What the BOM don’t say: it’s not the hottest year in Australia according to satellites

For forty years NASA satellites have been circling the Earth covering our landmass day and night.  But yet again, the Australian Bureau of Meteorology has released the obligatory “hottest ever year” media release without mentioning that it wasn’t the hottest year in the far more accurate satellite record of Australia, and that this new “record” depends entirely on adjustments and quite possibly on ignoring all the data recorded in the 1800s. Once again they miss the chance to remind Australians that it was almost certainly hotter for hundreds of years seven thousand years ago. Sea levels were higher then too.

They claim it’s the driest ever year, and maybe it was, but they don’t say that there is no trend in droughts and rainfall for the last 178 years.

So to help them out I’ve graphed UAH satellite temperature record which shows that last year was the 4th hottest year since 1979 when the UAH satellite data set begins.

Perhaps in 2020 the Australian Bureau of Meteorology will set their own record, and explain for the first time how and why they adjust their data continuously and post hoc. The Australian surface data is all changed with a mystical secret technique that cools historic thermometers in paddocks, warms them in cities, and can’t be explained to anyone outside the sacred BOM guild (see the marvel of homogenization). They also might explain why they insist on ignoring the superior satellite data and try to measure a vast continent with flawed surface stations placed next to airport tarmacs, car parks, asphalt, incinerators, skyscrapers, super highways, and basically in sites and that are often not compliant with the BOM’s own standards and using super fast electronic sensors in a way that is not WMO compliant either. Let’s not forget they also get data from boxes that are a quarter of the original size, that move all the time, and that many modern records are just meaningless electronic one second “moments” that could never have been recorded in 1910 (or even in 1980). With so many scientific bombs, the marvel is that 2019 wasn’t even “warmer”.

Australian Annual Temperature (UAH)

The hottest year in Australia was 2017, then 1998, then 2016 and then 2019

According to the BOM the year 1998 was +0.96 °C above the 1961-1990 average and last year was nearly 0.6 degrees warmer that that. But according to the NASA Satellites, this year was a tenth of a degree cooler than 1998. The gap between satellite measured 1998 and BOM measured 1998, as compared to their 2019 measurements, is now almost as large the entire warming trend for the last century.

 

 UAH Satellite data

YEAR Australia
ave temp Degrees C
1 2017 0.71
2 1998 0.70
3 2016 0.59
4 2019 0.58
5 2018 0.51

No doubt the honest scientists at the BOM will issue a correction to all their incomplete press releases any day now, unless of course, they are trying to scare more money out of Australian taxpayers, in which case they probably don’t want Australians to know how different the satellite measures are.

DATA: Update Jan 9th 2019  from http://vortex.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt

UPDATE: Vishnu reminds us that Roy Spencer says a 0.6C difference between UAH and the BOM surface temperatures can occur in especially dry years during summer (though he found the opposite effect happens in winter, and we are discussing whole annual averages here). But both 1998 and 2019 were both very dry years, so we’d expect both years to diverge in the same direction which they do not.

Thanks especially to Geoff, with help from Ken, Ian, Ed, Chris, Warwick, Lance and Tony.

To find out the real history of the Australian climate start here:

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9.8 out of 10 based on 84 ratings

135 comments to What the BOM don’t say: it’s not the hottest year in Australia according to satellites

  • #
    Sceptical Sam

    The negligence and outright incompetence, not to mention potential [SNIP], is monumental.

    Trust the BoM?

    Not me.

    Audit now.

    301

  • #
    nb

    ‘and can’t be explained to anyone outside the sacred BOM guild.’
    Divulging the secrets of the soothsayers results in an eternity of torment. Don’t ask, obey.

    140

  • #
    el gordo

    Beijing hacked BoM in 2015 to search for their ‘mystical secret technique’, but they found nothing.

    Any suggestion that our biggest trading partner saw BoM as the soft underbelly to breach the Defence Department, is only speculation.

    130

  • #
    AndyG55

    It is quite possible that with all their totally unfit-for-purpose climate stations and the stupidity of their urban biased homogenisation processes, that they could genuine “believe” themselves to be correct.

    I would go for bias-driven ignorance and incompetence as the main drivers of their fake temperature data.

    281

    • #
      Deplorable Lord Kek

      totally unfit-for-purpose

      and look at the empowering act:

      METEOROLOGY ACT 1955 – SECT 6
      Functions of the Bureau

      (2) The Bureau must perform its functions under this Act in the public interest generally and in particular:

      (a) for the purposes of the Defence Force; and

      (b) for the purposes of navigation and shipping and of civil aviation; and

      (c) for the purpose of assisting persons and authorities engaged in primary production, industry, trade and commerce.

      is “totally unfit for purpose” “in the public interest generally”?

      doubtful.

      and doesn’t “totally unfit for purpose” completely frustrate ” the purpose of assisting persons and authorities engaged in primary production, industry, trade and commerce”?

      probably.

      conclusion: BOM is acting ultra vires (beyond power)

      200

    • #
      Bob-l

      No the head of the climate dept at BOM is an activist, he was on their ABC this morning promoting climate change. He is the one that needs sacking. The process has “keepers” it only takes 2 keepers to keep the process in play.

      210

  • #
    George4

    BOM’s ACORN data manipulations are not to be trusted.
    Meanwhile in the US I do trust the US-CRN as being high quality weather stations.
    It shows 2019 to be the 5th coldest year since 2005 when the network started.
    https://www.ncdc.noaa.gov/temp-and-precip/national-temperature-index/time-series?datasets%5B%5D=uscrn&parameter=anom-tavg&time_scale=ann&begyear=1895&endyear=2018&month=12
    Please correct me if I am wrong, I would like to hear if I misinterpreted this.

    100

    • #
      AndyG55

      G, yep, you seem to be correct. 5th coldest since 2005, with an average anomaly of 0.01ºF

      My slowly accumulated data says the same, although some of the other years are off by ±0.01.

      Might be interesting to go back and check to see where minor adjustments have been made since original data was posted… nah.. close enough 😉

      70

    • #

      George
      You need to also mention that the USCRN, which is NEVER mentioned by alarmists, has also shown no warming since its inception.

      The BOM cut no ice with me. Their opaque methods and sudden crowing about the “hottest year ever”, the ridiculous way they screamed it was the hottest day ever whilst Sydney Brisbane and Melbourne were all below 30, if not 25, shows they left science behind long ago.

      Its simple, all they need to do is what Tony Heller does in the link below, use unadjusted temps from long term stations to show what is really happening. But that would give the game away! And it would also probably result in most of their people being unemployed, as I firmly believe most are science deniers who spend all their time working out how to present the catastrophist view regardless of what the data says.

      https://realclimatescience.com/2019/09/australia-shows-no-warming-since-1876/

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      • #
        George4

        Yes I think the unadjusted raw data gives a better indication, and it doesn’t even include the urban heat island in the city stations, which would decrease the warming trend.

        30

    • #
      Serp

      Yes, there are ten hotter years.

      20

  • #
    • #
      Kalm Keith

      Fudged?

      This summer we have had a couple of very hot days, rarely more than two in a row.

      I suspect that the data has been “interpreted” or interpolated or maybe even misrepresented.

      KK

      130

      • #
        Samsbanned

        Agree. As a child in the 50s and 60s I remember heatwaves that went for 4-5 days. Totally draining. In contrast the modern equivalent just means hiding indoors for a day or two..

        50

    • #
      Bill In Oz

      EG That chart needs some explanation
      Please !
      Bill

      00

      • #
        el gordo

        Found it in comments at Climate Etc and cannot vouch for its integrity.

        10

        • #
          AndyG55

          It is one of Tony Heller’s graphs.

          His software extracts information from the unadjusted GHCN data.

          No fiddling, no data manipulation, just the data as extracted.

          The graph heading gives you a good idea what the graph is about.

          He has filtered to a set of all long term GHCN Australian stations….

          .. then extracted the number of days above 95ºC as a percentage of all readings, on an annual basis.

          If you go to his site, you can actually download his software, takes a bit of learning,

          but the couple of times I did things using his software and compared to other far more tedious methods, I got almost exactly the same graph.

          40

  • #
    WXcycles

    Satellites are OK, as long as you recognize their intrinsic limitations. They don’t have BOM Imaginary Time-Machine-Assisted Integrated Homogenizations Technology™, nor do they have a political agenda pushing an Infinity-Crisis™, driving a media doom-complex. Thus they remain a very unreliable technology, prone to counter-revolutionary representations of unwanted facts due to excessive objectivity within primary uncorrected-datasets.

    With BOM’s methodologies they already have determined what the correct answer is in advance, making observations increasingly redundant, thus providing a welcome safety-net for when satellites get the data ideologically discombobulated. Satellites without integrated political filters or enough left-hand spin rotation calibration are particularly difficult to downplay and ignore.

    Which is why, “When the data is in doubt, BOM it!”.

    230

    • #
      Deano

      Our Bureau of Meteorology is missing a golden marketing opportunity. They could release their own brand of measuring instruments such as elastic tape measures or bathroom scales that read lower every day. Their motto: “BOM – For the results you want”

      110

  • #

    Throw another shrimp on the ACORN-SAT version 2.

    100

  • #
    OriginalSteve

    Interesting reading although it doesnt sound right…

    My inlaws recently saw a densely wooded area burn like it had petrol poured on it once the wind direction changed and picked up.

    Just let the fuel build up again…..?

    No way….

    https://www.smh.com.au/politics/federal/scientists-warn-forest-industry-plan-could-increase-fire-risk-20200109-p53q4u.html

    “But Australian National University landscape ecology expert Professor David Lindenmayer said multiple academic and forest industry studies showed forest thinning in Australia “makes forests more fire prone”.

    “”It [thinning and mechanical fuel reduction] is a misleading argument that is simply wrong,” Prof Lindenmayer said.

    “Forest and fire expert Professor Philip Zylstra from Curtin University said while thinning trees might sound like a simple way to reduce fuel loads and with it fire risk, it would actually make the forest more flammable.

    “Before thinning is used as a hazard reduction tool, there should be evidence to underpin it,” he said. “The mechanisms that drive fire lead us to expect thinning will make fires worse.

    “”Thinning trees would allow stronger winds access to fires burning beneath the trees. Also the more open a tree canopy is, the more able fire is to spread because the leaf litter will be drier from more light coming through and there will be a more dense shrub layer due to increased light for plants – that will make fires far more intense.”

    31

    • #
      AndyG55

      Sure..

      Tell that to all the National Parks and State Forests that are now in ashes. !!

      180

      • #
        OriginalSteve

        Actually, from experience when making a camp fire, putting sticks close together and blowing on a smaller fire behind them them actually helps get the fire established and actually allows the heat to be concentrated the closer the sticks are together. So logically, thinning should decrease fire intensity per square metre.

        Now extrapolate that with an 50 knot wind blowing hard amongst tall dry barked trees with flammable leaves full of oil, get some fire going and if anything I’d expect the heat to be concentrated on the trees, the closer they are together. Also, once a fire gets going, its like a fireball that pre-heats everything it its path.

        Maybe someone with more fire knowledge could flesh this out, but the Profs idea doesn’t seem to pass muster.

        It would be interesting to know whether the Profs theories have been tested under similar fuel loads, temperature & tree species.

        100

        • #
          OriginalSteve

          Actually, on the fireball comment, I suspect ( and not being a fire expert…. ) that once the air and fuel gets to a certain temp and mixture richness, I suspect a self sustaining air/fuel plasma would establish, and with internal fire air flow generated by the fire itself, would establish very high velocity ( near jet engine air velocity ) burning plasmas that would act like a blowtorch in a concrete pipe…..

          People say a fire has a roaring sound…..maybe its the high velocity airflow that’s feeding the fire that makes the noise?

          Now imagine the impact of a blowtorch of that magnitude gorging itself on all available oxygen in the area, with trees close together……

          WHOOOOOMPH!! Up it goes….

          50

        • #
          Deplorable Lord Kek

          so increasing fuel decreases fire risk, whilst decreasing fuel increases fire risk.

          extraordinary claims require extraordinary evidence and i can’t see any at link.

          there is also very strong antipathy to mechanical reduction (logging), but you don;t have to search to hard to find a contrary opinion: “Facing Deadlier Fires, California Tries Something New: More Logging” https://www.wsj.com/articles/facing-deadlier-fires-california-tries-something-new-more-logging-1542390642

          70

    • #
      WXcycles

      Most people understand that when you put twice as much dry wood on a fire the fire tends to get 3 to 4 times bigger in minutes.

      But Professor David Lindenmayer thinks this is not so.

      He thinks the leaf litter (which mostly is buried, and just smolders) will drive bigger wild fires?

      OK.

      120

    • #
      Deplorable Lord Kek

      Wait, so increasing fuel decreases fire risk, whilst decreasing fuel increases fire risk.

      A conclusion completely at odds with (eg) Royal Commission Report into Ash Wednesday: (published 2010): “The State has allowed the forests to continue accumulating excessive fuel loads, adding to the likelihood of more intense bushfires and thereby placing firefighters and communities at greater risk.”

      90

    • #
      Yalla-Y-Poora Kid

      see proof of effectiveness of reduction burns from a side by side comparison in the Gippsland fires:

      https://www.facebook.com/100002016588058/posts/2634590983284762/

      No argument possible that it does have a positive effect in reducing severity of the burn

      50

    • #
      Bill In Oz

      Ask these questions of them
      1: Where did you do this research ?
      2: When ?
      3′ Why ?
      And then ask the question : What is tree thinning ?
      It’s never been raised in any discussions before.
      Hazard reduction burns or cool burns or fuel reduction burns
      Have all been discussed widely since these fires started.
      But the academics seem to be promoting a different agenda.
      And that might be the
      Do nothing agenda of Greenies
      Who have dominated the policy for decades already !
      SUSS !

      70

    • #
      Environment Skeptic

      Another Bingo!! “Also the more open a tree canopy is, the more able fire is to spread because the leaf litter will be drier from more light coming through and there will be a more dense shrub layer due to increased light for plants – that will make fires far more intense.”

      20

    • #
      Environment Skeptic

      A healthy established old growth or native forest with a diverse species profile including evergreen tree ferns and moss/fungi at the base is a natural fire break, especially if weeds like Lantana and blackberry and other feral species have not invaded this species diversity..

      It rains in one such as this nearly every night/early morning from condensation on the leaves at night/early morning. I have done my share of camping and bush walking to verify that myself.

      I guess that is why rain forests are called rain forests although it rains without clouds in forests that are not tropical too, i would say more so.

      The leaves of 100 metre gums and shorter gums to lesser extent produce their own rainfall/climate.

      00

      • #
        • #
          Environment Skeptic

          Rivers and streams that are in old growth forest, and mature forest that still contains a good diverse native species profile that has been logged and allowed to grow back without weeds flow 365 days a year. And during drought.

          Not so in plantation forests….especially not so in juvenile plantation forests. That are taking over the country.

          10

          • #
            Environment Skeptic

            By Victorian standards, a 20 meter high gum/pine tree is still a shrub, and highly inflammable.

            Close to where i live we had fires get into the Morwel coal mine. The juvenile plantation of gums adjoining the coal mine helped it get there. The blackened plantation gums have started to regrow and the new branches do not just come out of the trees at the top/crown, they have sprouted out of the tree along the entire length of the tree down to the base creating an enormous shrubbery. The foliage is so thick it is impenetrable by humans at the moment. A machete is needed.

            The juvenile plantation is now even more flammable than when the fires went through. Not saying all plantations react this way to fire, however in general, juvenile plantation gums that survive a fire with the help of a little rain create an even greater fire hazard in a super short time due to the said growing habit of fire affected juvenile gums. In Gippsland we have a lot of rain, and plantations as far as the eye can see..

            I must take some pics and upload them to my photo sharing web application. Horror movie material.

            00

        • #
          Environment Skeptic

          Think of a blade of grass with early morning dew, only on a vastly larger scale.

          From the discussion in the abc.net.au article.

          “They certainly have an impact on temperature,” Professor Pitman said.

          Professor McAlpine’s research has also shown this.

          “Trees are a micro-climate, they cool the land surface. We’ve done a little bit of work with satellites which shows that temperatures are 2 to 3 degrees hotter in areas that have got no trees,” he said.

          “In 2003 which was a bad El Nino year, it was 2 degrees hotter over a large area of eastern Australia [due to] historical clearing.”

          00

        • #
          Travis T. Jones

          It turns out that we got this climate thing backwards. It’s not the SUVs. It’s the trees!

          2007: More Trees, Less Global Warming, Right? — Not Exactly

          A 150-year simulation of worldwide deforestation finds that tropical forests are carbon sinks and boreal forests contribute to warming –

          https://www.scientificamerican.com/article/tropical-forests-cool-earth/

          2019: Scientists Zero in on Trees as a Surprisingly Large Source of Methane

          https://e360.yale.edu/features/scientists-probe-the-surprising-role-of-trees-in-methane-emissions

          20

    • #
      David-of-Cooyal-in-Oz

      I suggest to Professor Philip Zylstra that he buys, reads and analyses a book like Joan Webster’s “The complete bushfire safety book”, first published in 1986, my version 2001. I think he’d find some evidence there.
      Or perhaps ask CSIRO about the relationship between fuel load and fire intensity. In case he’s not aware of it, even small trees add to the fuel load. But he’s an expert…
      Cheers
      Dave B

      20

  • #
    OriginalSteve

    Jo, presumably you arent likely to be impacted by current WA fires?

    30

    • #

      No. Not close to us. We live on the famous 130 million year old coastal sands with grey nutrient-free silicon dioxide underfoot. There is bush near us, but the fuel load is “only so high” limited by a lack of PNK in the soil and nearly every other mineral too.

      Farming in WA is sometimes known as hydroponics and we live on soil worse than that.

      110

  • #
    Zigmaster

    When one looks at the fires the temperature of Australia is irrelevant if one doesn’t see the individual data that makes the record. My observation of the weather in Melbourne and Sydney is that the actual temperatures have been modest and having checked the figures there hasn’t been a period of 3 days in a row over 30 in the last few months when the bushfires have occurred. It would be interesting to see what the temperatures are in the fire region I suspect that they would be more moderate than portrayed by the BOM. A record claimed for Australia could be due to higher temperatures in the Kimberleys or Darwin or Alice Springs thousands of miles from where most of the fires are. It’s like claiming that the fires in Italy are caused by the fact that it’s getting hotter in Europe. When the temperatures between Broadmeadows, Portsea , Cranbourne and Warrigal vary by anything up to 4-5 degrees on any day it tells you that the size of the claimed temperature increase is actually petty irrelevant to increase in fire risk. I get very frustrated when I hear of these record claims when my eyes and all my senses tells me that it is not true.

    101

    • #
      Geoff Sherrington

      Zig,
      We have known this for years.
      For example, search Jo’s site for “Sherrington Heatwaves” or the like.
      You’ll find it all there.
      For the official claim that heatwaves are becoming hotter, longer and more frequent, look at the graphs for the 6 main capital cities and conclude that in most cases this is false. That is using just simple math on official BOM data.
      It distresses me a little that right now, there is so much posted on Jo’s site that is relevant, but unread or unremembered by the readers of today.
      You guys should be working hard to keep these old data compilations up to date in 2020. They took a long time to create, many hours of unpaid voluntary work, and now they sit unused and unloved.
      Please put some effort into keeping them current. They are compelling and so difficult to deny. And they are dead straight, no agendas or questionalble adjustments, no cherry picking.
      Geoff S

      00

  • #
    chrisl

    A note from a friend in The Netherlands . The English is a bit mangled but the message is familiar…

    Here in NL we have several discussions about reliability of KNMI (meteorology) and RIVM (public health). Both scientist organisations. Scientists are not the people we hear. Scientists have mostly in these kind of organisations a boss, who is not a scientist, but a manager. With responsabilities about costs and incomes.
    Scientists at KNMI knows that the story of that one scientist is very much worth it to investigate. But they are not allowed by their boss even to discuss about it.
    RIVM is an organisation which is measuring CO2, nitrogen and amonia. But not able to tell how numbers are calculated, so it is not possible to reproduce and argue with the results.
    In the mean time, politics starts discussions, making rules and laws, based on these organisations. With huge economic (disasterous) effects.
    About CO2, this discussion was started by Al Gore. He is no scientist. Since then, the discussion vs dialog about the oceans (and other influences) allmost stopped.
    My worries about it, has to do with the effect. What if we change our lifestile to prevent CO2 and in about 10 years we see it only became worse because it is not the cause of all of this…
    I miss the dialog.
    I am also not convinced the scientists leads the discussion.

    160

  • #
    Matt

    My biggest dislike of the BOM is their constant talk about a warming climate that feeds the climate crisis frenzy. It is just wearing people out. The constant fear monger actually affects people psychologically and affects families. Children are now pitted against their own parents. How does this help anyone? How does it meet their legislative charter? If there is a Royal Commission into the bushfires the performance of the BOM should be inside the terms of reference.

    230

    • #
      davefromweewaa

      Plus a hundred Matt!
      Trewin and Jones should be on the inside looking out for the damage they have done.

      30

  • #
    pat

    o/t except you can’t believe anything when it comes to the CAGW mob:

    read all:

    9 Jan: EnergyVoice How second industrial revolution was cast to the wind
    by Brian Wilson
    (Brian Wilson is a former UK energy minister)
    On the Friday before Christmas, the last of 140 workers at the Arnish fabriction yard on Lewis were paid off.
    It was a metaphor for renewables manufacturing in Scotland and failure to turn opportunity into the “second industrial revolution” once promised by Alex Salmond…
    Two days before Arnish closed yet again, the Scottish Government published its latest consultation paper on the future of offshore wind. It asks why so little of the work is coming to Scotland…

    On the day the Scottish Government consultation paper was published, it was reported that SSE was to send the vast majority of work on the Seagreen offshore wind farm overseas, including to China where health and safety standards are presumably to its satisfaction
    Gary Smith, Scotland secretary of the GMB union, said: “This would be the death knell for any meaningful offshore wind manufacturing industry in Scotland – an utter scandal and a national disgrace”. Just as at Arnish, the gap between reality and “aspiration” is as wide as ever.
    https://www.energyvoice.com/opinion/215398/how-second-industrial-revolution-was-cast-to-the-wind/

    50

  • #
    Richard Ilfeld

    Sometimes it is necessary to be cruel to be kind.
    One would hope there is a philanthropist would establish a museum in Australia.
    It would honor the species at risk and entities killed in the latest fires.
    The start would be a paen to the environmentlist bleatings about retaining the virgin forest
    “for the preservation of species, and biodiversity” and other high minded causes.
    The end would be a display of urns of ashes, as those to be preserved were killed due to fires much hotter and less controllable
    than those that came before.

    The left cares so much, that they often kill that which they profess to love, whether the forest primevil, or the
    quaint neighborhoods of downtown San Francisco. They will love a town so much as to zone an economy out of existence,
    they will love a park so much that it will become unusable, and, in the end, they will love freedom so much that it will totally disappear.

    Perhaps the evidence that they detest climate skeptics is not a bad thing.

    70

    • #
      David-of-Cooyal-in-Oz

      You may find this letter from Today’s SMH interesting. The author doesn’t seem to recognise that all, or at least most of the animal fatalities have occurred in the sort of areas she’s promoting, called National Parks. But she does read the SMH, and get published, so she must be a believer and, of course, fully informed by SMH coverage.

      Out of all the millions of dollars donated towards bushfire relief could a respectable portion be used to buy and establish land suitable for re-establishing our wildlife or what is left of it? So much native habitat had already been destroyed in the name of progress/development before these fires. Now is the time to halt any further destruction; now is the time for the Premier to announce that areas such as Wedderburn, where there is an established koala colony, will be saved and, if possible, expanded. We can replace homes and trees but we cannot replace our unique and marvellous wildlife once it is extinct. – Nola Tucker, Kiama

      Cheers
      Dave B

      00

  • #
    Deano

    I was wondering where the annual “Hottest Year Ever” announcement would be made as I always look forward to it like the start of the footy season or first really soaking rains of winter. It’s amazing how predictable the year after year rise in average temperature is these days. When you look at those un-doctored graphs of global average temperatures from just a few decades ago with those nasty random falls and rises, you realise how lucky we are now to have a climate that is predictable with a simple graph.

    30

  • #
    Vishnu

    And we’re off to the races ! Conspiracies to the right of them and to the left of them.

    Dr Roy Spencer one of the beloved UAH satellite series publishers himself has commented on the issue. Alas not reported by the resident hatchet wielders. But so predictable.
    https://www.drroyspencer.com/2019/04/australia-surface-temperatures-compared-to-uah-satellite-data-over-the-last-40-years/

    We could, of course, discuss the many “adjustments” to the satellite data – but hush my mouth. Why get all sciencey.
    Hey I wonder if the sceptics with so much time on their hands have done their own analysis – nah won’t happen.

    619

    • #

      Thanks for the link Vishnu, and here’s one back for you.

      Satellite battle: Five reasons UAH is different (better) to the RSS global temperature estimates

      Just in case you were thinking we weren’t aware of the UAH adjustments and why it’s still the best data set in the world.

      28 million radiosondes agree…

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      • #
        Vishnu

        Jo – we weren’t discussing RSS. Was that a rabbit that just trotted past. You could make the same argument for sondes vs surface. Clearly Roy’s discussion didn’t sink in.

        This Oz surface temps vs satellites is just a ruse argument. And why would you be comparing UAH to an homogenised surface temperature data set (spits on ground) you don’t believe in and think is just stats hooey.
        Until sceptics do their own surface analysis – and how hard could it be if rocket scientists are aplenty and one deck? Acquire copy of ADAM from BoM. Delete the Ken Stewart hit list of yuck stations. Assume a few left. Bit of R and Python hacking. Maybe some Dask for good measure.

        I put it to you that it’s not in your interest to do such an analysis in case it mirrors the mainstream – wouldn’t that be a bugga. Easier to nitpick.
        Come on do the rolled gold alternative analysis – until then – https://www.youtube.com/watch?v=gKosmXx1gkc Golly I’m even curious. Surely you must be too?

        P.S. Love your site even if some of the inmates are a bit feral.

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        • #

          The whole point is to show the beat-ups and slanting. Invitations to set up as an alternative BoM are like those kind invitations to get published. We all know those are invitations to pound sand. (Good try though!)

          Global warming – real, contrived or magnified – is an utter triviality. Temps can only do two things. They have never been known to tap dance or whistle Dixie. They just go up or down in various lines and cycles.

          If temps have been rising and if there has been a dribble of sea level rise since the 1700s that is to be expected and is of no importance. As to the indications of higher sea levels in periods as recent as the 1500s, and as to the severity of that last cooling episode around 1700…those are matters of some importance when we consider that the present beating up and slanting of climate information is one way traffic.

          Ignoring most geology, stratigraphy, glaciology, speleology, oceanography, archaeology and history in the service of a fashionable dogma is no way to run a civilisation. Someone needs to tell the globsters that their long-desired shriveling of humanity will come soon enough when the Holocene declines like every other interglacial. Why the rush?

          80

          • #
            Vishnu

            So you’re the slightest bit curious on what a “sceptic approved” temperature analysis would look like? Wow!

            16

      • #
        Peter Fitzroy

        It (UAH) does not measure mountains – but no deniers will ever mention that

        17

      • #
        Peter Fitzroy

        Also what version of UAH is being used? is it 1,2,3,or 4
        What is the methodology between the instrument and the final result?
        is that methodology published?
        is the original data published?
        Who decided to alter the results?
        What is the reference value?
        how is the reference calculated?

        See UAH has as many problems as the SAT – but deniers will never mention that either

        18

        • #
          AndyG55

          UAH v6, scientific adjustments due to KNOWN empirical changes in satellite orbits

          Yes

          It comes from many satellites including NASA’s, go ahead and find it yourself.

          Results are adjusted to compensate for KNOW changes in satellite movement.

          Reference is stated in UAH files.

          UAH has far fewer problems that the whim adjusted, sparsely and irregularly spaced unfit-for-purpose surface data

          UAH is verified again balloon data, and pristine surface data over the USA.

          Sorry if all this is beyond your comprehension.

          50

      • #
        Peter Fitzroy

        And those 28 million radiosondes and UAH – why wouldn’t the agree? neither are measuring SAT now are they? But to maintain agreement UAH must be adjusted – so much for a gold standard

        18

        • #
          AndyG55

          Nothing properly measures the SAT. !

          There has been no change in the atmospheric lapse rate, the surface should have the same trend as the surface .

          There is no energy being “trapped” in the atmosphere as shown by the OLR vs atmospheric temperature.

          80

          • #
            Peter Fitzroy

            ALR now – getting desperate are we? Making assertions not backed by any science?
            SAT and Tropo can not be compared as they are measuring 2 different things . Both are adjusted, both can be questioned, unless, of course you are a denier

            19

            • #
              AndyG55

              So you admit you know nothing about OLR. Thanks.

              I have posted that data many times.

              There is no reliable untainted measurement of surface data. Period

              Surface data is a monumental farce.

              Sorry you don’t have the capacity to understand the difference between agenda driven adjustments (surface data) and scientifically driven adjustments (Satellites)

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            • #
              Depolrable Lord Kek

              Both are adjusted, both can be questioned

              oooh, so the science is not settled.

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        • #
          AndyG55

          Seems Peter doesn’t have a clue about using reference data to make scientific adjustments for KNOWN perturbations in satellite orbits.

          The whole idea is incomprehensible to him.

          22

        • #
          R.B.

          Compare HadCRUT4 with UAH6
          http://woodfortrees.org/plot/hadcrut4gl/from:1978/detrend:0.4/plot/uah6
          After defending so that the line of best fit are the same. They measure the same thing, almost, with the difference being due to a systematic error in one or the other, or both.

          Try looking at the data, Fitzy.

          10

    • #
      AndyG55

      So Roy is saying that temperatures in the station data have a zero trend this century, is that correct?

      Because that is what UAH says

      And over the USA, apart from the surface USCRN data responding more to El Nino and La Nina effects,

      UAH USA48 pretty much matches USCRN.

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    • #
      AndyG55

      Roy’s “adjustments” are very carefully made by necessity due to KNOWN shifts in the satellites.

      A far cry from BOM and NOAA data adjustments, which are based more on whim and bias driven speculation.

      120

      • #
        Vishnu

        Ah you wouldn’t know jack about remote sensing. “Carefully made” LOL – mate they got it wrong and had to redo it – hahaha. It’s in the literature. Do some reading in 2020.
        If you did you could be a decent scepo instead of a tiz tisn’t guy.

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        • #
          AndyG55

          No they didn’t , They found one of the satellites had moved from its orbit.

          That is not getting it wrong, that is correcting for a KNOWN measurement error

          You really do need to keep up and try to understand things, Vishnu

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  • #

    […] On Thursday 9th the Bureau of Meteorology released a statement that 2019 was Australia’s hottest year on record. Jo Nova used the most reliable source of information since 1979, the satellite monitoring system, to produce this picture of the annual temperatures. Read the full story. […]

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  • #
    Graeme Bird

    Hey but didn’t Heller already show that this data is dirty?

    30

  • #
    Graeme Bird

    Okay so its the Australian data. As long as you are sure.

    10

  • #
    Samsbanned

    Jo and David Evans
    Just when you thought you’d heard everything about it –
    Check out this bizarre gem

    https://www.spiritualresearchfoundation.org/spiritual-research/global-issues/climate-change-causes-and-solutions/

    I’ll grant them one thing, at least they say the human contribution is only 19%. For a ref glooge ‘mayavadi’ (disguised atheism; most Buddhism is of a similar vein), or ‘impersonalism’; that’s what these folk are all about.
    I especially like the part about agnihotra (fire sacrifices) affording protection from fallout in the event of a nuclear WMD event. Seriously, ha ha

    10

  • #
    AndyG55

    Roy Spencer on Australia fires.

    1) Global wildfire activity has decreased in recent decades, making any localized increase (or decrease) in wildfire activity difficult to attribute to ‘global climate change’.

    2) Like California, Australia is prone to bushfires every year during the dry season. Ample fuel and dry weather exists for devastating fires each year, even without excessive heat or drought, as illustrated by the record number of hectares burned (over 100 million) during 1974-75 when above-average precipitation and below-average temperatures existed.

    3) Australian average temperatures in 2019 were well above what global warming theory can explain, illustrating the importance of natural year-to-year variability in weather patterns (e.g. drought and excessively high temperatures).

    4) Australia precipitation was at a record low in 2019, but climate models predict no long-term trend in Australia precipitation, while the observed trend has been upward, not downward. This again highlights the importance of natural climate variability to fire weather conditions, as opposed to human-induced climate change.

    5) While reductions in prescribed burning have probably contributed to the irregular increase in the number of years with large bush fires, a five-fold increase in population in the last 100 years has greatly increased potential ignition sources, both accidental and purposeful.

    “So, to automatically blame the Australian bushfires on human-caused climate change is mostly alarmist nonsense, with virtually no basis in fact.”

    Basically backs up everything we have been saying.

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    Simon

    Satellites measure irradiance as a proxy which has to be then calibrated to temperature. The temperature estimate is for the troposphere, not the earth’s surface. We do not live one kilometre up in the atmosphere.
    Why are these caveats never mentioned by people who love quoting UAH because it shows less warming than surface thermometer measures? It’s downright dishonest.

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    • #
      el gordo

      Not sure it matters, we are looking for a trend to rely on, data we can believe in. A BoM audit is essential and they could include Roy’s effort as a control.

      61

    • #
      Deplorable Lord Kek

      According to the anthropogenic global warming hypothesis, the lower troposphere is supposed to warm at a faster rate than the surface.

      50

    • #
      AndyG55

      No, its simple, simon.

      People quote UAH because it id basically free from agenda driven data corruption and mal-adjustments.

      That, of course, means it is more likely to be closer to reality.

      In Australia, it is absolutely certain that UAH will be closer to reality, because it has been shown that a very large proportion , some 40% iirc, of climate stations are basically UNFIT FOR PURPOSE>

      Using BOM or GISS data is the thing that is downright dishonest.

      60

    • #
      AndyG55

      The other good thing abut taking temperature trends in the troposphere away from urban areas is that it essentially negates urban warming at unfit-for-purpose temperature sites.

      This gives a far more realistic estimate of any actual real warming.

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    • #
      R.B.

      Satellites measure the irradiance for the whole country. The temperature anomaly from this is still a reconstruction from the raw data like the thermometer readings. I’ve checked some of the BOM maps shown of Australia with its record heat in previous years and there are areas bumping up the average that actually have zero data within them, or one station with barely any data in the base period. These are just pure guess work and guess what, they end up being the hottest regions (above the average).

      Checking up on whether a mean of max and min are comparable to the mean of continuous readings during the 24 h, I’ve noticed something that strongly suggests that you should go with UAH just because they are more honest.

      20

  • #
    Maptram

    The Deniliquin Information Centre BOM site operated from about 1858 to 2003 with a two year year gap in the 1860s. The Airport site, about 4 kms away opened in June 1997 and still operates today, so the two sites can be compared for 1997 to 2003. In looking at the data where the records overlap, I noticed that the Airport temperature data until 2003 is recorded in whole numbers while the Info Centre data is recorded to 0.01°C. I don’t know whether the airport 1997 – 2003 data was rounded up or down to whole numbers. Makes me think that perhaps the BOM was providing weather data at airports for airport landings and takeoffs, rather than as part of the weather record and did not require the same quality. Perhaps as a cost cutting measure they closed the Info centre site and now provide data for both purposes from the airport site. Nevertheless, the airport data is now part of the data record and most of the 1997 to 2003 data has passed quality checks, based on the the BOM disclaimer.

    I expect that there would be similar situations at other airports throughout Australia.

    00

  • #
    min

    Geologist friend, Dr Howard Brady, who wrote Mirrors and Mazes that explains past history of climate ,discovered remains of trees in swamps in south coast NSW that are now found only in Tropical Queensland,
    Since all the rubbish about indigenous farmers and stone houses in villages has been published I point out it must have been hotter before First Fleet as no one needed clothes ,only the odd possum cape down south. I have visited many indigenous tribes around this planet Masai in Serengeti and northern Kenya Inuits in Canada Indians in America all had clothes out of necessity They all learnt how to clothe themselves to protect from weather not our mob though .
    Jacinta Price has something to say about this.
    Sir John Monash also wrote about severe drought in 1874 a when he was a young boy living on Border of Victoria and NSW.

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  • #
    Simon

    The BoM has, in my opinion, assembled the best national temperature data in the world because they use the most advanced methods to correct for known problems, like moving a recording station to another location or installing a new instrument. The process is called “homogenization” because its goal is to create a temperature record which reveals what happened other than those things irrelevant to climate (like moving the station or changing the instrument). They also use advanced methods to detect such discontinuities; the BoM really does an impressive job. Australians should be proud.

    https://tamino.wordpress.com/2020/01/06/bushfire-and-homophobia/

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    • #
      AndyG55

      Tamino’s opionion. ??

      Now that’s funny. ! 😀

      And probably the most worthless opinion on the planet.

      50

    • #
      AndyG55

      Around 40% of site BOM uses do not come even close to meeting their own requirements for lack of bias.

      In fact some are so bad as to be totally ludicrous.

      But they still use them. 😉

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  • #
    Travis T. Jones

    Satellites v surface air temperatures v sea surface temperatures; the ‘settled science’ of UN 97% global warming …

    – “But Mann, Dessler, Francis and others say there have been quality and trustworthy issues with some satellite measurements and they only show what’s happening far above the ground.
    They said ground measurements are also more important because it is where we live.”

    http://pittsburgh.cbslocal.com/2015/01/16/scientist-say-2014-hottest-year-on-record-but-not-in-pittsburgh/

    – “This is only the global average surface temperature and it’s only one measure of the climate system – and it’s a very fickle measure.
    There’s an over-emphasis on the surface air temperature. “- Prof Matt England.

    https://www.theguardian.com/environment/planet-oz/2016/mar/03/did-global-warming-really-slowdown-have-a-large-injection-of-nuance-and-a-side-order-of-abuse

    Gavin Schmidt:
    “That’s not to say the satellite measurements don’t provide some value, but it is an indication why the surface temperature data analyzed and reported by NASA, NOAA and others is viewed as the gold standard.”
    https://www.climatecentral.org/news/what-to-know-februarys-satellite-temp-record-20091

    Now, Stephen Briggs from the European Space Agency’s Directorate of Earth Observation says that surface air temperature data is the worst indicator of global climate that can be used, describing it as “lousy”.
    https://www.theguardian.com/science/2014/jun/13/pause-global-warming-data-sea-level-rises

    NASA: “There is far too much focus on surface temperatures.
    They are but one measure of warming. All other measures . . . continue unabated.”
    https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/04/14/nasa-smacks-down-climate-change-doubters-in-facebook-discussion/?postshare=7041460656502892&tid=ss_tw

    “Most people are not fish, most people live on land,” Professor Karoly said, noting that the sustained warming over land had been about 40 per cent more than over the oceans.
    https://www.smh.com.au/environment/climate-change/worse-things-in-store-steaming-hot-world-sets-more-temperature-records-20160420-goaf58.html

    20

  • #
    Peter Fitzroy

    How is it that you can compare measurements of 2 different things (SAT and Troposphere), one of which only goes back to the seventies, and then make such a declaration?

    So what if the tropo measurement (which ignores mountains) is only in 4th place.

    Another stupid comparison, valuless in all aspects.

    27

    • #
      Travis T. Jones

      “Another stupid comparison, valuless in all aspects”

      Stupid NASA: “There is far too much focus on surface temperatures.
      They are but one measure of warming.
      All other measures . . . continue unabated.”

      https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/04/14/nasa-smacks-down-climate-change-doubters-in-facebook-discussion/?postshare=7041460656502892&tid=ss_tw

      Denial is not just a river in Egypt.

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      • #
        Peter Fitzroy

        I’m sorry but that link does not work on my page.

        but you miss the main point (deliberately like all deniers). this is apples and oranges – it is dishonest and a crude attempt at that.

        07

        • #
          AndyG55

          Still no evidence that the slight, but highly beneficial, warming since the LIA has been caused by human released atmospheric CO2.

          We live in the Modern Slightly Warm Period.

          Ocean warming cannot come from atmospheric CO2.

          Can come from decreased tropic cloud cover, though.

          Atmospheric CO2 does not “trap” any energy or warm anything.

          And you cannot produce any real scientific evidence that it does.

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    • #
      AndyG55

      So are you saying that there has been a change in the atmospheric lapse rate.

      That is the only thing that would cause a divergence in atmospheric and REAL surface temperatures.

      Problem is that there is no reliable, untainted measurement of surface data anywhere except in the USA as USCRN

      And it matches UAH very closely.

      30

      • #
        Simon

        Codswallup. You only need about 30 accurate stations to determine a statistically significant mean.
        Homogenisation techniques are well understood and statistically verifiable.
        The test is that all the surface measure estimates: NOAA / GISTemp, HadCRUT, BEST, JRA show virtually the same annual anomalies. The outlier is UAH, and it keeps getting readjusted.

        26

        • #
          AndyG55

          LOL, they are all based on exactly the same unfit-for-purpose source data. !!

          Except BEST, which gathers in a whole heap of even worse data.

          Yes, homogenisation processes are well understood.

          It matches and adjusts the few bits of data from untainted sites to the corrupted and urban affected data from the unfit-for-purpose sites.

          If anything, the process makes the whole procedure WORSE, not better.

          It also totally corrupts any real information that might have been in the original data.

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        • #
          Graeme No.3

          Simon:
          I agree with your commet being codswallop. Where would you find 30 accurate stations in Australia?
          At least 45% of BoM stations do NOT comply with the specifications set by the BoM.
          And no doubt the figure will rise as Ken continues his work examining the others. And even if he finds a station that is compliant, it would probably be “homogenised” with data from a station (or 2 or 3) a few hundred kilometres away.

          And speaking of HadCRUT have these adjusted those 2 stations (in Columbia) that were showing temperatures above 80℃ for 2 months? Or the tropical island in the West Indies with a month averaging 0℃ ? What were you saying about outliers or did you mean OUT LIARS?

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    • #
      AndyG55

      “which ignores mountains”

      Another inane comment from Peter,

      Totally without value or content.

      Shows he has zero comprehension of trends and how they work.

      Satellite measure a stable fixed grid (apart from satellite drift which can be scientifically compensated for)

      There is no measurement of surface temperature which is not totally compromised by huge urban warming effects, sparse and irregular stations settings , massive changes in actual station locations and surrounds and equipment.

      There is just no reliable, untainted surface data temperature record

      It is in fact an impossibility for one to exist.

      Only USCRN, which only goes back to 2005, come close to being satisfactory, and it matches the UAH USA48 satellite data quite closely.

      The whole surface station temperature farce needs to start all over like USCRN.

      But that will never happen, because people like BOM, GISS etc are content to use the worst data available, because it helps them push their AGW agenda

      30

    • #
      AndyG55

      Satellites measure a stable fixed grid (apart from satellite drift which can be scientifically compensated for)

      There is no measurement of surface temperature which is not totally compromised by huge urban warming effects, sparse and irregular stations settings , massive changes in actual station locations and surrounds and equipment.

      There is just no reliable, untainted surface data temperature record

      It is in fact an impossibility for one to exist.

      Only USCRN, which only goes back to 2005, come close to being satisfactory, and it matches the UAH USA48 satellite data quite closely.

      The whole surface station temperature farce needs to start all over like USCRN.

      But that will never happen, because people like BOM, GISS etc are content to use the worst data available, because it helps them push their AGW agenda

      [No idea why this was caught. The filter looks at combinations so if you think it should be OK then you did the right thing.] AZ

      20

  • #
    Simon

    Over at WUWT, Roy Spencer is making the peculiar argument that greenhouse gases can’t be the cause of 2019 Australian record temperatures because they are higher than the CMIP model predictions. He is choosing to use surface temperature data, not UAH.

    25

    • #
      AndyG55

      Its simply WEATHER, simon.

      Please learn to tell the difference.

      Surface temperature data, as we all know, comes from unfit for purpose urban and airport sites, and what do you thing might be recorded at such sites during a fire storm like we have had.

      No, it’s simple, Simon, We have had 3 years of very deficit rainfall, in an increasing rainfall trend.

      That has cause exceptional loads of very dry fuel.

      A bonfire waiting for a spark… and apparently lots of sparks available, human and otherwise.

      WEATHER not climate

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    • #
      el gordo

      We already know the surface temperature is dodgy.

      ‘It is somewhat peculiar that the Bureau did not recognise, in its process of remodelling the historical data for Rutherglen, that the summer of 1938-1939 was exceptionally hot because of drought, compounded by bushfires. Rather David Jones and Blair Trewin at the Bureau used the exceptional hot January of 1939 as an excuse for remodelling the historical temperature record at Rutherglen, with the changed values subsequently incorporated into international data sets.’

      Jennifer Marohasy

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    • #
      DavidGeo

      Roy publishes the UAH data each month on his website. My understanding is that Roy Spence is saying, is that based on the BOM’s own data that Australia is warming at a far faster rate than that predicted by the 41 CMIP5 models which are known to be over-sensitive to warming (tropical predictions versus observations). It means Australia is warming faster than the rest of the World. Global warming? Australia warming? Or Natural variability?

      50

  • #
    DavidGeo

    BOM has always acknowledged the weakness of in situ measurement versus use of satellite and radar temperature data. When BOM released the new gridded data set in 2009 they stated “In constructing these new climate data we have deliberately used only in situ data managed by the Bureau of Meteorology. We recognise that rather better analyses are possible for recent years, drawing on remotely sensed information from satellites and radar. However, these newer data types typically
    do not go back far in time, and even long-run data such as infrared data from geostationary satellites show large and systematic shifts in resolution and quality arising from multiple changes in satellites, orbits and instrumentation.” The same could be said for site changes and changes in instruments at the current weather stations. Yet they persist with a gridded data set with limited data points particularly in remote areas (typically desert) and kringing methods which introduce significant measurement errors. Robustness and data quality is surely at question.

    Ref: Jones et al, High-quality spatial climate data-sets for Australia, Australian Meteorological and Oceanographic Journal 58:4 December 2009

    30

  • #
    Maptram

    One problem with the BOM data is that they provide observations over a three day period, usually half hourly, but sometimes at airports more frequently, and the observations are removed after three days. The Climate Data Online site shows the minimum and maximum temperature for each day. Maximum temperatures are always between 0.1 and 1.5°C higher than observed temperatures, and minimum temperatures are usually lower than observed temperatures, but no time is shown.

    This means that in some half hourly period each day, the maximum temperature has spiked by up to 1.5°C, and dropped by up to 1.5°C or more, but no one knows when because the Long Term Data doesn’t show a time.

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  • #
    William

    This is anecdotal I know, but I judge Sydney weather by our use of fans and our one heater. Last year the heater was still upstairs in November and so far this summer, we have not brought the fans up from the garage – we are fortunate to live close to the harbour and get the sea breeze. Previous summers, notably 2003 and 2005 we were considering getting airconditioning due to the heat, and we were shutting our place up and closing the curtains to keep the cooler air inside during the day.

    So yes, there is nothing scientific about it, but over the past few years, we have used our heater for longer and our fans less in summer. Interesting Jo’s satellite graph continues to show no warming for the last two decades.

    20

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    Zane

    Guardian says ” global heating ” is impacting Mt Everest. Yikes! The bad news never stops… according to the Guardian. Tomorrow it will no doubt be time for another Great Barrier Reef bad news story…

    40

  • #
    Kim

    Urban Heat Islands – hot spots in cities – that’s where the heat is. Solar IR -> concrete & tarmac -> heat.

    30

  • #
    DonS

    Hi Jo

    I’m not going to buy into the argument between satellite and surface temp measurements except to say that as CO2 is in the atmosphere that is where the warming should be seen. No hot spot in the atmosphere suggests that readings from however many surface stations may be a poor proxy for what is going on in the planetary climate system.

    Anyway with regard to the annual hottest year since forever and ever that the BOM and ABC get very excited about, but only in summer, each year. Why do they only go back to 1910? Could it be that is because the decades from 1870 to 1910 were actually the hottest and driest measured? Even if you assume people were dumber back then and had less accurate equipment the records seem to clearly indicate times were pretty hot.

    Also why do they compare the average temp last year to an average of the years 1961 to 1990? Was it not the case that there was a fall in global temp
    between 1945 and 1975? Why take the average from the middle of the cooling? Why not from say 1975 to 2005? I suppose people will take the average from whenever it best suits their case, lies and statistics, unfortunately few people seem aware of the tricks used by government funded bodies to push an agender favourable to them.

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    • #
      Tinkerbell

      I’m not sure what you mean in your first paragraph. The satellite temperatures are measured using remote sensing techniques and involve calibrations that are quite complex. Therefore what is measured by the satellite is not the same as what is measured on the ground.

      In your second paragraph the answer to your second question is a definite ‘No’. Early climate observations were limited in time and in space and the instruments used to take measurements was not standard prior to 1910. The ‘less accurate’ equipment does not reflect on people’s dumbness either. They used what was considered best at the time. By 1910, taking measurements was standardised. For example you don’t want to have a measurement of rainfall being taken next to a sprinkler, or a measurement of temperature being taken next to a barbecue.

      With respect to the reference temperature that is used to compute averages, this page (http://www.bom.gov.au/climate/how/newproducts/map-periods.shtml) explains the rationale. However, please note that when computing averages compared to a reference base period, it does not really matter in the end what period you choose. If you choose a different period when temperatures were cooler, then the other warmer temperatures will just appear even warmer and cooler ones less cold than if you choose a different reference period. So whatever reference period you choose, the conclusions you arrive at are the same. What you are doing is simply comparing temperatures to a reference period which can be any period you want. If you follow the link I point to, you will see that 1961-1990 is the reference period chosen by WMO to maintain consistency worldwide.
      If another period had been chosen, the trend towards higher temperatures for the more recent times would still be there. The result would be the same. You can choose 1945 to 1975 or 1975 to 2005, the warming trend would still be there regardless of what period you choose.

      The BoM has no need to push any agenda. Its function is to maintain a climate record, produce forecasts and weather and flood warnings. It will still do that whether the Earth warms or cools.

      People will ask questions why does the BoM do this, why does it do that and they think because the BoM does not answer (it does not monitor blogs like this) that what it is doing is incorrect. But if you really knew how these things are done (and it is not always possible to answer these questions simply) you will realise that there is a good objective reason why the BoM does things the way it does.

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      • #

        No Tinkerbell. We’ve asked the BOM. It has answered, or been forced to answer, and it has admitted it cannot explain its methods in full. If it can’t be replicated, it isn’t science.

        http://joannenova.com.au/2015/06/if-it-cant-be-replicated-it-isnt-science-bom-admits-temperature-adjustments-are-secret/

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        • #
          Tinkerbell

          Your response is about the ACORN SAT. I was trying to explain why the early observations can’t be used and also why the reference temperature period chosen does not make any difference to the trends.

          The ACORN-SAT work the BoM did was reviewed by a panel of experts and found to be of high quality.
          There was a lot of work involved and it is not possible to go into every minute detail of the work. It took a long time to develop and would take even longer to explain every detail.

          Furthermore, the trend in warming overall using the unadjusted dataset is higher than that using the adjusted dataset. What would have been the point? In any case, the original unadjusted dataset is available for the public (and it shows a stronger warming trend overall).

          01

          • #

            Tinkerbell,

            1. Many early observations are better than current ones.There were Stevenson screens in some places from the 1880s onwards and little UHI. The BOM threw out a hottest ever record recorded in a Stevenson Screen in 1909. They did 60 years of comparisons with other screen types, so some older records can be compared if only the BOM thought the climate was important. New screens are often junk — non-compliant with the BOM’s standards, recorded in different equipment, electronically, with “one second records” which are meaningless compared to glass thermometers. The BOM doesn’t care about thermometers near skyscrapers or over bitumen for 30 years, and yet they are precious about the better cleaner records 120 years ago. If those records were cooler, they would be interested.

            The ACORN SAT review was a waste of time — didn’t even review the key allegations raised by skeptics. Designed to be a whitewash that gullible fools could quote to fog up the debate.

            “Can’t explain the details” = is not science.

            “A lot of work” means we the people were ripped off, we paid for that and got nothing but propaganda and b-grade wishful thinking.

            As for the “trend in warming” — you are kidding, deceived, or lying outright. The raw data supports skeptics. The adjusted data is almost always “non randomly” adjusted to match models in every single data set.

            I can understand why you want to stay anonymous. Best hide your identity.

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      • #
        Kalm Keith

        “you will realise that there is a good objective reason why the BoM does things the way it does.”

        I totally agree, and there are in fact two reasons;

        Power and Money.

        KK

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  • #
    Vishnu

    This is a bit inconvenient for sceptics

    Roy Spencer says in my link above.

    “The UAH tropospheric temperatures and BOM surface temperatures in Australia are correlated, with similar variability (0.70 correlation).
    Accounting for anomalous rainfall conditions increases the correlation to 0.80. ”

    So if BoM’s analysis is so crook you’d expect no correlation. But it’s very good. Not perfect but very good.

    Lessons – yep Aussie does seem to be warming.

    Now this is really critical for Ken Stewart to do a rolled gold (no homogenisation here – we’re British) sceptics analysis. Then we could be informed instead of just lobbing rocks.
    I reckon will show warming trend (2/3rds BoM’s) but not as much. Don’t yo’all want to informed.

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      Yep. We can rely on Vishnu for more distraction and red herrings.

      The big deceit in the BOM records occurs 100 years ago or more with cooling adjustments as large as 2C.

      Not too many satellites then. Doh.

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