Bourke: How 1km of land clearing can warm a million square miles

Yet again, we have to ask: does the Bureau of Meteorology care about Australia’s long term climate trend? Are they even trying?

Bourke could be one of the top ten most influential temperature sites in the world, mostly by virtue of being miles from anywhere, and used to homogenize a large slab of the land mass of Australia. Bill Johnston documents how changes to the site create most of the temperature trend.

The Bureau of Meteorology’s fancy magical and secret homogenization protocol does not detect changes that obviously affect the temperature (like the clearing in the photo below). But sometimes the BoM make “corrections” because of site changes that don’t appear to have mattered. Is it conveniently selective or just inept?

The BoM don’t even document major site changes a lot of the time. Even iconic sites that affect huge areas are badly managed. Someone got the tractor and plough and cleared the vegetation. As usual, a citizen scientist, a volunteer, documents it (along with a suite of other site changes).

Bourke, Bureau of Meteorology, site changes, photograph, land clearing.

In the last ten years land was cleared around the thermometer. This denuded area has a lower humidity, and higher volatility of temperatures.  The data from this thermometer may be used to “correct” thermometers 1,400 km away.

Bourke Australia, Satellite view. "Back of Bourke".

Bourke Australia, Satellite view. “Back of Bourke”.

The town is the last outpost of civilization, so infamous it has it’s own cliche: “The back of Bourke”.  If there was a perfect thermometer in Australia, this place would vie for the top spot with records going back to 1871, on the crossroads to nowhere and one of the last almost untouched towns –historic, but not urbanized enmasse. And it is an official ACORN site, considered one of the best quality records in Australia. Bourke is at the crossroads to Australia’s outback  and is one of the last almost untouched towns –historic, but not urbanized enmasse.

But thanks to Bill Johnston, we now know that even out here the long hand of incompetence and bias has romped through the data. Again, Bill documents a site that has been watered,  moved, gone electronic, had a new screen, shifted to the airport, and then just in the last few peak years — as climate change became “life or death” — someone cleared the ground all around it and no one at the BOM noticed.

In a Bermuda-triangly type mystery, the station went “electric” but instead of getting better data, for a few years the temperature was only recorded in whole rounded integers. (So much for the tenth of a degree of accuracy, eh?) Plus two or three weeks of data went missing each year, and the site failed performance checks twice.

The wonderbar Technical Advisory Forum set up to boost confidence in the expertise of the BoM didn’t investigate this in 2015. Being consistently irrelevant, they also didn’t investigate in 2016 or 2017 either. What looks like a whitewash, smells like a whitewash…

Likewise, two-rounds of expert peer-review fail to address such obvious problems in the Bureau’s homogenisation methods?

Bourke is so hot it was the place they sent trains to in 1896 to rescue people from a monster heatwave.  Bourke is used to homogenise stations like Alice Springs which is 1,400km (860 miles) away. Does this little clearing “heat” a million square kilometers of records? It’s possible.

As usual, Johnston’s short post here is backed up by a longer PDF file which outlines his detailed years of research.

One Nation’s Senator Brian Burston is presenting this information and the paper to the Senate Estimates on Monday morning. Questions need to be answered.

— Jo

 

_________________________________________

Welcome to the back of Bourke where they make the weather warmer

A science post by Dr. Bill Johnston[1].

Main points

  • The climate at Bourke and surrounding sites hasn’t changed. There is no temperature trend, no increased frequency of extremes and no trend in extremes.
  • As no sites have stayed the same, Australia’s long-term weather records are not useful for tracking trends in the climate.
  • Arbitrary homogenisation adjustments coerce data to agree with models. Comparative homogenisation is biased and should be abandoned.

Introduction

Bourke in northwestern New South Wales is synonymous with ‘the bush’; Clancy of the overflow; crows flying backwards to keep dust out of their eyes and mozzies big as chooks…. While caravans and mobile-vans roll-in during winter when its cool and dry they stay away in droves in summer. Rainfall is a low 336 mm/yr; the driest was 86 mm in 2002 and the wettest, 854 mm in 1950. Runs-of-months with zero rain are common and the drier it is the hotter it gets. Irrigation along the Darling River and dryland grazing of cattle, sheep and goats (and tourism) supports the town’s 2,000 people.

The history of the place

Starting in 1871 Bourke ranks with Sydney Observatory (from 1859), Melbourne (1856), Perth Observatory (1897), Hobart (1882) and some lighthouses (Cape Otway (1865), Yamba Pilot Station (1877) and Nobbys Head (1867)) as one of the longest continuous weather records in Australia and one of the longer datasets in the Southern Hemisphere. It is also one of 104 non-urban ACORN-SAT sites (Australian Climate Observations Reference Network – Surface Air Temperature) used to calculate Australia’s warming.

Site and instrument changes effect measurements. The environment surrounding the site has not remained consistent; the Stevenson screen has not stayed in the same place and equipment used to measure temperature has changed also.

Observations were first reported from the telegraph office and after it burnt down on 8 November 1874 the office moved to another building, which it shared with the post office. A new post office (with residence) was built in 1880 in Oxley Street several allotments east of the courthouse, which is on the Richards Street corner (Figure 1). The second storey was added in 1889 and modifications continued until telegraph and postal services merged to form the Post Master Generals Department in 1901.

The large 230-litre Stevenson screen installed in 1908 moved at least once in the post office yard and from the 1950s it was shaded and surrounded by watered lawns. It was replaced (and probably moved) in 1964 and due to continuing “vegetation problems” observations ceased there in August 1996.

Thermometers were observed in another 230-litre screen beside a dusty track at the second airport north of town in 1994. That site was superseded by an automatic weather station (AWS) 700 m away in 1999, which used a small 60-litre screen and which reported whole-degrees before 2002. The many temperature values that were culled shows the AWS was frequently over-range, probably because its rapid-sampling probe operating in the small screen recorded flurries of warm air that would not affect thermometers housed in large screens; or that due to calibration problems it was prone to spiking on warm days.

The AWS site was ploughed-around in 2013, which made it even hotter

Bourke, Aerial view, 1941, Photo.

Figure 1. The approach to the then RAAF landing ground in 1941 looking north over Bourke to the Darling River. The courthouse (C), Lands Department (L) and post office (P) facing Oxley Street are visible with trees (T) established around the post office (From the National Library of Australia aerial photograph collection).

Understanding data requires careful analyses and research. Step-changes detected using independent statistical tests are aligned with reports in newspapers and archives (National Archives and National Library of Australia); museums like the Airways Museum at Essendon and the RAAF Museum at Point Cook; and checked using historic aerial photographs and Google Earth Pro (Figure 2).

Bourke temperatures are hotter now than in the past because of site changes, not the climate.

Because sites change, data collected to describe the weather are often not useful for benchmarking trends in the climate. Shade, watering and the new building caused changes at the post office and the hotter it was the more watering was probably done to cool the place down. Daytime temperature is warmer at the airport especially in summer and Google Earth Pro satellite images show the current AWS site was ploughed around before 2013, which according to Blair Trewin[2] is “Australia’s hottest ever year”. The most recent ‘record’ temperature at Bourke (48.3oC on 12 January 2013) is due to ploughing not the weather.

Bourke Streets, photo.

Figure 2. Close-up views of high-level (25,000 feet (7,600 m)) aerial photographs shows the post office (P) with trees in the yard, the Lands Department office (L) and courthouse (C) on the Oxley-Richard Street corner in 1952. By 1963 a new building (?) (which Google Street View shows is now a bank) occupies the vacant lot which before 1877 was to have been the town goal.

 

Its hot when it’s dry and cool when its not and careful analysis outlined in the attached Bulletin shows the climate of Bourke hasn’t changed. Temperature trends and frequency of upper-range extremes has not increased. The AWS-site is neglected; out-of-range values are selectively culled because electronic thermometers housed in dusty 60-litre Stevenson screens spike randomly on warm days.

Recent temperature records at Bourke are due to ploughing; those at Wanaaring are due to the small screen moving from behind the post office, where the lawn was watered, to beside the dusty track to the tip in 2003. Brewarrina’s data are warmed after 2002 by new hospital accommodation; while at Cobar data are affected by urban encroachment. Like ploughing, establishing AWS at the hottest sites imaginable (Figure 3) is just another trick. While the Bureau warms the data the climate hasn’t warmed or changed.

Bourke area, NSW, Weather Stations, Bureau of Meteorology.

Figure 3. Eight of 11 new AWS established in NSW in 2017 are in the arid northwest corner where its bound to be hot. (Pre-existing sites are in upper-case.) (Map courtesy of Google Earth Pro.)

 

Homogenisation

ACORN-SAT is the sum of its parts and Bourke is just another example of where arbitrary changes create trends that don’t reflect local weather. Recent claims of record warming are not supported by individual site data. (Bourke homogenisation is outlined in Part B of the Bulletin.)

Across the network site-changes are not rigorously documented, some are ignored and some that make no difference are adjusted as though they did. Furthermore, selecting faulty (correlated) data to adjust ACORN-SAT datasets results in bias. The default position that unexplained data-changes are attributed to the climate allows climate-changes to be specified in advance and data to be homogenised accordingly.

Australia’s ACORN-SAT temperature datasets are riddled with problems. The process is opaque; lacks statistical control; synchronous inter-site changes such as replacing 230-litre screens with 60-litre ones and thermometers by AWS at infrequently serviced sites beside dusty tracks and in paddocks at airports, are propagated across the network by the process. Thus few ACORN-SAT datasets are independent of collective problems. Using comparator data that are not homogeneous to adjust faults in ACORN-SAT has no merit and should be abandoned.

Conclusions

  • The Bureau’s ardent support of climate warming has overtaken its job of monitoring the weather. Replacing observers with AWS and 60-litre Stevenson screens beside dusty tracks, which are checked at most places less than once per year has warmed Australia’s climate.
  • It’s always been hot at Bourke especially when it’s dry. The climate hasn’t changed; temperatures have not increased nor are extremes more frequent or increasingly severe.
  • It is remarkable that homogenisation has gone-on for as long as it has. Changing data to agree with models is unscientific. For all its complexity the process is faulty and should be discontinued.

[1] Bill is a former NSW Department of Natural Resources scientist with extensive experience in weather monitoring and climate data analysis.

[2] https://theconversation.com/2013-was-australias-hottest-year-warm-for-much-of-the-world-21670

9.4 out of 10 based on 84 ratings

59 comments to Bourke: How 1km of land clearing can warm a million square miles

  • #
    Sceptical Sam

    I hope that One Nation’s Senator Brian Burston understand’s that those attending the Senate Estimate’s Committee meeting will not have an answer to his question.

    They will “take it on notice” and come back (maybe) in due course with an answer that bears no relationship to the questions.

    They’ll play him for a fool which, as it happens, he isn’t.

    300

  • #
    el gordo

    “Parts of Sydney are going to be hotter than Bourke [in the state’s far north-west],” Kim Westcott, a meteorologist with Weatherzone, said. “You don’t tend to see it that often.” SMH

    We’ll never know, the system is corrupted.

    223

  • #
    bill johnston

    There is no trend, no increase in the frequency of extremes or trend in extremes at Bourke or Sydney Observatory data,

    Cheers,

    Bill

    293

  • #
    Environment Skeptic

    Great piece. Thanks Jo

    120

  • #
    Extreme Hiatus

    Excellent detective work. Still more bad news about the quality of data from the ACORN system, for starters.

    Time to give the global version a more appropriate name: United Nations International Climate Observations Reference Network System. UNICORNS.

    I don’t believe in unicorns or the products of UNICORNS.

    300

  • #
    PeterS

    OK OK – perhaps I shouldn’t have used the fr— word.

    This sort of thing has been happening for decades. The shenanigans carried out by so called climate scientists are despicable and tantamount to fr….

    191

  • #

    All statistics are trash, some are useful trash, some are interesting trash…and some are utter trash. The trick is not to turn the useful and interesting trash to utter trash by homogenising, smoothing, substituting, proxifying, inferring and otherwise guessing.

    (By the way, temp records are trash because they tend to be based on what clouds happened to be passing or not passing at the potential hottest or coolest part of the day. Is a day hot if it is 40C at two in the arvo after being 20C at nine in the morning? Or is it hot because it was 30C at nine in the morning before a cool change? What do statistics tell us without the application of commonsense and observation? They tell us everything and nothing.)

    313

  • #
    Mikky

    I have reconstructed monthly average maximum temperature variations in the Bourke region back to 1871. It was relatively warm in the late 19th century, especially for short periods, similar to temperatures today. It was relatively cool in the early to middle 20th century:

    https://diymetanalysis.wordpress.com/2017/11/09/example-02-walgett-tmax/

    120

    • #
      Curious George

      In many (at least, some) temperature series latest readings are used to adjust past temperatures. Do we know how this 2013 land clearing influences the official (adjusted) 1871 temperatures?

      11

  • #
    EternalOptimist

    And now for tomorrows homogenised weather. A ridge of high pressure 1400km to the west means it will be hot and clear for most of the day with low winds, this will gradually ease the low to the north, three countries away, where there will continue to be tropical downpours. Cool and in new Zealand with winds gusting to 50 kph and cold. Continued freezing of the ross ice shelf will also affect local conditions. So if you must go out tomorrow, remember the sunblock, raincoat, thermos flask, thongs and cozzie.

    122

  • #
    toorightmate

    OFF TOPIC
    Nest Monday, THEIR ABC 4 Corners program will be all about how the climate is changing rapidly in Australia.
    They will not be talking to politicians, but will be talking to scientists and farmers who “really know” how Australian climate is changing.
    I am certain the ABC will trot out the usual Green fanatics to maintain the ABC’s stance as flag bearers for the Green movement in Australia.
    It would not surprise me if they show some footage of bananas growing at Port Arthur.

    120

    • #
      Robber

      Is 4 Corners supposed to be news or opinions?
      The ABC has copped criticism this month over the execution of the so-called Cabinet Files series, its subsequent apology to former prime minister Kevin Rudd and the publication of taxation stories by chief economics correspondent Emma Alberici. In an email to staff on Tuesday, the ABC’s head of news Gaven Morris announced a restructure of senior positions at the broadcaster and conceded there had been “a number of editorial issues” and indicated a need to improve processes, particularly with regard to the ABC’s online output.

      10

  • #
    Richard Ilfeld

    & with a tip of the hat to the surface stations project reported at WUWT.
    It seems that there are and have been issues with reporting everywhere.
    This isn’t really surprising. Absent hysteria the temperature from day to day for
    forecasting and normal reporting can wiggle a little, and will. When I look at my local map on
    the internet, I see about 30 stations in a 40 mile circle. and I see about 6 degrees of variance.
    No tenths reported.
    And I am happy the airport sensor reports temps and RVR at the runway, not across town.

    My point here is the old question about whether the climate folks are venal, trying to manipulate us,
    or moderately incompetent.

    An honest scientist would have seen the reporting issues, and tried to solve the problem. Perhaps some did.
    An ****** ********* might have seen an opportunity.

    No doubt there have been some honest technicians toiling in the labs over the years. But the head honchos seem to be playing ditry pool to nefarious purpose…..I’ve seen dozens of these stories over the years, and the adjustments always work out the same way.

    I’m over any allowances. What should be getting hotter is the pursuit of these scum by auditors and inspectors. The damage done by the temperature cult is becoming economically equal to the largest financial scams in history, and equally damaging.

    Someone who manipulated a stock market to this degree would receive a long sentence, for damage done.

    ?????

    112

  • #
    pat

    all I know is there’s something fishy about almost every year, no matter what, being declared the hottest year evah blah blah:

    25 Feb: AP: Rare snowfall blankets Rome, closing schools
    By NICOLE WINFIELD; Associated Press writer Nataliya Vasilyeva in Moscow, Jovana Gec, in Belgrade, Serbia, and Kirsten Grieshaber in Berlin, contributed to this report

    Romans woke up to a rare snowfall Monday, after an Arctic storm passing over much of Europe dumped enough snow to force schools to close and public transport to reduce services.

    Italy’s civil protection agency decided to deploy the army to clear streets in the capital after the snowfall paralyzed Rome with just a few centimeters (inches) of snow.

    Parks that usually stay green through winter were blanketed with snow, giving eager Romans a rare opportunity to go sledding. Even the Circo Massimo became a hotspot for snowball fights, while Piazza Navona, with its famed Bernini fountains, turned into a snow-dusted winter wonderland.

    Rome’s Mediterranean climate and proximity to the sea usually result in mild winters, such that restaurants often keep outdoor seating open even through the coldest months of the year. As a result, the Monday morning snowfall, though not huge in quantity, brought excited young Romans out to play in the snow or walk in the slush.

    Mayor Virginia Raggi signed an ordinance Sunday evening closing public schools as a precaution, and many private ones followed suit.

    Elsewhere in much of northern and central Italy, the storm also closed schools and disrupted transport.

    In Moscow, temperatures dropped to this winter’s low despite the approaching spring. The mercury in the Russian capital dropped to nearly -20 C (-4 F) on Sunday night, the coldest this winter, the Meteorological Office said Monday.

    Meteorologists are forecasting unusually low temperatures for early March. Roman Vilfand, chief of the Russian Meteorological Office, told the Interfax news agency that Muscovites should brace themselves for frosty weather in early March and could only “count on the warmth of the soul,” not higher temperatures outside.

    Croatia, meanwhile, has been gripped by freezing weather, with even towns along most of the Adriatic coast waking up to temperatures below freezing. The spell of winter weather has closed schools in the northwest, and heavy vehicles were banned from all roads leading toward the coast.

    About 1,000 Croatian soldiers have joined efforts to clear the snow in the worst-affected areas where more than 1.5 meters (about five feet) of snow have been reported…

    Snow and freezing temperatures have a grasp on some parts of Germany as meteorologists reported a record cold for this winter of -27 C (-16.6 Fahrenheit) on the Zugspitze mountain in the Alps.

    The German Weather Service said Monday that the overnight temperatures were also low in the south and east of the country, where they went down to -15 C (5 F) in parts. It was slightly warmer in the northeast, but traffic there came to a halt in some regions because of heavy snowfall…
    https://apnews.com/738d732649de4894b19a478c434941a1

    40

  • #
    Gary

    Jo, maybe Australian English is different from American English, but I have a question: why do you use a plural verb with a singular collective noun? E.g., “Yet again, we have to ask: do the Bureau of Meteorology care … Granted, the Bureau is composed of people, but it’s a singular entity so the verb should be “does”. I’m seeing this grammatical construction everywhere and wondering why even professional writing has gotten lax. It’s not a big deal, just jarring to these old eyes and mildly ironic that it occurs in a criticism of crumbling temperature monitoring standards.

    131

    • #

      Gary, You’ve convinced me. I’ve changed do to does.

      I confess in school, I could not see much point in grammar, unless it conveyed a different meaning, grammar rules looked like “fashionable dressing” – a way to impress with style rather than content. Being a bit older and wiser, I recognize the downside of distracting people with unconventional/improper use. Happy to learn, but fear I still think of the BoM as a group of plural people. Thanks for your help proofreading 🙂 — Jo

      110

      • #
        William

        Jo, I recommend you read Bill Bryson’s book, “Mother Tongue” – I went from being a prescriptive grammarian to a descriptive one. Most of the rules are the same but you are allowed to break the nonsensical ones. Bryson is a very good and extremely amusing writer.

        40

      • #
        PeterPetrum

        Ah! Now there is the difference between how I was taught in Scotland in the 40’s and 50’s and how you were taught in this wonderful country a few decades later, Jo. We had correct grammatical usage drummed into us (with a heavy ruler or leather “taws” if necessary). No “split infinitives”; no ending a sentence a preposition with (sorry!); correct verb use with collective nouns; correct use of punctuation, such as semi-colons. I know language is a “living thing”, but English, used correctly, can, and should be, exquisite.

        30

      • #
        Sceptical Sam

        Me too, Jo.

        Perhaps Gary might forgive me for my erroneous apostrophe in “understands” at No 1.

        If we had an edit function I would fix it.

        20

      • #

        Gary sez:
        Jo, maybe Australian English is different from American English,
        but I have a question: why do you use a plural verb with a singular collective noun?
        E.g., “Yet again, we have to ask: do the Bureau of Meteorology care …

        Jo Nova sez:
        February 27, 2018 at 11:56 am · Reply
        Gary, You’ve convinced me. I’ve changed do to does.

        My comment:
        After reading two excellent
        Dr. Bill Johnson analyses here,
        I think the appropriate spelling
        for your Bureau of Meteorology is
        “doo-doo” … not “do”, or “does”.

        00

    • #
      PeterS

      Gary, language keeps evolving, for better or for worse. One thing is for sure – it will not stop changing. At least we don’t use Old English anymore. Having said that you are right in terms of the grammar in question – for now.

      10

      • #
        Environment Skeptic

        My short rants worth……
        ‘Russia did this’, and ‘Norway does that’… ‘humanity was responsible’ for something else and the like are a category i call “collective qualification” and are the main reason prejudice and racism etc exist on the planet, in my opinion. More examples of collective qualification are expressions like, ‘scientist’s have discovered’ and instead should always be named and attributions described. This is rarely the case in the tabloid media especially.

        There are all kinds of ways to avoid what i call ‘collective qualification’.

        For example, it is far more accurate to say, “there are those at the BOM who……and continue to…..”

        60

      • #

        ‘Homogenization,’ a chameleon word,
        like so many post-modern terms…
        there’s ‘involved in,’ and ‘linked to,’
        ‘significant likelihood of’ …

        10

    • #
      manalive

      Forms of English handle verb agreement with collective count nouns differently; in particular, in British English it is generally accepted that collective nouns can take either singular or plural verb forms depending on the context and the metonymic shift that it implies … (Wiki).

      “Yet again, we have to ask: do the Bureau of Meteorology care …” sounds OK to me, that use is not “lax” but relaxed.

      10

      • #
        Sceptical Sam

        And, it gives the sense of “collective guilt”; which is proven beyond reasonable doubt, on the evidence.

        00

  • #
    robert rosicka

    Not sure what happened here but glad this post is back .

    [Not sure either. Some kind of new glitch, but at least it is fixed, if not understood. – Jo]

    40

  • #
    OriginalSteve

    Hmm…Bourke is near white cliffs, and white cliffs had/has a large solar steam power set up coz its so stinking hot there….

    30

  • #

    Oi!

    I made a reply to PeterS. It’s gone! I’m devastated! Devastated, I say.

    Probably not worth reading anyway… 🙁

    20

  • #
    John in Oz

    Why are we surprised at anything the BoM produce?

    From the Climategate HARRY READ_ME file:

    getting seriously fed up with the state of the Australian data. so many new
    stations have been introduced, so many false references.. so many changes that aren’t documented.
    Every time a cloud forms I’m presented with a bewildering selection of similar-sounding
    sites, some with references, some with WMO codes, and some with both

    20

  • #
    el gordo

    Mid 19th century temperature data, looks pretty average.

    http://www.waclimate.net/extreme-temperatures.html

    10

  • #
    Graeme#4

    Perth shouldn’t be regarded as one of the sites with “…longest continuous record”, because the actual measurement site has been moved twice, not counting the original move from the first measurement site in Supreme Court Gardens. In both cases there was a noticeable step change upwards, when compared to Perth Airport measurements, which started in 1942. Today the cool summer record was again quoted as “The coolest in 19 years”, meaning when measured from the current Mt Lawley site. (However, when compared to the Perth Airport site, summer overnight temps haven’t been this cold since 1944, so in fact the coolest summer record would go back further.)

    40

  • #
    David Maddison

    Can someone explain why 230 litre screens were replaced with 60 litre ones?

    Surely the bigger the internal volume the more honest the reading will be?

    31

  • #
    AndyG55

    I found some Bourke data on BOM

    Some little snippets and some simple analysis.

    First BOM notes.

    https://s19.postimg.org/y5oga9r7n/Bourke_combo.png

    Bourke AWS data of the BOM site

    https://s19.postimg.org/sq4k7xysz/Bourke_AWS.png

    And the one that is really laughable, Bourke missing data.

    https://s19.postimg.org/6tr7zcar7/bourke_missing.png

    21

  • #
    Bitter&twisted

    “Changing data to agree with models is not scientific”

    No it is [snip for legal reasons].

    00

    • #
      Bitter&Twisted

      “Changing data to agree with models is not scientific”
      It certainly is not and in other areas of science, commerce, or industry would be considered to being “economical with the truth”.

      Hopefully this comment is considered reasonable?
      I still believe my snipped comment was an accurate reflection of what is happening.

      00

  • #

    “… for a few years the temperature was only recorded in whole rounded integers. (So much for the tenth of a degree of accuracy, eh?)”

    Worth noting that prior to 1972 metrication, 88.51% of all Bourke minimum temperatures were recorded as rounded integer .0 Fahrenheit. Since 1972 the proportion to 2016 was 30.83%. The site began recording correct integers since 2003 and the 2003-2016 proportion of .0C minimum recordings was 9.87%.

    Prior to 1972 metrication, 85.82% of all Bourke maximum temperatures were recorded as rounded Fahrenheit. Since 1972 the proportion to 2016 was 27.04%. The 2003-2016 proportion of .0C maximum recordings was 10.32%.

    From 1916 to 1936, 98.52% of all max and min recordings were rounded .0F. The mean temperature during those years was 20.24C.

    From 1937 to 1943 the Bourke site observer paid a bit more attention with the proportion of .0F rounding at 54.72% and the mean temperature at 20.48C.

    Full-on rounding returned during 1944-1969, averaging 96.35%, while the mean temperature was 19.92C.

    From 1973 to 2016, the proportion of rounded .0C was 28.9% and the mean temperature was 20.47C.

    The 2003-2016 proportion of .0C maximum recordings was 10.10% and Bourke’s mean temperature was 20.89C.

    I note that the few years cited by Jo and Bill of 1999 to 2002 had a rounded .0C average of 92.05% and a mean temperature of 20.32C. Bourke’s following four years, 2003-2006, had a rounded .0C average of 11.43% and a mean temperature of 21.14C – up 0.82C on the previous four years of AWS recordings. I would expect an AWS to round evenly so the sharp temp increase may simply have been hot weather.

    Rounding proportion up, temperature down. Rounding proportion down, temperature up. The likely explanation is the pre-metric observers truncating the temps rather than rounding evenly up and down, a common behaviour. More than 50% of all temperatures recorded at all Australian weather stations were rounded .0F before 1972.

    20

  • #
    • #
      Freedom of Beach

      Thanks Tom. BOM staff haven’t had a pay increase for a few years it seems.
      Perhaps their salaries are indexed to average temperature changes?

      30

  • #
    Hivemind

    You’ve mixed up your units:

    1 km of land clearing, (metric, linear units)

    vs a million square miles (imperial, area)

    10

    • #

      True, but deliberate. The distance from Alice Springs to Bourke is 1,400km and that’s only the distance west to homogenize, not east as well. Since I have not tried to calculate the exact number I wanted a casual, but loosely accurate term. 1.5m km2 (or any other decimal) implies an accuracy that isn’t appropriate without doing some maps and sums.

      21

  • #

    Back before there was no change there was even more lack of change. Looks like a non recording thermometer at 2PM.

    TEMPERATURE.—The temperature of this place is
    worth a passing notice. The thermometer ranges very
    high. It is very variable. It is not uncommon to have
    a variation twenty degrees in a few hours ; yet, notwith-
    standing, it is very healthy ; owing, I suppose, to the
    dryness of the atmosphere. The only complaint that the
    residents are subject to, is the blight. What they call
    sandy blight, is very painful ; the other, the fly blight.
    The eye closes up very rapidly, and may continue for a
    few days ; but very little pain accompanies the swelling.
    I give you the state of the thermometer below from July
    to February, which may be interesting to some of your
    readers.
    THERMOMETER AT BOURKE, AT 2 P.M.
    MONTH. HIGHEST. LOWEST. AVERAGE.
    July 70 .. 48… 60
    August 85 .. 51 .. 65
    September 96 .. 60 .. 73
    October 97 .. 69 .. 75
    November 104 .. 86 .. 96
    December 112 .. 92 .. 103
    1863.
    January 110 .. 92 .. 94
    February 103 .. 76 .. 88

    https://trove.nla.gov.au/newspaper/article/63129767

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    Asleep@thewheel

    I’ve often wondered what putting a dirty great big block of units (with large reflective tinted glass windows on the north-facing side right next to an acorn-sat site), would do to Temperature measurements.

    See Hobart, Ellerslie Road. Not exactly meeting the BOMs weather station siting guidelines… (then again neither did the now closed LaTrobe St Melbourne station)

    I feel some good ol’ fashioned adjustments will fix things up!

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    Ian George

    Jo
    As you are aware, the BoM don’t need to rely on site changes to adjust temps.
    The case in point is Bourke in Jan, 1939. If you compare the CDO (i.e. raw data) and the ACORN data for that month, the BoM adjusted all temps over 30C down (up to a degree) and the two below 30C up by 0.1C. This reduced Jan, 39’s overall average by about 0.4C.
    This also reduced a heatwave of 17 days of +40C temps to 11 days.
    I would really like to see Brian B ask the justification for those changes.
    CDO
    http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_display_type=dailyDataFile&p_nccObsCode=122&p_stn_num=048013&p_c=-461049087&p_startYear=1939
    ACORN
    http://www.bom.gov.au/climate/change/acorn/sat/data/acorn.sat.maxT.048245.daily.txt

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    Here is exact text from Hansard 20268 26Feb18
    https://www.aph.gov.au/Parliamentary_Business/Hansard/Estimates_Transcript_Schedule
    top page 18
    Senator BURSTON: My questions are on temperature data from BOM’s Bourke weather station that raise
    serious scientific concerns. Firstly, Dr Johnson, what are your qualifications?
    Dr Johnson: I have qualifications in science, agricultural science, economics and public policy.
    Senator BURSTON: Can you confirm that you were CSIRO’s top executive for the environment?
    Dr Johnson: My employment history is on the public record. I’m happy to confirm that what’s on the public
    record is accurate. I believe that question has been asked in this committee before, so I will answer it again.
    Senator BURSTON: I wasn’t here. I will move on to the bureau’s temperature data for its weather station in
    Bourke, New South Wales. I seek to table a report from Dr Bill Johnston. He’s a natural resource scientist with
    expertise in soil science and climatology. His wide and extensive experience includes being a weather station
    observer—
    CHAIR: Senator Burston, sorry to interrupt your flow there; we’ll consider this document before—
    Senator BURSTON: I beg your pardon. Sorry, Chair.
    CHAIR: Do you have other questions related to other areas that you can go on to, or are they all around this
    report?
    Senator BURSTON: They’re all pretty well related to that.
    Senator MOORE: I have a question to put on notice

    I was surprised at the extent Estimates was just a procession of GreenLeft Dorothy Dixers and free kicks.

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    Congratulations to Dr. Johnson
    for another excellent analysis.
    .
    .
    It’s nice to know someone
    is still practicing REAL climate
    science out there — digging into the
    potential accuracy of temperature data —
    rather than just jumping to conclusions
    — joining the leftist crowd of nitwits —
    to believe CO2 is evil
    and will cause runaway
    global warming.
    warming.
    .
    .
    If the surface temperature data are
    so compromised from REAL weather
    stations, can you imagine the
    extremely low quality of infilled
    numbers — the wild guesses
    that can never be verified or falsified !
    .
    .
    Wild guesses are used for
    a majority of surface grids
    — even over 40% of the US
    is wild guessed.
    .
    I imagine Australia is similar.
    .
    Surface data are still used despite
    40 years of weather satellite data,
    with very little infilling required,
    but ignored by government bureaucrats
    SIMPLY BECAUSE the huge amount
    of infilling for surface data allows bureaucrats
    to create their own number — they can report
    ANYTHING they want to report
    as the “average global temperature”.

    And of course the economic growth
    around the existing thermometers
    causes “man made warming”
    so why not blame man made CO2 —
    — Dr. Johnson will know the difference,
    but ignorant leftists have blind trust
    in everything their central government
    tells them.
    .
    If they wanted to,
    the government bureaucrats
    could make each year
    +0.1 degrees C. warmer
    than the prior year,
    until they get to
    their magical (meaningless)
    +2.0 degree C. “tipping point”.
    .
    My climate blog
    for people with common sense:
    http://www.elOnionBloggle.Blogspot.com

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    Joanne, thanks as always for keeping ’em honest … or at lease for relentlessly pushing them kicking and screaming in the direction of honesty.

    Keep up the good work,

    w.

    [Thanks Willis. Tenth anniversary coming soon. : -) — Jo]

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