This year the Australian Bureau of Meteorology waited until after close of business on Friday 6th January 2023 to release the official climate statistics for 2022. After claims of unprecedented extreme rainfall all year, the statistics must be disappointing for those animated by the idea of a climate catastrophe:
Nationally averaged rainfall was [just] 25% above the 1961–1990 average at 582.2 mm, which makes 2022 [only] the ninth wettest on record for Australia.
It is the sixth wettest year for Eastern Australia, where there had been extensive flooding.
Flooding that the Climate Council relentlessly blamed through 2022 on climate change. The Council is headed by Tim Flannery who at the end of April 2007, when most of Australia remained in the grip of severe drought, hyped global warming by claiming our dams would never fill again. Last year they filled to overflowing – again.
Eastern Australia, situated to the immediate west of the southern Pacific Ocean, has always experienced cycles of drought or flood depending on the El Nino-Southern Oscillation which modulates global temperature and rainfall.
Farmers like my father always linked this cycle to changes in the declination of the Moon and there are now research papers explaining the phenomenon. For example, Jialin Lin & Taotao Qian’s ‘Switch Between El Nino and La Nina is Caused by Subsurface Ocean Waves Likely Driven by Lunar Tidal Forcing’ published in 2019 by Nature.
Wet years are usually cooler years in Australia though the BoM claims last year to have been 0.5 °C warmer than the 1961–1990 average. In fact, discounting for the new electronic probes platinum-resistance probes* that I have shown can record 0.4 °C warmer for the same weather and the industrial scale remodelling (the technical term is homogenisation) that strips away past cycles of warming and cooling to the extent that past temperatures are artificially cooled relative to the present, sometimes by almost 3.0 °C (yes that much!) – in reality, last year is likely to have been on average much cooler.
But what about the rainfall statistics? Are all 697 rainfall stations spread across the land mass of Australia actually used to calculate Australia’s average rainfall, and how reliable are the new electronic rainfall gauges?
According to the BoM’s newly released 2022 statistics, the wettest year on record for Eastern Australia is still officially 1950 with 1021 mm, followed by 2010 (1012 mm), then 1956 (986 mm). The 1970s were also wet, especially 1974 with 960 mm, and 1973 with 853 mm.
The official rainfall total for Eastern Australia, where there was so much flooding through 2022, is 819 mms – much less than I expected.
There had been images on television of families huddled on the roofs of homes in Lismore on the morning of 28th February 2022. Waters rose, first entering backdoors, then filling living rooms, then forcing families to hitch each other onto rooftops. Surely the rainfall in places like Lismore was unprecedented?
Many of the submissions to the NSW Flood Inquiry from the Lismore community blamed the new highway built across the floodplain, not the rain, for all the flooding. They explain that the highway acted as a dam stopping water from flowing away and downstream.
Official reports blamed global warming, and either incorrectly reported the 24-hour rainfall total for Lismore (they published 146 mm which is the total for the 24-hours to 24th February, not 28th February 2022) or the reports ignore this important statistic altogether because the official rainfall gauge in Lismore failed. Yes, failed on 28th February 2022. And the Bureau has failed to acknowledge anywhere that there were no measurements from this official rainfall gauge in Lismore from 27th February through until 22nd July 2022.
The Bureau has also failed to acknowledge that there is data available from an alternative rainfall gauge in Dawson Street Lismore that recorded 467 mm to 9am on 28th February. This record only exists as a screenshot taken by a concerned citizen reposted at my blog on 23rd August 2022.
What should be acknowledged as a new 24-hour rainfall record for Lismore of 467 mm on 28th February has not been entered into any of the official reports or into the official Australian Data Archive for Meteorology. It presumably is not therefore part of the data used to decide that 2022 was (only) the ninth wettest on record for Australia.
There was a Special Climate Statement 76 – Extreme rainfall and flooding in south-eastern Queensland and eastern New South Wales published by the BoM on 25th May 2022 replete with regional distribution maps of rainfall across broad geographic bands and with intervals of varying quantity, with the highest value of 200 mm to an unknown total amount (pg. 5). It claims that there has been an increasing trend in extreme hourly rainfall (pg.18) but no actual data is provided – the reference is to State of the Climate 2020. I’ve also been through that report. It provides no actual observational data, nor does it cite any peer-reviewed study.
There is no mention of the reliability of any of the data – temperature or rainfall – by the Climate Council. It can only be concluded that they care more about the narrative. A narrative that is intentionally about blame and frightening especially women and children into action. It might give purpose to the lives of activists like Tim Flannery but at an enormous cost to our children, many of whom are now chronically anxious about the weather.
I was woken on Friday morning at 4am to the sound of rain. Not soft, steady rain. More like a herd of buffalo pounding across my tin roof – intense rain here in Yeppoon, to the east of Rockhampton and to the west of the South Pacific, a vast body of water that reaches about halfway around the Earth. As a child who grew up in the tropics on a farm to the south of Darwin in the Northern Territory of Australia, I used to be reassured by the drumbeating of that intense rain. It signified the beginning of the monsoon and the end of the bushfire season. Now children are being taught to fear something as natural as heavy rain in northern and eastern Australia. The messaging on television has been relentless: rainfall is more intense now – we have a climate emergency. Fear of rainfall is increasing in Australia that is one of the driest continents on Earth.
Climate activist Mali Poppy Cooper, 22, made national headlines when she locked herself to the steering wheel of her car on the approach to a Sydney Harbour tunnel to protest all the flooding in Lismore. Terrible flooding. She was bailed on condition she get psychiatric help. There are stories emerging now of children who experience panic attacks every time it rains.
All through 2022 there was reporting and storytelling, now incorporated into the school curriculum, about how the intensity of the rainfall has increased at Lismore and other locations. Never mind that the new automatic rainfall gauge at Lismore failed and that other gauges in the flood zone show no increase in rainfall intensity or volume when considering the historical record back to at least 1900.
Back in May 2022, Chris Gillham and I made a submission to the NSW Flood Inquiry showing that for the 20 longest rainfall records for locations in the 2022 flood zone there has been no overall increase in the intensity or frequency of extremely wet days to 2021. The wettest year, measured as the year with the highest number of 99th percentile rainfall days by volume since 1900, is still 1974.
We have updated this report** to include the daily rainfall values to the end of 2022 and an additional 5 locations. Our analysis combines data from days with extreme rainfall and compares values since 1900 and for 25 locations both within the flood zones and south to the Sydney region which did indeed record its highest annual total rainfall during 2022. There is still no general trend of increasing rainfall intensity, and therefore it is nonsense to blame climate change for the 2022 flooding. The year 1974 remains the year of most intense rainfall, which was also a year of above average cyclone activity including the infamous Cyclone Tracy.
It is not only a fact that the volume and intensity of rainfall is not increasing, but neither are the number or intensity of cyclones crossing the Australian coastline. They have in fact been in decline since at least 1979, the first year from which we have reliable satellite data.
It was very wet in southeast Queensland through 2022. I was in Brisbane on 3rd March 2022 helping with the clean-up after the devastating flooding of that city.
The Brisbane city flood gauge reached 3.85 metres on the morning of 28th February 2022. This exceeds the major flood level mark but falls short of the 1974 and 2011 floods which reached 5.45 metres and 4.46m, respectively. The Brisbane city flood gauge record goes back to 1832, with the highest flood being recorded in 1841. There was also flooding in 1873 and 1893. According to Aboriginal legend the Brisbane floodplain was not a place for building humpies, yet the European settlers who followed have built a whole city.
The flooding of Brisbane in 1974 was predictable in that the SOI index was an incredibly high 31.6 in November 1973, showing an extraordinary pressure gradient across the South Pacific as measured between Tahiti and Darwin. I was fearful of flooding in late 2010 as the SOI was again very high, 27.1 in December 2010.
After the floods of 1974 the Wivenhoe dam was constructed to ensure Brisbane never flooded again.
Despite the very high SOI and warnings from the mayors of some regional councils and farmers interested in long range weather forecasting and lunar cycles, the Wivenhoe reservoir upstream of Brisbane – built for flood mitigation – was kept full of water because it was believed by the authorities that the ‘dams would never fill again’ because of climate change. They had heard Tim Flannery. The dam operators kept Wivenhoe brimming with water as we entered the 2010-2011 summer despite the high SOI values.
When the torrential rain began to fall, as it always does, and because Wivenhoe was so full of water already, the flooding of January 2011 has officially been documented as a ‘dam release flood’ caused by the emergency release of water. This from a dam originally built for flood mitigation following devastating flooding in 1974. If water levels in Wivenhoe had been reduced through 2010, there would have been no climate emergency.
A class action brought against the Queensland government and one of the dam operators found they were negligent in the way the dam was managed and awarded compensation to those that had suffered loss as a result. But no money has yet been awarded, in part because of subsequent appeals.
During the worst of the flooding last year, in 2022, the dam operators again kept releasing water causing the city of Brisbane to flood. However, this time the torrential rain had stopped. Water kept being released because the BoM incorrectly forecast that more – even worse – rain was imminent. Rain that never eventuated. Now the mantra is that it just keeps raining and the dams will inevitably overflow.
I have benchmarked the skill of the BoM’s simulation modelling for seasonal rainfall forecasting in a series of papers with John Abbot. Our research papers, published in international peer-reviewed journals, as conference papers and book chapters from 2012 to 2017, show that the rainfall forecasting methods developed over a period of 20 years by the BoM provide no significant improvement in forecast skill beyond just simply calculating a long-term average rainfall for the period in question. This is despite spending hundreds of millions of dollars on expensive computers and models that attempt to replicate atmospheric processes.
There are much better methods for seasonal rainfall forecasting that use statistical modelling coupled with the latest advances in machine learning. This is a method that John Abbot and I pioneered and that is detailed in those same scientific papers. The first of these papers was rejected by the BoM’s own publication series in 2012, but accepted and published by the Chinese Academy of Science (Advances in Atmospheric Sciences, Volume 29, Number 4, entitled ‘Application of Artificial Neural Networks to Rainfall Forecasting in Queensland, Australia’).
While the SOI was very high during December 2010, and thus the extreme rainfall of January 2011 easily forecast, the SOI was only 13.8 during December 2021. It was thus not at all obvious to those interested in pressure patterns across the Pacific Ocean as an indicator of seasonal rainfall that we should expect flooding.
The flooding through 2022 was likely exacerbated by an atmosphere exceptionally high in volcanic aerosols from the explosion of the Hunga Tonga-Hunga Ha’apai volcano a month earlier. If the BoM had been tracking volcanic ash from that volcano and using a more reliable system of rainfall forecasting, and there was better town planning with the new highway through Lismore built on piers to let the water flow under the road and across the floodplain, there may have never been the tragedy at Lismore.
Exceptionally high rainfall totals in Hong Kong in 1982 correlate with the arrival of stratospheric aerosol plumes from the eruption of El Chichon in Mexico. Atmospheres high in aerosols can contribute to exceptionally high rainfall, but this is ignored by mainstream climate scientists including meteorologists at the BoM who continue to run simulation models inventing a role for carbon dioxide.
El Chinon was a large volcanic eruption, reaching 31 kms (19 miles) into the atmosphere. Mt Pinatubo that erupted in the Philippines in 1991 was larger, reaching 40 kms (25 miles) and causing surface cooling in the Northern Hemisphere of up to 0.6°C. The eruption of Hunga Tonga in the South Pacific on 15th January 2022 was even larger, reaching 57 kms (35 miles). Yet the BoM continues to deny it has had any effect on temperatures in the Southern Hemisphere. And the Climate Council would be hard pressed to blame us for explosive volcanic activity.
The aerosol plume from Hunga-Tonga travelled west, reaching Australia on 18th January 2022. Flooding followed with main railway lines and roads in central Australia washed away. By February 15th, the volcanic ash had circled the Earth and was back over Australia, evidenced by unusually intense sunsets. After that, it began to rain so intensely that Brisbane flooded – again, and so I was part of the clean-up on 3rd March 2022.
That afternoon a group of us working in Sandford Street, St Lucia, were told to down tools at 2pm. The BoM was announcing on radio that our situation was ‘dangerous’ and ‘potentially life threatening’. All the while the sun kept shining. Not a drop of rain fell from the sky and the waters of the Brisbane River below continued to recede.
As I drove out of Brisbane a few hours later, the flash flooding forecast for that same afternoon was cancelled. Next, on radio there was talk of the climate emergency and the scary ‘rain bombs’ of five days earlier. How it was all ‘unprecedented’ – the volume and intensity of rainfall. More than one metre of rain had fallen at some locations in just a few days.
The rain that fell in Brisbane was not unprecedented, neither in volume or intensity. Back in February 1893 nearly two metres of rain had fallen over a similar period of time at Crohamhurst just to the north of Brisbane. And there was no mention of the 24-hour record of 907mm, the amount of rain that fell at Crohamhurst on 3rd February 1893. This remains the highest 24-hour rainfall total for anywhere in Australia and it was 130 years ago. That rainfall recording station has since been closed.
There was also no mention on the radio of the Hunga Tonga-Hunga Ha’apai volcano a month earlier, the largest volcanic eruption anywhere on Earth so far this century, and how these volcanoes can supercharge the atmosphere to make Eastern Australia even more susceptible to heavy rainfall – and that the ash plumes could be monitored as they cross the Pacific Ocean just as weather stations monitor air pressure and so provide an SOI index.
There was also no mention on the radio that evening of 3rd March 2022 that the BoM seasonal rainfall forecasts are completely lacking in any skill. That the BoM consistently gets its seasonal rainfall forecasting wrong, and that not only did it not forecast the torrential rains at Lismore on 28th February 2022 but that it has so far refused to record any value for the 24 hours to 28th February 2022 at Lismore into the Australian Data Archive for Meteorology.
The most accurate seasonal weather prediction systems rely on statistical models using advances in machine learning to elucidate patterns in historical data. So, the integrity of Australia’s temperature and rainfall record is paramount. Yet both temperature and rainfall records are being constantly eroded by the BoM. Major rainfall events are not being entered into the database. Important weather stations are being closed and the available temperature data remodelled, stripping away evidence of past cycles of warming and cooling that correspond with periods of drought and floods.
But of even more concern to me is that since 2011 the BoM has stopped numerical averaging of the instantaneous one-second readings from the temperature probes electronic probes in its automatic weather stations used to measure temperature. I have shown that this could result in a probe recording up to 0.4 °C warmer for the same weather. To know the effect of this more generally on Australia’s climate through 2022 the parallel data – the measurements taken from mercury thermometers and electronic temperature probes in the same weather stations – needs to be made public. Since 2015, when I first requested this data, the Bureau has steadfastly refused to release it but my appeal against this will finally be heard on 3rd February 2023 by the Administrative Appeals Tribunal in Brisbane.
POSTSCRIPT
* Monday 9th January: Electronic’s specialist Lance Pidgeon has reprimand me for incorrect use of the terms ‘electronic probe’ and ‘electronic thermometer’. The new temperature measuring devices used by the BoM are platinum-resistance probes or platinum-resistance thermometers, specifically they use a PT100 platinum resistor, which is a simple electrical resistor.
And as Lance has further explained, and I quote:
The 2018 version of the WMO standard has been written to remove the BoM excuse for not averaging. Someone there is on the ball. Although I do need to check what the status of this is right now, the wiggle room they found in the 2014 WMO standard had been removed from the 2018 standard last time I checked.
The BoM go against the standards in four ways. All of them important. One of the main reasons the WMO gives for the [numerical] averaging is electrical interference. The BoM as you know claim to have put a sleeve on the platinum resistance thermometer to slow its thermal response time down to match the thermal response time of a mercury thermometer, about 30 seconds at 5 M/S wind speed. This does nothing about electrical noise. Nothing at all. It is electrical noise that could randomly synchronize with any one of the the 60 spot readings to shift the temperature up by 0.3 for a single reading and if it happens to increase at a rate of 0.3 per second and continue to syncronise for the right 60 samples then an 18 degree increase is theoretically possible…
More on the other ways BoM go against the WMO standard in a future blog post.
**Report to be published by the Institute of Public Affairs.
Karl Penna says
Many thanks for this informative information, I glad to see some common sense in this debate,I have concluded that I Don’t believe anything from BoM or mainstream media anymore and I feel it is a sad indictment that the narrative has no focussed on what so called climate scientists of main stream say . As I have written before on weekend Australian September 17-18 2022 on the front page was an article quoting a number of international scientists in a study that” no climate emergency” evidence in the record to date. But did this reach the likes of ABC or other media outlets, I think not. Such a pity as you say that our children are being manipulated to fear rain. Thank you so much for your thoughtful and invoking article
hunterson7 says
Flannery’s climate flim flam has cost Australia hundreds of billions in bad policies, unnecessary expenses, irrational fear, and corruoted science.
Enough.
Glen M says
The new highway mentioned does not affect Lismore as it traverses the lower , downstream sections of the Richmond River around the towns of Broadwater and Woodburn. When the river opened its banks the floodwaters piled up against the new Pacific Highway. The country to the east is Melaleuca and Teatree and takes regular inundation,; this occurred but as the floodwaters were not able to flow through in many parts the dispersal was arrested somewhat. Once again, this flood event was due to the extremely high rainfall in the Wilson catchment falling on already saturated ground. Macadamia plantations do not help.
Glen M says
Further, this event cannot be attributed to climate change – as all other weather phenomena cannot. Manipulation for political ends which feeds the ignorant majority and keeps them in fear. Thankyou Jennifer.
Hasbeen says
Our records in my district, south of Brisbane, go back far enough to give our wettest year on record as 1893 with 1726.5mm. The next wettest was 1954 with 1475.7mm, 61 years later
Then 68 years later 2022 was very wet & has now taken second prize at 1715mm.
It is a bit hard to see any trend here, or any reason to blame poor innocent CO2 for controlling the weather.
Greg says
Your observations are always so welcome. I remember standiñg next to the wall ofthe then the main water supply for Armidàle nsw, the Dumaresq Dam, that was empty. My parents relied on rainwater tànks for ŵàter. Shortly after, the 1974 floods ensured that the Moomba gas plant in central Australia was sandbagged to keep oùt the water!
Fyi Richmond was flooded three years after being settled and continues to be so every few years. It is a floodplain!
Greg
Siliggy says
Hi Jennifer
After seeing a house my mother had built washed out on to the road in the news from Eugowra, I dug through the Trove newspaper records and other sources to investigate the history of floods there. This to settle a dispute with a family member about how often the place flooded. Was surprised to find things like “Boneys great ride” and “The actual height of the flood can not be judged, as the gauge, and the bridge to which it was attached, was completely under water.” from previous floods.
Thanks to Warwick Hughes of “Errors in IPCC climate science” for letting me put this list of finds here at this link.
http://www.warwickhughes.com/agri16/6Eugowra.html
A very interesting reply i got for this recently was:
“Mantaray Yunupingu
January 8, 2023 at 8:44 am · Reply
Siliggy. We are currently going through this BS once again with the WA floods up north, as Fitzroy Crossing gets inundated (up to a point).
Here’s the ABC:
http://www.abc.net.au/news/2023-01-07/kimberley-flood-crisis-continues-fitzroy-crossing-isolated/101834840
….”The Fitzroy River peaked at a record height of 15.8 metres at Fitzroy Crossing on Wednesday afternoon”
Here’s the Tourism Info Website…
https://www.fitzroycrossingtourism.com.au/whats-on-local-information/fire-food-emergency-information/fitzroy-river-floods.aspx
Every flood at 19 metres and more! WTF?”
Siliggy says
The history of the platinum resistance thermometer. It took about 25 years to get a bit of wire to work right.
1861 “The letter goes on to describe the instrument, a rod wound with silk-covered copper wire in several layers, covered with rubber, and connected to a battery and a galvanometer in the cabin. ”
https://technology.matthey.com/article/24/3/104-112/
Don Gaddes says
The BoM has never acknowledged the effect of volcanic activity on temperature and precipitation over Australia,(or anywhere else.)
The continued precipitation effects of North-West cloud-bands originating from especially Indonesian volcanism and culminating in flooding across South-Eastern Australia, shows a distinct lack of knowledge within the BoM regarding the heat-source and albedo effects of volcanism – and the fact that the Earth’s Axial Spin moves volcanism-induced precipitation South-East towards the Pole in the Southern Hemisphere – and North-East towards the Pole in the Northern Hemisphere.
The reason the BoM’s precipitation and temperature averages are so wildly inaccurate, is that they are blatantly, ignorantly and fraudulently fabricated. Volcanism is disregarded.
Without considering all the parameters making up an average – there is no average.
John Hultquist says
“ the 1961–1990 average ”
Standard practice by meteorologists is to move to updated periods for the comparison averages, defined as “Climate Normals”, after the year ending in “0” is finished.
Thus, the current comparison period is 1991-2020. This has been standard practice in the USA and other countries since 1950. There may be occasions when it is not done.
Note the use of “Climate Normals” (sometimes “climatological” is used): Normal is most often used in a somewhat different way. Example: That kid is being a brat, and that is not normal. Another thought: Do people object to the score of “Love” in tennis? No. So don’t object to the use of “Climate Normals”.
Ian George says
‘…… official rainfall gauge in Lismore failed. Yes, failed on 28th February 2022.’
The rain gauge at Lismore failed around 3:00am on 1 Mar 22 and had recorded around 330mls for that day. It was still raining heavily until at least 9:00am. I wish I had taken a screen shot.
Sam says
“Professor – even the rain that falls isn’t actually going to fill our dams – Tim Flannery is Chief Councillor. First among equal climate catastropharians, as it were.
To the letter, signed by Flannery and another 81 (on my count) others. It reminds me of Einstein’s retort about the book, One Hundred Authors Against Einstein, published in 1931. When asked to comment, Einstein reportedly replied to the effect that to defeat the theory of relativity one did not need the word of 100 scientists, just one fact. One fact, you’ll notice. Not a factoid. Not a tendentious proposition masquerading as a fact.”
“IPA publication, by Dr John Abbot and Dr Jennifer Marohasy, injects a much needed balanced scientific and historical perspective into the ocean of hyperbole.”
https://quadrant.org.au/opinion/doomed-planet/2023/01/their-truth-is-the-agenda-facts-go-hang/
Frank Vardanega says
Great article as usual except for one key point. In the interests of clarity and completeness when the Wivenhoe Dam is “full” that relates to water storage for drinking and other processes. At that point it is actually only 50% full. The flood mitigation capacity of Wivenhoe is the other 50% of its maximum capacity.
Sam says
While blinded by their climate paranoia, The Greens, the Teals, etal cheer on fireworks.
“The Sydney New Year’s Eve Party is one of the largest and most advanced fireworks display anywhere on earth, spend a budget of $7 million on eight tonnes of fireworks.”
Perhaps fireworks will be their next target, considering:
“By understanding the carbon footprint of fireworks (how much CO2 fireworks produce), you can use this guide to make environmental conservation efforts by using offsets to erase the harmful impact.”
https://8billiontrees.com/carbon-offsets-credits/carbon-footprint-of-fireworks/
jennifer says
Thanks Lance, and I’ve added the following as a postscript since receiving your email, and repeating the same here:
Electronic’s specialist Lance Pidgeon has reprimand me for incorrect use of the terms ‘electronic probe’ and ‘electronic thermometer’.
The new temperature measuring devices used by the BoM are platinum-resistance probes or platinum-resistance thermometers, specifically they use a PT100 platinum resistor, which is a simple electrical resistor.
And as Lance has further explained, and I quote:
The 2018 version of the WMO standard has been written to remove the BoM excuse for not averaging. Someone there is on the ball. Although I do need to check what the status of this is right now, the wiggle room they found in the 2014 WMO standard had been removed from the 2018 standard last time I checked.
The BoM go against the standards in four ways. All of them important. One of the main reasons the WMO gives for the [numerical] averaging is electrical interference. The BoM as you know claim to have put a sleeve on the platinum resistance thermometer to slow its thermal response time down to match the thermal response time of a mercury thermometer, about 30 seconds at 5 M/S wind speed. This does nothing about electrical noise. Nothing at all. It is electrical noise that could randomly synchronize with any one of the the 60 spot readings to shift the temperature up by 0.3 for a single reading and if it happens to increase at a rate of 0.3 per second and continue to syncronise for the right 60 samples then an 18 degree increase is theoretically possible…
More on the other ways BoM go against the WMO standard in a future blog post.
Sam says
Wikipedia once had an article :
“List of scientists who disagree with the scientific consensus on global warming”
Jennifer Marohasy, is on the list.
Wikipedia subsequently deleted the entire article, “in accordance with Wikipedia’s deletion policy”.
However, the deleted article is available from the Web Archive :
https://web.archive.org/web/20191115154603/https://en.wikipedia.org/wiki/List_of_scientists_who_disagree_with_the_scientific_consensus_on_global_warming
FYC
Sam says
Hello Clover Moore.
The recent 7 tonnes of Sydney, New Year fireworks – unleashed I am told – 3.5 tonnes of CO2.
And you tell me to ride a bicycle.
ianl says
A good piece, Jennifer.
Your irritation with the BoM’s slipperiness and crab-walking is deserved and comes through with clarity.
I can only hope the AAT upholds your appeal on the non-release of comparative temperature data. Myself and colleagues nearly a decade ago were speculating that simple weather records (temperatures and rainfalls, as you say) would become classified data.
The BoM’s refusal to acknowledge geological events as influencing weather is particularly irritating. Book burning at its’ most prejudiced. In discussion on occasion with some of the CSIRO activists, I’ve been told that such data is “irrelevant” – just why is never answered.
richardsb61 says
The BOM is showing that it is not fit for purpose because they rely on fiddling data to make natural events appear to fit the thoroughly discredited climate narrative which is failing across the globe. Even the intensely cold conditions being experienced in N America are blamed on global warming caused man whilst the ordinary citizens look on and say that the climate narrative belongs to another planet.
John Hultquist says
@ Sam says – – – Way Back Machine
Thanks Sam.
That’s an odd list. First a person has to be well known enough to have a web page. That restricted the list a lot.
I suspect it was removed because keeping up with the growing number of skeptics became problematic. Was the growth slowing, going linearly up, or exponentially up?
Inquiring minds would like to know.
Congratulations to Jennifer for making the list.🧑🎄
Siliggy says
Here are links to the latest WMO 8 standard Volumes I, III and V .
I https://library.wmo.int/doc_num.php?explnum_id=11386
III https://library.wmo.int/doc_num.php?explnum_id=11384
V https://library.wmo.int/doc_num.php?explnum_id=9869
From Volume I 1.6.11
“. A sample is a single measurement, typically one of a series of spot or instantaneous
readings of a sensing system, from which an average or smoothed value is derived to make an observation.”
Note an “observation” is not a single sample but an averaged or smoothed series of them.
From Volume I ANNEX 1.A. right at the top of the table “Output averaging time” = 1 Min.
Note this is output averaging not input averaging.
From the explanations just below the bottom of that table:
“: to exclude the natural small-scale variability and the noise, an average value over a period of 1 min is considered as a minimum and most suitable; averages over periods of up to 10 min are acceptable.”
From Volume III 2.7
“Thermometers with a time constant of 20 s should preferably be used to avoid excessively small fluctuations in temperature (average wind speed of 5 m s–1), or, in cases of automatic measurements, an appropriate digital averaging or resistance/capacitance filtering should be applied. From memory the older WMO 315 specified 30 seconds for manual.
Note that neither ” digital averaging” or “resistance/capacitance filtering” is thermal averaging in the Stevenson screen.
From Volume V 2.4.2 (a) ii and figure 2.8
The place a “resistance capacitance” low pass (Time constant) filter should go.
“Do not exceed the time constant of an analogue low-pass filter following the
linearized output of a fast-response sensor;”
“Thermometers with a time constant of 20 s should preferably be used to avoid xcessively small fluctuations in temperature (average wind speed of 5 m s–1), or, in cases of automatic measurements, an appropriate digital averaging or esistance/capacitance filtering
should be applied.
20 seconds at 5 meters per second wind speed for the time constant of manual thermometers is a change down from the old WMO 315 specification of 30 seconds.
Siliggy says
Perhaps the most important words in the latest WMO 8 standards are from Volume V 2.4.1. “However, the sensor and the sampling must be matched to avoid aliasing. If the sampling rate is limited for technical reasons, the sensor/filter system must be designed to remove the frequencies that cannot be represented.
The BoM only use one sample per day for maximum temp and one for minimum temp. This limits the sampling rate to not 1 per second but one per day that is not averaged with anything. A sampling rate of 1 per day is not matched to the time constant of the sensor by any stretch of the imagination. It takes at least two samples per time constant to make an average and counter higher frequencies aliasing down from unfiltered electrical interference.
Volume V 3.2. Has a slightly more plain English wording.
“An important design consideration is how often the transducer output should be sampled. The definitive answer is: at an equispaced rate at least twice the cut-off frequency of the transducer output signal. However, a simpler and equivalent rule usually suffices: the sampling interval should not exceed the largest of the time constants of all the devices and circuitry preceding the acquisition system. If the sampling rate is less than twice the cut-off frequency, unnecessary errors occur in the variance of the data and in all derived quantities and statistics.”
Keeping just one sample per day makes the sampling rate one day long. The BoM would have us believe that the sampling rate is once per second and therefore fast enough to meet the standard to remove unwanted higher frequency aliasing. But deleting the unused samples within the time constant means they are not used to remove any high frequency that may have affected the highest or lowest single sample that is kept.
Lance Pidgeon
Phillip says
I keep a close eye on the reported daily temperature maximums from our local AWS because I’m interested in how close the predicted max gets to the actual max. It’s very rare that the half hour temperature records ever show what is the reported daily maximum.
When I look at the half hour readings at the end of the day, I look to see what the highest temp recorded is. Typically it’s at least 0.5 C lower than the actual maximum reported for the day. I’ve seen the difference between the high on the table to the maximum reported as much as 2 C above the maximum recorded on the half hour temp data table. I look at the data and can never see where this maximum is coming from. Is this the spurious spike that’s not average out that is being reported as our maximum?
On the 20/1, highest temp reported on the table, 27.3, BOM reported a maximum 27.8, (0.5 higher) 19/1 22.4 on the table, reported max 23.2. (0.8 higher).
For an example you can look at the 30 min temp data, and from 2pm to 6 pm the high temps are relatively constant, 21.4, 21.9, 22.4, 22.9, 22.4, 22.2, 21.9, 22.4, 21.6, then they report the Max at 23.2, with nothing close to that temp in the table except the 22.9. Why the difference and why always higher? Is it just that they don’t table the maximum high temp at the time it’s recorded and just reported later?
Graeme Lehmann says
My internet research uncovered the Wilson River( Lismore floods) & Hawksbury/ Nepean River( Sydney floods) river heights for the last 100 years. The flood levels & frequency have not worsened.
Ian George says
Phillip,
I also check the temps from my AWS. Weatherzone shows 10 min intervals for the day and I check those against the BoM high temp and find the same discrepancy as you (the BoM gives 10 min data but it disappears quickly). Sometimes the high temp coincides with a 10 min interval and I have seen up to 0.8C in the same minute.