Type Dobbie S/N – 19266) Surface Observations
24/JUL/2020 REPLACE – (jtaylor2) Thermometer, Alcohol, Min (Now Amarol S/N – 33803) Surface Observations
05/AUG/2020 REPLACE – (jtaylor2) Thermometer, Alcohol, Min (Now Amarol S/N – 33849) Surface Observations
10/MAY/2019 REPLACE – (jtaylor2) Thermometer, Alcohol, Min (Now Dobbie S/N – 2546) Surface Observations
03/SEP/2015 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 19048) Surface Observations
24/NOV/2019 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 19048) Surface Observations
08/MAY/2013 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 23264) Surface Observations
06/MAY/2015 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 27637) Surface Observations
26/AUG/2015 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 27637) Surface Observations
19/MAR/2016 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 27637) Surface Observations
09/JUN/2013 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 27654) Surface Observations
29/MAY/2020 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 32894) Surface Observations
09/AUG/2020 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 32894) Surface Observations
29/JUL/2021 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 33820) Surface Observations
03/DEC/2020 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 33824) Surface Observations
09/JUN/2004 REPLACE Thermometer, Alcohol, Min (Now Dobbie S/N – 19048) Surface Observations
21/DEC/2005 REPLACE Thermometer, Alcohol, Min (Now Dobbie S/N – 19266) Surface Observations
10/JUL/2015 REPLACE Thermometer, Alcohol, Min (Now Dobbie S/N – 2546) Surface Observations
15/MAY/2016 REPLACE Thermometer, Alcohol, Min (Now WIKA S/N – 43095) Surface Observations

B. ANNUAL MAXIMUM TEMPERATURES FROM BRISBANE AIRPORT

These are some of the raw and adjusted/remodelled temperatures for Brisbane Airport, as I will explain in due course. In the meantime you can find more information at the interactive tables here https://jennifermarohasy.com/acorn-sat-v1-vs-v2/ and here
https://jennifermarohasy.com/wp-content/uploads/2022/03/Tmax_040842.png

END NOTES

Notes, and links, to some more of the topics mentioned above and much thanks to energy economist Alan Moran for organising the Zoom, and I will forward my notes in due course to you for the coal miners.

1. I confirmed on 3rd March 2021, that the Australian Bureau of Meteorology admitted, as I surmised in a blog post on 10th February, that the reference value for 2021 was not actually included in its calculation of the amount of warming as published in the 2021 Annual Climate Statement, more here; https://jennifermarohasy.com/2022/03/australias-broken-temperature-record-part-3/
In short, we have a 2021 Annual Climate Statement that does not include the new 2021 value in its calculations.

2. Paul Homewood sent me an email about the new hot day in Spain, and his email linked to a BBC article that you can read here: https://www.bbc.com/news/science-environment-65403381 . Homewood has a website and you can sign up for his emails.

3. I was so disappointed that Graham Readfearn got his article published last Sunday in The Guardian, quoting Ailie Gallant from Monash University. https://www.theguardian.com/science/2023/may/07/climate-scientists-first-laughed-at-a-bizarre-campaign-against-the-bom-then-came-the-harassment#:~:text=For%20more%20than%20a,Bureau%20of%20Meteorology%27s%20temperature%20records

4. Regarding Bill Johnston, you can read more about the Canberra airport saga here: https://joannenova.com.au/2017/08/another-bom-scandal-australian-climate-data-is-being-destroyed-as-routine-practice/

5. It is the case that John Abbot had some detail of the history of his interactions with the Bureau published by THE AUSTRALIAN and then republished by the Institute of Public Affairs:
‘BOM makes heavy weather over temperature data’ ’tis here https://ipa.org.au/research/climate-change-and-energy/bom-makes-heavy-weather-over-temperature-data

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May 11, 2023 2:19 pm

As we know, the adjustments have been going on for years and the validity of them is debatable in some cases. There is an upside coming though I think. If some past adjustments have unnecessarily cooled the past and warmed the present, then it is going to be very hard to maintain that “process” going forward, they have squeezed the last bit of toothpaste out of the tube. Going forward, we are likely to see many temp time series stall or fall due to the reporting of real temps. The USCRN is a classic example of this. A “pristine” network that should not need adjustment is showing now signs of dreaded climate change.

USCRN Data.png
Reply to  diggs
May 11, 2023 2:53 pm

Diggs,

It is actually quite the opposite.

There is so much warming ‘built into the system’ even a few cooler years tagged onto a linear trend, will mathematically inevitably show warming.

More here: https://jennifermarohasy.com/2022/02/australias-broken-temperature-record-part-2/

bdgwx
Reply to  diggs
May 11, 2023 4:33 pm

USCRN with no adjustments shows +0.52 F/decade of warming.

nClimDiv with adjustments shows +0.39 F/decade of warming.

Reply to  bdgwx
May 11, 2023 8:13 pm

Only because of the bulge from the 2015 El Nino on the right hand end.

El Nino’s are the “GO TO” for creating warming trends..

Thing is, they have nothing to do with CO2.

You FAIL. !

bdgwx
Reply to  bnice2000
May 12, 2023 8:27 am

ONI averaged -0.15 over the period of record of USCRN.

El Nino’s cause transient increases in the global average temperature.

La Nino’s cause transient decreases in the global average temperature.

It’s not clear to be that ENSO is correlated with the US average temperature. It’s possible that it is. It’s just not something I’ve looked into yet.

The USCRN timeseries itself does not tell us anything about what causes either the trend or the variation. In other words, you cannot eliminate any agent including CO2 as being a modulating factor.

Reply to  bnice2000
May 12, 2023 5:36 pm

“GO TO” for creating warming trends..

Love that. Yep draw the trend line to the El Nino and stop.

bdgwx
Reply to  siliggy
May 12, 2023 7:11 pm

Just to be clear. I did not draw the line to the El Nino. I drew it to the triple dip La Nina.

Reply to  bdgwx
May 11, 2023 11:26 pm

bdgwx, what exactly does the trend mean when it explains less than 2% of the variance? A simple time trend analysis shows no statistically significant temperature increase in the CRN monthly anomaly data you are referring to. Of course, why look at the aggregate weirdly calculated anomaly data? You can get monthly temperature data (or more frequently) by station and do the analysis correctly. I have yet to find a station where the deseasonalized data (12 difference) shows a statistically significant time trend.

bdgwx
Reply to  Nelson
May 12, 2023 8:23 am

A trend tells you how much the y value changes wrt to the x value. The variance in USCRN is 0.061 F^2. Subtracting the trend leaving only residuals results in a variance of 0.032 F^2. By that metric the trend explains 52% of the variance. The AR(1) corrected uncertainty of the trend is ±0.6 F/decade so we cannot say the trend shows statistically significant warming. However we can say with ~95% confidence that the trend is constrained between -0.08 F/decade and 1.12 F/decade. The trend is the same regardless whether of anomalies or absolute values are used. However, looking at the anomalies always us to compare USCRN with other datasets like nClimDiv. The comparison with nClimDiv tells us that PHA is more likely than not still underestimating the low bias caused by time-of-observation changes, instrument package changes, station relocations, station commissioning/decommissioning, etc.

sherro01
Reply to  diggs
May 12, 2023 4:42 am

Diggs,
Important point about toothpaste back in tube.
Most of the “cooling the past” BOM adjustments have a start date of 1910.
If the raw numbers were done again to start at 1900 or 1890, there would be a big, sudden cliff at 1910 when the adjustments are met. What to do? Cool the 1900-10 numbers a great deal to join up, then cool the 1890-1900 block even more to be smooth? Or, rewarm the numbers after 1910 to disappear the cliff?
No, none of these. The BOM method will be to continue to ignore numbers before 1910 as too inconvenient.
A long time ago, I reduced that telling the straightforward truth required less effort than fiddling the truth. You have to remember what lies you made up. Geoff S

fansome
May 11, 2023 2:27 pm

The electronic thermometer readings could be conditioned via a first-order lag circuit with a time constant of about 1-minute. That would remove the high frequency noise. A step change in temperature would take about 5-minutes to reach 99+% of the final step change. A first-order lag circuit is a simple R-C circuit. Easy to construct.

Reply to  fansome
May 11, 2023 3:42 pm

I’m not sure a lag filter will remove RF pulse noise injected into the circuitry. This isn’t constant noise that can be separated out but occurs as a regular pulse. If you knew the timing and amplitude of the pulse you might be able to design a filter in the digital space to remove it but otherwise it would be hard to distinguish it from natural variation.

You can see this in the newest amateur radio SDR radios. They do an exceptional job of removing constant hash but aren’t much better at removing lightning pulses than an old analog limiter or blanker circuit using a phase delay line to blank the signal out somewhere in the IF or AF chain.

This isn’t just a matter of trying to duplicate the “thermal inertia” of an analog sensor.

Reply to  Tim Gorman
May 11, 2023 10:04 pm

Jennifer’s post reports on superstitious whisperings from her secret analogue engineer, supported nought by a single speck of data (or even a schmik (one ten-thousand millionith of a speck)).

She should have added electronic flushing machines in the unisex bathrooms, Teslas waiting dutifully for their matched fob to pass by, x-rays and metal detectors, satellites tracking transponders and transponders tracking luggage …. the internet WUWT and everything (LOOKOUT there is one over there!!)

The fact is, her claim that automatic weather stations report statistically significant warmer temperatures than thermometers observed in the same screen, does not stand scrutiny. And if there no difference between instruments, and she won’t put her data in the public domain, everything else including whisperings, magical rays, kriptonite and even Batman and Robyn is superfluous.

Kind regards,

Dr Bill Johnston

http://www.bomwatch.com.au

old cocky
Reply to  Bill Johnston
May 11, 2023 10:46 pm

She should have added electronic flushing machines in the unisex bathrooms, Teslas waiting dutifully for their matched fob to pass by, x-rays and metal detectors, satellites tracking transponders and transponders tracking luggage …. the internet WUWT and everything (LOOKOUT there is one over there!!)

Don’t forget about the microwave oven at the Parkes radio observatory.

Reply to  Bill Johnston
May 12, 2023 4:46 am

You haven’t really proved anything here. What are the electronic shielding design criteria for automated temperature measurement stations? Are there any? I haven’t seen them.

If there are no standards then there *will* be impacts from external sources. It’s just hat simple.

Nick Stokes
May 11, 2023 2:36 pm

“On the topic of alcohol following is how many times the Bureau has changed the alcohol thermometer measuring minimum temperatures at Brisbane Airport over the last two decades.”
During all that time, Brisbane had an AWS, which was the primary instrument on which published data was based. They may well have operated several alcohol thermometers for other reasons.

Reply to  Nick Stokes
May 11, 2023 2:43 pm

It is interesting that before the Airport became the official site for reporting Brisbane temperatures, temperatures were recorded in the Botanical Gardens (Station No. 040214).

And according to the metadata for that station, there was only one mercury thermometer installed on 1 January 1840 and removed on 1 July 1994, when the station was closed.

And one alcohol thermometer to record minimum:

Minimum Temperature
01/JAN/1840 INSTALL Thermometer, Alcohol, Min (Type Unknown S/N – Unknown) Surface Observations
01/JUL/1994 REMOVE Thermometer, Alcohol, Min (Type Unknown S/N – Unknown) Surface Observations.

Equipment used to last a bit longer in the olden days, apparently. :-).

Rick C
Reply to  Jennifer Marohasy
May 11, 2023 3:43 pm

The meta-data is quite strange in some thermometers were installed several times sometimes just a few months apart, sometimes years apart. I first thought this might just reflect a routine recalibration cycles, but that doesn’t make sense due to the irregular intervals. It’s mystifying why there would be so many changes when clearly the thermometers were not replaced due to breakage or accuracy issues – wouldn’t reuse them if that were the case.

Stats: Period covered 14-Feb-2000 – 29-Jul- 2021
Number of Thermometer Changes: 22
Number of thermometers used: 14
Used 4 times: SN 19048
Used 3 times: SN 19266
Used 2 times: SN 27637, 2546, 32894

old cocky
Reply to  Rick C
May 11, 2023 3:53 pm

It would make a lot of sense to have a schedule to replace in-service instruments with freshly calibrated instruments. Presumable instruments which were still in spec would be retained in the pool.

Perhaps somebody here has first-hand knowledge of the service life and calibration intervals.

sherro01
Reply to  old cocky
May 12, 2023 4:59 am

o c,
As well as frequent calibration, there needs to be frequent reference to a fundamental, invariable standard. Like measurement of length is traced back to a 1 metre metal rod.
In analytical chemistry, we did about I repeat analysis for every 10 samples and about 1 analysis of a standard calibration material per 100 samples. We chatted the difference from the reference(s) daily with standard deviations of the differences.
With this thermometry, I have a concern that the sensors are not taken from the field weekly or monthly for reference to a standard like freezing water and boiling water. It seems that they can be out bush for a year or more. If that is the case, the method is unsafe (especially as to drift).
A further comment is that BOM do have real time filtering of electronic probe 1 second data. The method is described in BOM reports, but in general reading I have seen no description of how often the trigger is pulled on outliers in customary operating environments.
BOM have to understand that data paid for by the public must be available to the public.
There is no case for excessive money demands by BOM or refusals to supply data for undisclosed reasons. That is simply a denial of freedom of information, Big Brother at play. Geoff S

old cocky
Reply to  sherro01
May 12, 2023 5:31 am

As well as frequent calibration, there needs to be frequent reference to a fundamental, invariable standard. Like measurement of length is traced back to a 1 metre metal rod.

Calibration of workshop or field instruments is just one link in the traceability chain, with ever more accurate and precise versions as one approaches the ultimate reference.
I think the 1 metre rod is long gone, even “old number one” in France.

Nick Stokes
Reply to  Jennifer Marohasy
May 11, 2023 3:56 pm

Equipment used to last a bit longer in the olden days”

You don’t know why they were replaced. It looks to me as if thermometers were being tested before being sent out to country locations.

leefor
Reply to  Nick Stokes
May 11, 2023 7:39 pm

And then returned to Brisbane Aero. 😉

Nick Stokes
Reply to  leefor
May 11, 2023 8:50 pm

Unlikely.

leefor
Reply to  Nick Stokes
May 12, 2023 1:18 am

“29/MAY/2020 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 32894) Surface Observations
09/AUG/2020 REPLACE Thermometer, Alcohol, Min (Now Amarol S/N – 32894) Surface Observations”

Nick Stokes
Reply to  leefor
May 12, 2023 2:35 am

So what do you think is going on there? It’s pretty clear it isn’t wearing out.

leefor
Reply to  Nick Stokes
May 12, 2023 8:34 pm

But it was returned. Perhaps it is the technology and needs constant adjustments, for accuracy of course. 😉
But tell us why thermometers need to be adjusted for statistical purposes.

Reply to  Jennifer Marohasy
May 12, 2023 3:13 am

But Jenifer the site was not run by the Bureau, it was run by the Botanic Gardens people, who also pruned the roses and moved the sprinklers …

Read the site-summary disclaimer. There is no likelihood that the Bureau would know precisely who did what, when they shook too hard and thermometers broke or when instruments were replaced at sites they were not directly responsible for. Anyway, I thought you knew that most Bureau sites only started operating in June 1946.

Get some history girl. As my father used to say after defending Australia to within an inch of his life in Egypt and across Kokoda and copping a bullet, you need to study-up history and stats. More time in libraries and less face-time on TV.

You could start by reading my numerous in-depth reports on http://www.bomwatch.com.au. I recommend Amberley for example, and non-Bureau sites including Rutherglen, Cape Leeuwin, Marble Bar and the post office at Port Hedland.

So much to read and be expert in, and so little time between selfies and posts

I live in hope, but watch out for analogue-whisperers with no data, and high frequency fly-zappers, Q-rays, the ABC and and other purveyors of fascile facts. These include climate-dunces like Graham Readfearn, who apparently lives in Brisbane with a few backyard chooks, and also writes for The Guardian.

Obviously The Guardian knows the value of quality bullshit without doing a sniff-test.

Furthermore, forget the crickets. Woke has become nowke and with crickets now endangered, the new-nowke is fully sustainable blowies and dung beetles skewered on used toothpicks, freshly barbecued over recycled toilet-paper served on hand-cut lawn clippings at your virtuously-local walk-to green-store. I’m sure Graham Readfearn is woking on an anti-cricket pitch.

Distracted by arguing about things that make no difference, next it will be dung minus the blowflies and beetles …then save the toilet-paper rallies by schoolie-kids organised by Australian Youth for Climate Collation paid for by the Purves Environment Fund and WWF … three swipes for one, they will scream!

All because, while you are stuck in the fantasy hand-waving groove of differences that truly do not matter, I have shown on http://www.bomwatch.com.au, that the Bureau has provably changed the climate to agree with the narrative. If only you had undertaken regular weather observations and read some stats books.

You apparently don’t get the irony of the situation. Neither do you realise the folly of not getting it.

Yours sincerely,

Dr Bill

http://www.bomwatch.com.au

Reply to  Bill Johnston
May 12, 2023 7:03 am

Get some history girl. As my father used to say after defending Australia to within an inch of his life in Egypt and across Kokoda and copping a bullet, you need to study-up history and stats. More time in libraries and less face-time on TV.

Can you be any more condescending?

Reply to  karlomonte
May 12, 2023 2:25 pm

Dear karlomonte,

I’m sorry if you find my comments offensive, but frustration occasionally overtakes good manners.

There are three intertwined debates going-on here.

One relates to the claim that differences between maximum temperatures measured using thermometers verses those measured by automatic weather stations at two sites (Brisbane airport and Mildura), are significantly different.

The test JM refers to is a repeated measures or paired t-test of the hypothesis that the mean of the differences does not equal zero. The most important assumption on which the test depends is that successive differences (Delta at time1, Delta at time2 …. Delta at Time(n)) are independent (not autocorrelated), which for seasonally cycling daily data is an impossible ask.

As autocorrelation reduces the ‘noise’ component of the test (the pooled standard error, which is the denominator in the test equation), t increases, consequently the P-level is less, making it more likely to falsely reject the NULL hypothesis [which is that P(difference)= 0], i.e., to falsely claim the mean difference between instruments is significant. Autocorrelation makes the test invalid at the outset anyway.

So, while technical, statistical and boring, that is one reality of t-tests (and there are oodles of stuff on the internet about it, which dispels the need for opinions).

The next is whether platinum resistance probes and associated hardware (wires, loggers, comm-gear etc.) are affected by the many sources of electronic noise at airports, for which no-one actually seems to know or can present any hard-data one way of the other. Aeroplanes are full of sensors including PRT-probes, so if there is a problem with interference, it stands to reason that it would have been solved by now.

Nevertheless, the proof is in the pudding, which is whether maximum temperatures measured using thermometers verses those measured by automatic weather stations in the same screen are different, for which Jennifer has not released her datasets.

[Previously I reported that when day-of-year cycles were deducted from Halls Creek Tmax, the small difference detected by the paired t-test of raw data (AWS minus thermometer data), was no longer significant. I also analysed and graphed high-frequency (1-minute data) for Bundaberg and maximum and minimum Tmax within 6-minute or 0.1 hourly intervals. Data showed rapid heat exchanges during the heat of the day and other things going-on around dawn, which probably related to evaporation of dew and rapid changes in relative humidity for which no data was available.]

The third issue is Graham Readfearn, who apparently lives in Brisbane with a few backyard chooks and also writes BS for The Guardian.

This is the weak-spot, but while attention is focused on the significance of differences that are too small to matter, and whether AWS are affected by hand-driers, Teslas, microwaves and baggage handlers at airports, corruption of the Bureau’s processes, for which there is unequivocal evidence, flies completely under the radar (pun intended).

It takes no time at all to toss some data into Minitab or Excel, do a paired t-test and ignoring basic assumptions get the The Australian sufficiently excited to write an article about it. However, it takes months to carefully research a weather station and draw the evidence together which shows that scientists at the Bureau, most recently Dr Blair Trewin have cheated the data on which everything else, including Graham Readfearn at the Guardian, and Peter Hannam and his ilk at the Age and Sydney Morning Herald, depend. They are marketeers of fake news.

The whole warming-thing is unequivocally fake, and it’s been faked since homogenisation started around 1990. Yet that message is constantly subsumed by little things that even if ‘proved’ really do not matter.

Thanks for reminding me there is a downside to resorting to satire, hard-line and even condescending commentary to make that point. .

Yours sincerely,

Dr Bill Johnston
http://www.bomwatch.com.au

Reply to  Bill Johnston
May 12, 2023 4:59 pm

Bill. Just making stuff up again? If you had really checked the history like i did you would know what was there and when and be able to get the BoM to correct some errors.

But Jenifer the site was not run by the Bureau, it was run by the Botanic Gardens people, who also pruned the roses and moved the sprinklers …”

The site 040214 was not ever there at all. Prove me wrong.

Reply to  siliggy
May 12, 2023 6:10 pm

Hi Lance, glad to see you are up and about,
 
Actually, I’m just channeling Jennifer, who said “It is interesting that before the Airport became the official site for reporting Brisbane temperatures, temperatures were recorded in the Botanical Gardens (Station No. 040214)” and “according to the metadata for that station, there was only one mercury thermometer installed on 1 January 1840 and removed on 1 July 1994, when the station was closed”
(https://wattsupwiththat.com/2023/05/11/jokers-and-temperature-as-radio-chatter/#comment-3720238).
 
While the coordinates land the Google Earth Pro pin in the Botanical Gardens (Latitude -27.4778, Longitude 153.0306) close to the Gardens Club (probably the old observatory), I just don’t know who or what to believe – Jennifer or you at this stage.
 
Just for the record, while they probably have a stack of paper files Simon Torok said:
 
Brisbane 40223 and 40214
07/1896: Glaisher stand replaced by Stevenson Screen
07/1911: New screen
12/1915: New screen
01/1950: Move for composite site
 
Torok also homogenised 40223 data (Brisbane Aero with 40214 (Brisbane RO (wherever it was)) to 1993, whereas ACORN-SAT only starts in 1949. Odd that.

 
Yours sincerely,

Bill

Reply to  Bill Johnston
May 12, 2023 9:19 pm

OK Bill. Lets see if i have this right. You don’t know who to copy or where it was and this is why you name call? Need to do your own research for real but try instead to harass someone else into feeding you the info. Yet somehow you think you know who looked after it.

Reply to  siliggy
May 12, 2023 10:25 pm

No, you do not have it right Lance.

You said: “Bill. Just making stuff up again? If you had really checked the history like i did you would know what was there and when and be able to get the BoM to correct some errors.”

If 40214 was the site, it was at the Botanic gardens, miles from the RO in Anne Street. It is unlikely they would be running backwards and forwards every three hours to do observations.

Anyway, I was quoting Jennifer; she mentioned the BotGar site and said there were thermometers there (Station No. 040214). That was news to me.

I had previously had a cursory look at Brisbane RO data and undertaken some basic internet searches in January 2018 and August 2020. Thus I knew about the old windmill observatory and the Botanic Gardens site, which if you look at the Lat Longs, is in the same place as where the BoM said in the station list, was the position of the Brisbane RO site. (Confused yet?, you and me both!) When I replied to you, I had also cross-checked using Google Earth Pro. I also gave you Simon Toroks’ take on the site and he also talks about 20214 as the “Brisbane” site

You think I don’t do my own research; that I want you feed me the info; and karlomonte wonders why I get impatient etc. and then thinks I should apologise for reacting to being driven to distraction.

The question is: with you and Jennifer talking authoritatively about it, why hasn’t the problem of locating the Brisbane RO site (if it was 40214) been solved by now? Or has it been?

The other question is, why have they not homognised Brisbane RO (40214) with Brisbane airport data, when those stations were homogenised previously by Simon Torok?

While I don’t want you to feed me any info,, certainly not bad info, they are questions worth considering.

(To clear the fog, I also summarised what I think the main threads of this post are about (https://wattsupwiththat.com/2023/05/11/jokers-and-temperature-as-radio-chatter/#comment-3720530), .

All the best,

Bill

Reply to  Bill Johnston
May 12, 2023 8:58 pm

I’m not the person to whom you should be apologizing.

Reply to  karlomonte
May 13, 2023 3:28 am

Dear karlomonte,

Just for the record, issues of statistics, tests, metadata, Stevenson screens, iron legs, radars, PET-probes and electronic whisperers have been on-going for the best part of a decade.

Unfortunately, in all fields and in almost every train-carriage, school and office, reason gets trumped by tribalism which undermines, supplants and destroys common purposes.Yelling louder or more persistently is not the same as providing a well-researched, unassailable, dependable and considered view, which I believe is where this process has come-off the rails.

Unbeknown to you, at the outset of my involvement with JM and others, I set-out to personally meet and engage with most players. I traveled to Western Australia; also met with Jennifer and John Abbott in Sydney, Lance and Warwick in Canberra, and also with Lance several times as a guest my home. All are articulate, decent and well-meaning people.

However, time is short and for a decade the curse of little things that make no difference continues to bog us down at a time when we should be years in front.

While I am served-up as the bunny for that, careful research reported at http://www.bomwatch.com.au has unequivocally exposed malfeasance by high-ranking scientists and leaders and directors within the Bureau of Meteorology at a scale that is breathtaking. Manipulating data to support political narratives destroys public trust. CSIRO, the Australian Academy of Science and other institutions are deeply compromised.

For her part, Jennifer has has made exceptional claims, but except for opinion-based or Excel-level science, she has not done this. While loudness is good, an unequivocal stick-on message is much better.

While socking it up Graham Readfearn and his chooks may generate booby-prizes, scoring two wins with the same bet (Readfearn AND pull-along toys like Peter Hannam) would demand respect. But despite years flowing-by, this has not happened.

While I have dealt with many of these issues over-and-over here on WUWT and at Jo Nova, and in emails and discussions, no-one, least of all Jennifer has ever said “Oh, thanks Bill, I get that”, and moved on. Instead they ignore and re-cycle. In the meantime, orchestrated by the loudest noise, we (you and I) tread-water.

How would this work in your tennis club, chess-group or any other place? My unpaid time is precious and as a member of the IPA, who contributes salary to Jennifer and husband John Abbott, while continually asked to contribute more, is it they who need to lift their game. We (members) depend on them (whom we pay) to deliver trustworthy messages.

Put simply, after all this time and irrespective of the gender-card, Jennifer’s position should be unassailable by Readfearn’s chooks and cronies. If not, why not?

Not having the ducks lined-up and with Lance coming in from the side, a stand-alone situation occured that should not have depended on my silence. On that basis, while I regret expressing my frustration in such strong and personal terms, I won’t apologise.

Readfearn is empowered by cheque-waving circumvent the truth, pay me back later political dullards. Malcom Turnbull and his little boy Alex leaps to mind.

However Readfearn’s chook-shitty, one-side reporting HAS TO STOP.

With that in mind, I have provided position statements here and previously, that in my view are sufficient under the circumstances.

Yours sincerely,

Dr Bill Johnston

http://www.bomwatch.com.au

Reply to  Jennifer Marohasy
May 12, 2023 4:31 pm

Hi Jennifer only a month ago i posted this comment on your “bureau-releases-limited-parallel-data-from-brisbane-airport” Post. You replied “Thank you Lance. This is important information. You had already mentioned it to me. But I had forgotten.”

That site info “metadata” you have for Brisbane site 040214 is not the most recent. In 2019 i emailed them with a few questions about the accuracy of that location.
Here is the reply.
“Dear Lance,
Thank you for your emails which highlighted errors with the location of these two weather stations. The co-ordinates for these sites have been corrected internally to reflect the estimated location for each.
The correct Brisbane Botanical Gardens (040215) location is -27.4778, 153.0306. Note that this site was a rainfall site only, there was never any temperature measuring equipment at this site.
The Brisbane Regional Office (040214) location history is a little more complicated as there ​were some site moves, but the last location for this site before it closed is estimated to be -27.466, 153.027.
The metadata files available online are only updated once a year at the start of the Financial Year, so these updated locations will be reflected in those files from sometime after July 2019.
Regards,
Climate Data Services
Bureau of Meteorology”
While they say “There was never any temperature measuring equipment at this site”, i looked into it a bit more and found that Clement Wragge had a Stevenson there for a couple of years after 1890 but he seems to have closed it well before the BoM were ever involved.
Lance Pidgeon.

Reply to  siliggy
May 12, 2023 9:06 pm

Dear Lance,

I have an old list archived in 2014, of all known original Lats and Longs for the BoM’s weather stations (properties say it was a text file created on 9 July 2020, and I think I found it on one of the BoMs then accessible directories).

Coordinates for Brisbane Botanical were -27.4833 153.0333 and for Brisbane RO, -27.4778, 153.0306. Which of these sounds like -27.4660, 153.0270 (current meta for RO), or -27.4778, 153.0306 (current meta Brisbane Botanic)? Then of course there is the old windmill observatory and signal station, with its flagstaff and time-ball, where they also probably undertook weather observations (https://www.slq.qld.gov.au/mappingfuturebrisbane/old-windmill-tower).

Perhaps they are simply very confused!

(If you asked nicely I could send you and Jennifer the list.)

All the best,

Bill

Rud Istvan
May 11, 2023 2:40 pm

There are many ways to show the surface temperature record is not fit for climate purpose. Jenn’s posts are but one. Dozens of others were outlined in essay ‘When Data Isn’t’ in ebook Blowing Smoke.

I know of no ways to show that it might be made so via ‘adjustments’.

Reply to  Rud Istvan
May 11, 2023 2:47 pm

Thanks Rud. I am standing on the shoulders of giants, including Anthony Watts.

:-).

Reply to  Jennifer Marohasy
May 11, 2023 10:11 pm

That is an odd metaphor under the circumstances, I stand on my own two feet!

Cheers,

Bill

Reply to  Rud Istvan
May 11, 2023 3:49 pm

“not fit for climate purpose”

You and Jenn may want to look at “A Comparison of Daily Temperature Averaging Methods: Spatial Variability and Recent Change for the CONUS” by Jase Bernhardt.

The kludge of using (Tmax+Tmin) has *always* been biased because of the different temperature profiles between daytime and nighttime. That difference results in a statistically significant skew in the daily temperature profile (typically toward night) that just can be recognized using a mid-range value by itself.

Why climate science has refused to move to integrating the entire temperature profile instead of stubbornly sticking to the mid-range value is just beyond me. The data has been available since at least the 80’s, i.e. 40 years or more. If it had been recorded and properly analyzed we would have *much* better views of what is happening with the climate.

Reply to  Tim Gorman
May 12, 2023 4:09 am

I would say we should just go with Tmax, which shows the warmest temperatures, and the highest temperatures are the most important part of this human-caused climate change meme, so let’s compare high temperatures in the past with high temperatures today. And the written temperature records go back more than 40 years.

What we will see is that it was just as warm in the Early Twentieth Century as it is today.

And, since there is much more CO2 in the atmosphere today, than there was in the Early Twentieth Century, yet it is no warmer today than then, this demonstrates that CO2 increases have had little effect on the temperatures.

Here’s a Tmax chart for Australia:

comment image?
resize=640%2C542

Reply to  Tom Abbott
May 12, 2023 4:49 am

Tmin is important for a lot of reasons. It is the primary determining factor in growing season length, snow melt in spring, etc. Both need to be tracked, just for different reasons.

Mr.
May 11, 2023 2:42 pm

Nowadays, the Bureau takes temperature readings every one second from what are called resistance probes and the very hottest of these instantaneous values is designated the maximum temperature for that day.

Jennifer, I asked this in comments on your last post here, but didn’t get any answers –

Is this function an automated process (ie hard-wired into the equipment), or a programmable function that the equipment installers / operators can customise?

?

Reply to  Mr.
May 11, 2023 2:45 pm

Thanks Mr. It is a wholly programmable function that the installers can and do customise.

And the Director at the Bureau, Andrew Johnston, also boasts that the design of the resistance probe is ‘custom’.

:-).

Mr.
Reply to  Jennifer Marohasy
May 11, 2023 4:47 pm

OK, so is EVERY probe programmed exactly the same by the one instruction set, or can particular probes be ‘tweaked’ differently?

Reply to  Mr.
May 11, 2023 5:56 pm

Mr.

It is actually not that easy to calibrate these probes, and there are at least four different types of probes. But for sure they can be calibrated to record hotter or cooler than a mercury and more. Then they drift, and need to be recalibrated.

:-).

I’ve written so much about the issue of numerical averaging, or not. That is a calibration issue.

They can even be programmed by way of a special card to not record temperatures below a particular set limit. Remember for 20 years at Goulburn there was a limit of -10.4C set on how cold temperatures could be recorded.

I’ve written at length about that, including here: https://jennifermarohasy.com/2017/09/john-plus-10-degrees-bureau-loses-minus-10-degrees/

:-).

Mr.
Reply to  Jennifer Marohasy
May 11, 2023 6:18 pm

Thanks Jennifer.
I do remember the minus 10 limiting parameter setting.

Can’t say I’m gaining confidence in all this “hi-tech” temp recording shenanigans the more I find out.

Reply to  Jennifer Marohasy
May 11, 2023 8:01 pm

Custom? I’m reminded of the old joke about the US analog television standard, NTSC. The joke was that it was an acronym for Never Twice the Same Color.

Reply to  Mr.
May 12, 2023 6:05 am

Not sure how BOM works, but here is some info on ASOS in the U.S.

“””””Both ambient temperature and dew point temperature are considered conservative elements (i.e., continuous in space, and slowly and smoothly changing in time). Based on this characteristic, time-averaging over a short period is the preferred method of measurement. “””””

“””””The ASOS hygrothermometer continually measures the ambient temperature and dew point temperature and provides sample values approximately six times per minute. Processing algorithms in the hygrothermometer use these samples to determine a 1-minute average temperature and dew point valid for a 60-second period ending at M+00. These data are passed to the ACU for further processing.”””””

“””””Once each minute the ACU (Acquisition Control Unit) calculates the 5-minute average ambient temperature and dew point temperature from the 1-minute average observations (provided at least 4 valid 1-minute averages are available). These 5-minute averages are rounded to the nearest degree Fahrenheit, converted to the nearest 0.1 degree Celsius, and reported once each minute as the 5-minute average ambient and dew point temperatures. All mid-point temperature values are rounded up (e.g., +3.5°F rounds up to +4.0°F; -3.5°F rounds up to 3.0°F; while -3.6 °F rounds to -4.0 °F).”””””

Mr.
Reply to  Jim Gorman
May 12, 2023 6:46 am

Thank you Jim.
Very informative.

Bob
May 11, 2023 3:04 pm

For the life of me I can’t think of anything the government has done that we can all be proud of. I’m sure there is probably something but they are so incompetent that any good is hard to find.

Rud Istvan
Reply to  Bob
May 11, 2023 3:44 pm

In the US there was at least one. The original EPA charter to clean up real pollution was successful. It finished up about 20 years ago. Unfortunately, the EPA bureaucracy did not then sunset, and now does much real damage via linear no threshhold and CO2 as a pollutant.

Bob
Reply to  Rud Istvan
May 11, 2023 4:22 pm

I understand where you are coming from Rud but even when they have done something good they can’t let go of it until they have destroyed it. It is so frustrating.

Mr.
Reply to  Bob
May 11, 2023 4:54 pm

Exactly.
My conclusion after a lifetime of observations of human “good intentions” endeavors is that they always swing too far in one direction initially, and then too far back in the opposite direction, rinse & repeat ad nauseam.

The pendulum takes generations to come to rest, often with more downswings than upswings over the whole course of the movements.

We never turn out to be as smart as we thought we were when we first embarked on activating our “remedies”.

Reply to  Mr.
May 12, 2023 9:54 am

But we spent a lot of tax dollars and employed a lot of people making checkmarks on forms that got filed away and can’t be found.

sherro01
Reply to  Rud Istvan
May 11, 2023 9:09 pm

Rud,
Have you ever seen an analysis of the success of the US EPA, in the sense that corporations did a lot of cleanup without EPA having to tell them?
In the real world in which I worked after our EPA started “enforcement”, (Australian mining), industry knew much more about how, why and when to remediate than EPA did. There were many cases where industry was planning and doing rehab as the money became available. Maybe the EPA did damage by demanding immediate expenditure, taking money too soon from other deserving work.
I have never found high competence in our EPA. We took the State branch to Court once and won with costs after they demanded unrealistic rehab.
Question is, did US EPA achieve anything more than self-gratification?
Geoff S

Reply to  Rud Istvan
May 12, 2023 6:14 am

Typical bureaucracy, always find something “new” to accomplish in order to justify your continued existence.

Do you ever wonder why they do not establish local groups in the poor areas most affected by whatever problem they “discover”? It always requires travel of so-called experts from a central location! If bureaucrats had to relocate to affected locations, do you think the problem would long exist?

Sommer
May 11, 2023 3:20 pm

Someone sent this to me today to show how fear is stoked by the weather forecasters. Take a look at the visuals used.

wideawake_media (@Wide Awake Media) Tweeted: Look at how much hotter it’s gotten in just five years! https://s.w.org/images/core/emoji/14.0.0/svg/1f921.svg

It’s basically a scorched Earth at this point. https://s.w.org/images/core/emoji/14.0.0/svg/1f644.svg

#ClimateScam #ClimateCult #NetZero #Agenda21 #Agenda2030 https://twitter.com/wideawake_media/status/1656667554012876806?s=51&t=JQmXS6FtM8RkgF0lWwt4_A

old cocky
May 11, 2023 3:43 pm

I could ask why they used email (the multiple emails would be because of attachment size limits) rather than one of the secure file transfer providers such as dropbox or the Dept of Commerce’s facility, but I’m afraid I might receive an answer.

Reply to  old cocky
May 11, 2023 3:52 pm

Of course there are FTP drives, and Dropbox.

:-).

Nick Stokes
Reply to  old cocky
May 11, 2023 6:19 pm

I once in my CSIRO days (in 1980) BoM sent me a whole lot of recently digitised temperature and rainfall data. It came on a 8 inch floppy drive, fortunately compatible with our PDP11. I believed it cost about $20K, and it was my job to get it back to them safely.

leefor
Reply to  Nick Stokes
May 11, 2023 7:42 pm

And memory is now so much more expensive. 😉

old cocky
Reply to  Nick Stokes
May 11, 2023 8:26 pm

Ahh, the good old days 🙂

The 8″ floppy drives were a bit before my time, but we had a tape robot the length of a cottage full of 200 MB IBM 3480 tape cartridges for backups.
I used to have to call the operators to feed a set of them in one at a time to run some ad-hoc data extracts every week or two. We thought we’d died and gone to heaven when the company bought a headless SUN workstation and mirrored hard disks which could hold the complete (at that time) 5 years of data, and we could store the new logs in colon-delimited format instead of fixed-length fields.

Was that $20k 8-inch a floppy drive with a bunch of floppies, or one of the early 8-inch hard disks? They were pretty serious stuff back then.

A PDP-11. Luxury, for the time.

Mr.
Reply to  old cocky
May 11, 2023 10:11 pm

Looxury!.

We ‘ad abacus, only one between 15 of us, and fire in middle of road to send smoke signals.

And we were ‘appy.

But tell youngsters that these days, and they won’t believe ya . . .

old cocky
Reply to  Mr.
May 11, 2023 10:23 pm

No, they woan.

Reply to  Mr.
May 12, 2023 1:06 am

Yeah, but you could handle it like a man who grew up pushing his own pram…

Reply to  old cocky
May 12, 2023 6:31 am

Indeed a luxury. Our EE department thought it was in hog heaven with a PDP-8! Programmed it using front panel switches. No way to save your program, it had to be reentered everytime someone else used it. My first experience with magnetic core memory, but not the last. AT&T used a lot of that memory in their early Electronic Switching Systems. Even got to participate un-sewing and sewing new cores into a couple of units.

sherro01
Reply to  Jim Gorman
May 13, 2023 8:19 am

Jim.
The DEC PDP8i was my second small computer, after a Data General Nova. I bought them for data loggers in analytical chemistry labs. About 1968.
Yes, you actually had to set 8 toggle switches up or down, press enter, repeat with the next set of numbers, repeat about 20 times IIRC.
That was the boot to start it. Make one mistake, start from scratch again.
Then, the joy of storage on an ASR-33 paper tape punch. 10 characters per second.
All this was about 11 years before IBM released its first Personal Computer.
I marvel sometimes how naive some youngsters are with the latest PC and all those programs written by others. Statistics in particular are often used as a drunk uses a lamp post, more for support than for illumination.
Geoff S

Reply to  sherro01
May 13, 2023 8:49 am

Then, the joy of storage on an ASR-33 paper tape punch. 10 characters per second.

That was what we used to program our “2nd” generation Electronic Switching System machines. We had hundreds of rolled up tapes used for different things like line assignments, routing codes, etc.

The first ones used special “punch cards” kind of like the IBM punch cards. You had to punch them by hand, similar to the voting cards they used when the “hanging chad” arguments erupted here is Florida.

Izaak Walton
May 11, 2023 3:57 pm

Is there even the slightest bit of evidence for this:
A mercury thermometer is completely impervious to the beat of airport radar that may move across the tarmac every 30-40 seconds. Not so, what are referred to as ‘low noise’ amplifiers attempting to precisely measure the change in resistance of the platinum electrodes in the resistance probe: that is how the probes measures temperature. These electrodes may not only be energised every time the radar sweeps over them, but also by the chatter from a pilot in the airport’s control tower.”

And what exactly does energising an electrode actually mean? What would such a circuit look like? And even if there was radar interference it could be easily be sorted by putting the thermometer inside a Faraday cage.

old cocky
Reply to  Izaak Walton
May 11, 2023 4:03 pm

And even if there was radar interference it could be easily be sorted by putting the thermometer inside a Faraday cage.

It would be more likely to be the cable to the data logger acting as an antenna, but shielded cables are readily available.

Mr.
Reply to  old cocky
May 11, 2023 4:57 pm

shielded cables are readily available

Hard to buy anything else these days?

Reply to  old cocky
May 12, 2023 4:20 am

…but shielded cables…

…either grounded at both end, or cut short with the sleeve, because “it’s just there to protect the cable”?
I would not be surprised to discover Standard Operating Procedure is to do it the wrong way. Because, you know, global warming.
Also interference to the logger would probably register as bitstream faults, not observable temperature series.

Alexy Scherbakoff
Reply to  Izaak Walton
May 11, 2023 4:40 pm

I guess a metal box wouldn’t affect the temperature inside it.

old cocky
Reply to  Alexy Scherbakoff
May 11, 2023 4:57 pm

In Boulia or Bedourie? Yeah, nah!

Reply to  Alexy Scherbakoff
May 11, 2023 8:06 pm

It can be a porous screen, if the dimensions are chosen for the wavelength intended to be attenuated.

Alexy Scherbakoff
Reply to  Clyde Spencer
May 11, 2023 8:19 pm

I’m aware of that…. but still.

Reply to  Clyde Spencer
May 12, 2023 4:56 am

Considering the power level most airport radar units run at a porous shield may not be sufficient. The currents induced in the shielding itself from those high powered spikes can generate noise itself even across the small resistances seen in the shielding material. Look at the shielding required in just a small kitchen microwave – and they run several orders of magnitude less power than a high powered airport radar. If I get close to our microwave while its running I can hear noise in my hearing aids from the escaping power!

Reply to  Tim Gorman
May 12, 2023 10:05 am

I can hold up a window pane in front of an AM radio transmitter and hear the program. Been there, done that. RF radiation is everywhere.

Nick Stokes
Reply to  Izaak Walton
May 11, 2023 5:55 pm

And what exactly does energising an electrode actually mean?”

Yes, weird understanding of physics on display here. It is not of course an electrode, but a platinum resistance wire. It is not “energised”, and there is absolutely no reason to expect that it will be affected by radar or chatter.

Alexy Scherbakoff
Reply to  Nick Stokes
May 11, 2023 6:58 pm

Why don’t you go to a quarry and tell them it’s unnecessary to turn off radios. After all, the detonator has a little wire and won’t heat up due to radio waves.

Reply to  Alexy Scherbakoff
May 11, 2023 10:16 pm

They only do that so they can hear the bang, which tells them when it has gone off, silly!

Alexy Scherbakoff
Reply to  Nick Stokes
May 11, 2023 7:08 pm

How do you measure resistance without applying a voltage/current?

Reply to  Alexy Scherbakoff
May 12, 2023 6:57 am

Exactly.

Reply to  Nick Stokes
May 12, 2023 7:01 am

“””””Two, three, or four leads are connected to the element and are used to provide for the measurement of the electrical resistance of the element. Some of these characteristics are: “””””

“””””Wide temperature Range (–260°C to 1000°C)
Electrical resistance is typically between 0Ω and 400Ω and depends on temperature

Excitation current is typically 1mA

Stable over time
Stable over temperature
Shallow slope (i.e. 0.4Ω/°C for a 100Ω PRT)
Relatively easy to measure
Relatively easy to calibrate
Commercially available in many configurations

See the excitation current for a PRT? They are “energized”!

Reply to  Nick Stokes
May 12, 2023 10:09 am

As I recall, resistance equals voltage divided by current flow. If a wire is not “Energized” then you cannot measure resistance let alone a change in resistance. It is impossible by definition. This is basic stuff you are arguing against.

Reply to  doonman
May 12, 2023 6:28 pm

This is basic stuff you are arguing against.

Very basic. A constant current is supplied on one pair of wires and the other of the two pairs in the four wire system carries back the Voltage to a linearisation circuit. There is a trade off between Johnson noise =Root(4KTBR) and the sensor current. It seems none of the commentors here is mentioning that a resistor with a current flowing through it produces heat. This self heating needs to be allowed for by the data logger as it calculates the temperature. A greater sensor current means better signal to noise ratio but worse self heating compensation error as humidity and wind speed both change the required compensation.
To calculate this internal noise =root(4KTBR), K is the Boltzmann constant, B is the bandwidth that can pass on from the resistance and R is the resistance.

Reply to  Izaak Walton
May 11, 2023 6:54 pm

Hi Izaak et al.

I am happy to be corrected on this detail of the physics.

This is my understanding:

A platinum resistance thermometer (PRT) is a piece of platinum wire which determines the temperature by measuring its electrical resistance.

Electrical resistance​ is the resistance of the flow of electrons.

Think of an electrode as a bridge that forges a passageway for electrons to travel on. Electrons are zipping around the nucleus of an atom. Technically, they’re subatomic particles with a negative electric charge.

How would you best explain the mechanism?


Alexy Scherbakoff
Reply to  Jennifer Marohasy
May 11, 2023 7:11 pm

He has nothing to argue with except semantics. Electrode/ sensor are sometimes used interchangeably.

Izaak Walton
Reply to  Jennifer Marohasy
May 11, 2023 8:32 pm

Jennifer,
In any wire exposed to an external electric field there will be additional currents which will add noise. However such facts are well known and one of the first things that electronics students get taught is how to shield components from external fields. And certainly the smaller the effect is the more carefully you need to shield components from fields. So it might be possible that a microwave beam could change the reading of a platinum resistance thermometer but only if it was badly designed. So my question is if there any reason to think that such thermometers were so poorly designed that a transient radar beam would change the temperature reading? Similarly is there any evidence that there is significant energy from a radar installation at ground level given that they are looking for planes in the sky?

Again the combination of a well designed radar installation and a well designed PRT system means that any effect of the former on the later is going to be very small. And the effects of a pilot’s radio is going to be orders of magnitude smaller since the wavelength is longer and the power is lower.

old cocky
Reply to  Izaak Walton
May 11, 2023 9:13 pm

I think you’re right that the RADAR and radio chatter are unlikely to have much effect, and would stick out like a sore thumb.

There are other sources of electrical noise (see https://www.allaboutcircuits.com/technical-articles/electrical-noise-what-causes-noise-in-electrical-circuits/ https://en.wikipedia.org/wiki/Noise_(electronics)) which the EEs can probably expand on.

If sufficiently granular data is available, noise can be spotted quite readily by graphing an visual inspection, or sudden jumps can be detected readily enough computationally (absolute value of differences in consecutive values above a threshold)

Hopefully, the BoM has systems in place, but the high-frequenvy data doesn’t seem to be readily available.

Nick Stokes
Reply to  old cocky
May 11, 2023 10:54 pm

the high-frequency data”
Electrical noise is a red herring here. HF for data is about 1 Hz. Separating RF+ noise is very easy. Even 50Hz would count as high. And as for low freq noise, there is really no way it could enter the system; the EM wavelength is far too high.

old cocky
Reply to  Nick Stokes
May 11, 2023 11:12 pm

Sorry, that was bad wording on my part again. High frequency as in the highest sampling frequency that the Bom uses (1 Hz), but I don’t think that’s retained.

I don’t know enough about the instruments and data loggers to be able to say whether spikes can creep in. Major spikes would almost certainly be trapped, but without the 1sec data it would be difficult to validate.

Nick Stokes
Reply to  old cocky
May 12, 2023 2:22 am

They are not spikes. They are UHF oscillations, and should not get far in circuitry measuring 1Hz or so variations.

old cocky
Reply to  Nick Stokes
May 12, 2023 3:08 am

We seem to be thinking of different things. Electrical noise can cause spikes which could show up in the 1-second data..
1 Hz is 1 cycle per second, which is the data rate, not the noise rate (if it’s regular, it’s probably a hum rather than noise 🙂

Reply to  Nick Stokes
May 12, 2023 4:43 am

You really don’t know what you are talking about! A radar pulse is a high power pulse of very, *very* short duration. As an electromagnetic wave it affects *everything* it impinges on.

The safety regulations for working around high power microwave equipment are severe. You can actually be burned if you stick you hand in the waveguide carrying the amplified signal. Fringe affects can cause deterioration of eyesight over time.

The shielding that would be required to keep that high powered signal from impinging on the platinum probe as well as the electronic circuitry that reads the current through the probe and digitizes it would basically render the unit incapable of actually measuring the temperature surrounding the device.

This isn’t like noise generated from an electric fence charger or from a sparking commutator in a motor or 60hz hum from the power line.

I would agree that simple radio communications from the planes or tower would be unlikely to impact the measurement units *IF* proper shielding was done for the circuitry. But I am not aware of any design specs for temp measuring devices that specify what electronic shielding is required. Perhaps I just haven’t run onto such documents yet.

Reply to  Tim Gorman
May 12, 2023 6:05 am

I don’t think Nick understands that, after you filter out that frequency component he’s trying to sound knowledgeable about, you end up with the DC component, which is what would most likely come up as influenced readings. For airport RF noise to really add significantly to temperature readings, such a probe would have to be designed for such purpose in mind, which I doubt, but not discount.

Nick Stokes
Reply to  cilo
May 12, 2023 1:20 pm

 you end up with the DC component”
A DC component of E/M radiation?

Reply to  Nick Stokes
May 12, 2023 11:25 pm

🙂 Bored, Nick, or are you a team now, with shifts?
Yes, Nick, IF some mass absorbs the RF power and heats up, that would be called filtering out the AC and being left with the DC.
Also, Whittaker…

Reply to  Nick Stokes
May 12, 2023 7:13 am

Nick, the “pulses” are essentially square waves. Lots of harmonics involved. Why do you think the PEP wattage is so high compared to the average power?

Reply to  Nick Stokes
May 12, 2023 7:09 am

Have you done a Fourier analysis on a radar pulse? You have no idea what the harmonics are nor their power.

From the FAA;

“””””The transmitter generates a peak effective power of 25 kW and an average power of 2.1 kW. “””””

Quite a power level in each pulse of 25 kw. I’ll bet you wouldn’t want to look into the antenna up close.

Reply to  Jim Gorman
May 12, 2023 6:39 pm

While many of these signals are at very high frequencies they only need to find their way to a semiconductor they can vary through a non linear region to be “detected” into a DC offset..

Reply to  Izaak Walton
May 12, 2023 1:22 am

When dealing with high frequencies, voltages and/or currents, things can go odd in very odd ways. I can tell you some stories you won’t believe, and I could probably never replicate them for you. But let us look at an imaginary box sitting next to the runway:
The resistance probe will work by running current through some object (wire, pad, block) and registering the voltage drop across it. If you induce a current into the connection wires, this will not be measured, but the voltage difference will. Theoretically, your signal amplifier should reject such stray currents, because we assume the current hits both the wires, which we can cancel out easily, but I see and hear little evidence for design competencies. I shall not discuss the grade of “installation engineer” we hire off the street these days…
Secondly, extreme frequencies like radar may be absorbed by materials with unfortunate composition, raising the local heat component. I am not up to date on such research, beyond the point that stealth aircraft cost a lot to paint with such stuff. In the end, we would look at pieces of conductor juuust the right size to resonate, on which I shall not speculate here.
Thus I conclude: The possibility of RF interference exist, but unless you see very odd anomalies, I think the big problem remains stupid, willful and spiteful placing of stations, idiotic design (I have yet to see a station not surrounded by tarmac, even rural) and fraudulent reporting. Fraud.

Nick Stokes
Reply to  cilo
May 12, 2023 2:19 am

If you induce a current into the connection wires, this will not be measured, but the voltage difference will.”

It will be ac voltage in the range of many MHz. It would be the easiest thing to filter out from the 1Hz or so measuring frequency. I’m sure that it would not register in the detecting circuitry.

Reply to  Nick Stokes
May 12, 2023 4:47 am

Quite correct, the AC will be filtered out by the mass being warmed. Find out about envelopes. It is how you can build an AM radio with nothing but a few coils of wire and a dirty chrystal.

Reply to  cilo
May 12, 2023 5:16 am

How much of the circuitry in the measuring device uses balanced lines? E.g. the lead going from the voltage comparator to the digitizing integrated circuit? Or from the digitizing circuit to the summing circuit. And on and on.

Even balanced circuitry usually isn’t sufficiently balanced to cancel out the high power put out by a radar. If it was I wouldn’t hear noise in my hearing aids when I get close enough to a kitchen microwave.

Reply to  Tim Gorman
May 12, 2023 6:49 pm

the AC will be filtered out by the mass being warmed. “
Yep. A hot wire Barretter demodulator. They actually preceded the crystal set.

Reply to  Nick Stokes
May 12, 2023 5:13 am

Stop posting garbage about electronics that you obviously do not understand. I can guarantee you that *any* electronic circuit impinged upon by a high powered radar pulse will see effects from it.

Using your analogy lightning spikes shouldn’t induce “noise* into most anything electronic. Yet they do. They are very short pulses, just like a radar pulse. Doing a fourier analysis on a pulse like this will give you energy traces all over the spectrum, from DC to VHF.

Reply to  Tim Gorman
May 12, 2023 6:47 am

Grounding and shielding is not a trivial subject, and it is easy to make something way worse if you don’t know WTH you are doing. But as usual, Stokes is the world’s foremost expert on absolutely everything…

Reply to  karlomonte
May 12, 2023 10:24 am

Stokes poo-poos everything that affects measurement accuracy as inconsequential. But he is extremely concerned about the 0.0136 yearly increase of degrees of global average surface temperature anomaly.

Reply to  Nick Stokes
May 12, 2023 3:46 pm

You have no idea how the fundamental and harmonics will be presented on the sensor wire. And, I’ll bet you can find no experiments that attempt to measure what that radar could do to a solid state thermometer.

Reply to  cilo
May 12, 2023 6:44 pm

unless you see very odd anomalies”
You only see what you look for in data you can obtain. From some of that Jennifer reports: “all over the place” differences between the InGlass and .automatic temperatures.

Reply to  siliggy
May 12, 2023 11:31 pm

…which brings me to the one question I’ve been burning to ask:
With all this wonderful technology and precision and accuracy and once-a-minute-word-of-grod updates, why not just make the stations available on the internet, live, real time,’strue’s nannies no bull?
But then I remembered how, at the beginning of the warmunist climastrologist thermageddon, all public access to weather station data was abruptly cut off.
At least, that was what many a commenter from the US told us… Must admit I was never that interested, so I don’t know.

Reply to  Izaak Walton
May 12, 2023 6:52 am

You obviously have no experience with RF. A radar pulse is pretty much a square wave. Do a Fourier analysis on what harmonics are involved. The resistance wire CAN act as an antenna and have spurious currents generated in the wire. If the current is measured every second, there may be errors introduced. As to their magnitude, who knows without testing.

Richard M
May 11, 2023 8:05 pm

I thought that was a picture of Al Gore in too much makeup.

Keith.
May 11, 2023 11:32 pm

Bard appeared in my email, and for amusement I asked “Are platinum electrodes as accurate as mercury/alcohol thermometers in measuring ground temperature ?”
Reply:
Platinum electrodes are more accurate than mercury/alcohol thermometers in measuring ground temperature. Platinum electrodes are made of a material that has a very low coefficient of thermal expansion, which means that they do not change size very much as they heat up or cool down. This makes them very accurate for measuring small changes in temperature. Mercury/alcohol thermometers, on the other hand, are made of materials that have a higher coefficient of thermal expansion, which means that they change size more as they heat up or cool down. This can lead to errors in their measurements, especially when measuring small changes in temperature.
In addition, platinum electrodes are more durable than mercury/alcohol thermometers. They are less likely to break or crack, which can also lead to errors in their measurements.

I don’t know if the coefficient of thermal expansion has any bearing on accuracy, and, I did get three drafts that did not differ much…..so, that is Bard.

May 12, 2023 12:01 am

Ken Stewart does shorter posts, and gets to good finds shared by Lance Pidgeon a bit before me. :-).

https://kenskingdom.wordpress.com/2023/05/12/whos-laughing-now/

May 12, 2023 4:38 am

I have some perspective that in my observation, most people debating this topic have missed or are unaware of. That is airport weather stations, which do much more than read temperature, they read dewpoint, pressure, wind direction and speed, and some even incorporate visibility and cloud base altitudes.

These are critical safety issues for aircraft, especially for takeoff and landing functions. As such, the longest and most accurate records of weather parameters are found at airport stations. (if they were not accurate there would be more crashes and accidents)

It is imperative for the pilots of a modern airliner to calculate and determine the takeoff or landing speeds and distance required based on the immediate weather conditions of temperature, pressure and wind speed and direction. Hence these stations are located out in the airfield, often between runways and taxiways. The actual conditions on the runway is what is important for aviation safety. (and it is the character and quality of the air which provides the lift for wings to “fly” and in addition, these parameters are gauged against the weight and balance of the aircraft as well; and also noise restrictions, and on and on)

That these readings are sometimes artificially high compared to the actual air conditions away from these airfields is irrelevant to aviation safety.

So stop knocking aviation weather data, it has an extremely important purpose, and the stations tasked with this are indeed fit for purpose. What they are NOT fit for, is general weather and climate reporting, because they are located near runways and taxiways with a large heat island effect. (but the wings are attempting to fly in these heat island conditions, hence the actual conditions on the runway is what is paramount to safe flight)

Second the notion that aviation radar or even more ridiculous aviation communication transmissions affect electronic temperature probes to any significant degree is absurd in the extreme! I am both a pilot and worked in a lab with all manner of experimental set ups, many of which involved calorimetry. I’ve used IR probes, thermisters, thermocouples, RTD, etc. Many of the experiments we conducted were in extremely noisy RF conditions, even including near spark gaps. The notion that properly designed and certified temperature probes and measuring instrumentation is subject error due to radar and aviation comm frequencies is nonsense!

All of the electronic methods (thermocouples, thermisters, RTD etc) work in milli or micro volt regions at the sensing elements. As such serious shielding and nulling circuitry to reject RF noise are part of the instrumentation, else they could not work at all.

These kinds of temperature sensing elements and circuits are used in all manner of critical applications that are noisy, and function just fine thank you.

You are barking up the wrong tree with aviation weather data, and electronic temperature sensing as being the root of the problem of general weather/climate analyses.

Now, I do agree that the climate cult narrative has and is fudging the numbers. You need look no further than Tony Heller’s comparisons of actual raw readings vs the “adjusted” data and plotting the official adjustment delta against CO2 concentration shows a straight line. (image attached) This definitively shows they are adjusting the data to fit the theory which is not “scientific” it is propaganda and lying.

However, aviation weather stations are not the problem, they are necessary for aviation safety. They are not fit for general weather and climate purposes though – on that I generally agree but not for the reasons this article posits.

USHCN-FINAL-MINUS-RAW-TAVG-Vs-CO2-1900-2020-At-All-US-Historical-Climatology-Network-Stations-USHCN-FINAL-MINUS-RAW-TAVG-vs-CO2-1.png
Reply to  D Boss
May 12, 2023 5:23 am

Second the notion that aviation radar or even more ridiculous aviation communication transmissions affect electronic temperature probes to any significant degree is absurd in the extreme!”

Sorry, you’ve never worked with *high* powered microwave equipment. It is not only dangerous but can cause effects you simply can’t imagine in surrounding equipment or even near-field equipment. If this didn’t happen your kitchen microwave wouldn’t need to be shielded as much as it obviously is.

Reply to  D Boss
May 12, 2023 5:34 am

Appreciate your passion. By the end of this thread, may knowledgeable people such as yourself will have supplied enough information from enough perspectives, so all will know the limits of the stated theory. This may seem trivial, but remember, this community tries to argue with
a bunch of twerps who love to quote by the millidegree, so we have to consider every millidegree.We appreciate that those runway metrics are doing the job required, we merely contend that the only other purpose they serve, is to scare the bejeezus out of illiterates.

And boy, can RF play havoc with reality…

Reply to  D Boss
May 12, 2023 7:57 am

I sincerely doubt your spark gap experience used 25 kw PEP power levels. Remember, radar also concentrates this power with directional antennas

Plus spark gap transmitters have been outlawed internationally since the early 20th century due to the broadband noise they generate.

.

May 12, 2023 8:20 am

Most Pt RTDs are not calibrated; in lieu of individual calibration, sensor manufacturers rely on standard resistance versus temperature tolerance curves (see example below). Sensors can be trimmed during manufacturing so that the resistance falls within the various tolerance bands. The tolerance bands introduce temperature measurement uncertainty (that varies with temperature), but in the majority of applications this uncertainty can be ignored.

https://www.omega.com/en-us/resources/rtd-hub

100 ohm RTDs.jpg
Reply to  karlomonte
May 12, 2023 11:43 pm

Soooo….these things were actually conceived to measure hundreds of degrees, and the meteorologists use the bottom 4% of the scale, with inverted results below zero?
Absofarkinlutely beautiful!

Nick Stokes
Reply to  cilo
May 13, 2023 1:46 am

Those are tolerance values. They are narrowest near 0C because that is where it matters most. There is no inversion.

Reply to  Nick Stokes
May 13, 2023 2:07 am

While it seems I owe an apology for not seeing just how useless a graph that actually is, the argument stands: Pt probes are by far not the most appropriate instrument to measure habitat temperature by, the range is ridiculous (and apparently not very precise).
May I guess the reason it is used, is because of the libtard preoccupation with glittery things?
Think of Homer Simpson drooling:
“Hmm…Platinum Probes, niyarmmm….”
Alternately think of St. Gretha going:
“Mercury in the firmommeters? MERCURY!!!?”

Reply to  cilo
May 13, 2023 6:53 am

Below 0°C the tolerances increase with decreasing T, and note that the tolerances are specified as plus-or-minus, which means that the direction of the measured temperature error is unknown. For a Class B RTD, the error at both +40°C and -40°C can be as high as ±0.7°C.

Reply to  karlomonte
May 13, 2023 7:10 am

Which, again, raises the issue of how the global average temperature can be calculated out to the hundredths digit. Unless the uncertainty of the actual measurements are less than +/-0.005C then you have no idea what the value of .0x really is!

Reply to  Tim Gorman
May 13, 2023 10:19 am

Exactly right, and the tolerance uncertainty isn’t one that can be swept under the carpet with “all errors are random and cancel.”

Reply to  Nick Stokes
May 13, 2023 6:44 am

Again you reveal your ignorance…