Blockbuster: Are hot days in Australia mostly due to low rainfall, and electronic thermometers — not CO2?

Blame dry weather and electronic sensors for a lot of Australia’s warming trend…

In this provocative report, retired research scientist Bill Johnston analyzes Australian weather records in a fairly sophisticated and very detailed way, and finds they are “wholly unsuitable” for calculating long term trends. He uses a multi-pronged approach looking at temperatures, historical documents, statistical step changes, and in a novel process studies the way temperature varies with rainfall as well.

His two major findings are that local rainfall (or lack of) has a major impact on temperatures in a town, and that the introduction of the electronic sensors in the mid 1990s caused an abrupt step increase in maximum temperatures across Australia. There will be a lot more to say about these findings in coming months — the questions they raise are very pointed. Reading, between the lines, if Johnston is right, a lot of the advertised record heat across Australia has more to do with equipment changes, homogenisation, and rainfall patterns than a long term trend.

Bill Johnston: On Data Quality [PDF]

“Trends are not steps; and temperature changes due to station changes, instruments and processing is not climate change”, he said. “The Bureau are pulling our leg”.

The years when more rain falls are more likely to be years without high maximums. Bill Johnston finds that for every 100mm of rainfall, the maximum temperatures were about a third of a degree cooler.

Australian Temperatures, adjustments, homogenisation, Bureau of Meteorology, BOM

On the left hand side, the step ups in temperature are shown. Electronic sensors were introduced in the mid 1990s. The right hand graphs show how rainfall keeps maximum temperatures cooler. (Data is grouped “a,b,c” between the steps).

Johnston uses these rainfall correlations as a tool to check the quality of temperature records. When combined with step change analysis, he finds that unrecorded site moves or station changes are common. When the automatic sensors were introduced temperatures suddenly jump up, and their relationship with rainfall breaks down.

“Fleeting parcels of hot air, say from passing traffic or off airport runways, are more likely to be sensed by electronic instruments than by thermometers”, he said. 

Automatic weather stations (AWS) were introduced across Australia’s network within a few years. Because so many stations made the switch around the same time, homogenization procedures don’t detect their bias, and assume a natural step up in warming occurred. Worse, the artificial warm bias is transferred to stations that are not automated, reinforcing trends that don’t exist!

“Homogenisation is nonsense, and an open public inquiry into the Bureau’s activities is overdue”, he said.

The Bureau must be audited. Stations should not be homogenized until they are analyzed individually. And the analysis should start with site inspections and a detailed historical account of what is known about each site.

“The Bureau has scant knowledge about many important sites”, Bill said, “and some of what they claim cannot be trusted”.

Temperature is strongly related to local rainfall

Hot years are dry years, and wet years are not hot. It’s tritely obvious, yet kinda profound.  Johnston finds that from half to three quarters of the temperature variation is caused by changes in rainfall. When the land is bone dry, it heats up fast. But when soil moisture is high, the Sun has to evaporate the water first in order to heat the soil. The atmosphere above dry land has lower humidity and will rise and fall in temperature swings that are far larger than the atmosphere above moist landscapes. It varies somewhat with every town, but the relationship is consistent across the continent.

He also found that using rainfall to analyze temperature records reduces variation, while revealing aberrations in the data. What do we make of a town where the effect of rainfall on temperatures has a linear relationship for decades then suddenly changes to a random pattern? Homogenization can produce trends that don’t belong to the site.

New electronic sensors cause an artificial jump

Not only do electronic sensors pick up shorter spikes in temperature, they are also not linear instruments like mercury thermometers are. “AWS don’t measure temperature linearly like thermometers do; which causes them to spike on warms days. This biases the record.

There was also a wave of undocumented site and station changes around the time the Bureau took-over weather observations from the RAAF in the 1950s.  To mention a few; locations affected included Alice Springs, Norfolk Island,  Amberley, Broome, Mt. Gambier, Wagga Wagga and Laverton.

Disturbingly he finds that after many site and equipment changes have been accounted for, and the variability due to rainfall has been ruled out,  no temperature trend remains.

Below Johnston discusses Cowra and Wagga in detail. He observed the weather at Wagga Wagga Research Centre, visited many other sites and discussed issues with the staff. He has worked with climate data, calibrated commercial automatic weather stations and used climate data in many of his peer-reviewed studies.

Bill is pushing for an open public inquiry into the Bureau’s methods; its handling of data and biases in climate records.

Bill Johnston points out that local rainfall is useful for checking temperature data

Ignoring heat-storage in the landscape, which is cyclical; the local energy balance partitions heat loss between evaporation, which is cooling when the local environment is moist; and sensible heat transfer to the atmosphere (advection) during the day and radiation at night, which is warming when the environment is dry. Thus the longer it’s dry, the hotter it gets.

Rainfall is (should-be) linearly related to temperature, especially Tmax, but independent of it.

If the local heat-load changes, forcing a significant base-level shift, the relationship is still linear but is offset by the impact of the change.
If data become grossly disturbed or dislocated from the site (it’s fabricated for example, or implanted from somewhere else), variation around the relationship increases, data become random to each other and statistical linearity is lost. (Rainfall seasonality may also impact on this, but is not considered here.)

So, linearity is expected; and we need a statistic that indicates how good (bad) the relationship is.

Cowra

...

Figure 2. Cowra’s annual average Tmax and Tmin increase with time (dotted line). Tmax weighted by within-year variance to improve precision, increases by 0.4oC/decade (R2adj = 0.332); Tmin by 0.2oC/decade (R2adj = 0.296). Relationships seem highly significant (P< 0.001).Tmax trend includes step-changes in 1979 (+0.63oC; P =0.02) and 1997 (+1.04oC; P < 0.001); and Tmin trend in 1973 (+0.69; P < 0.001) and 1998 (+0.29oC; P= 0.04). Mainly due to missingness, highlighted Tmax data may be faulty.On the right, Tmax declines as rainfall increases: overall, including faulty data by –0.35oC/100 mm rainfall (R2adj = 0.484); excluding faulty data by ‑0.42oC/100mm (R2adj = 0.580) and factored by step-changes (excluding faulty data), by –0.30oC/100mm (R2adj = 0.779). Tmax lines are statistically parallel. Tmin varies randomly with rainfall, so there is no association.

Local rainfall at Cowra explains half of the temperature changes, but when suspect data and step changes are accounted for, rainfall explains over three quarters of the temperature changes:

The main points are that local rainfall naïvely explains 48.4% of overall Tmax variation; 58.0% when four suspect-years are ignored; and  77.9% when data step-changes are also accounted for.

What happened to the warming?

“We shouldn’t think naively of temperature changing in time.” “What we should look at are factors like rainfall and site changes that impact on measurements; account for their effects, then check for trend”, Bill said. 

“Importantly, with step-changes and rainfall accounted-for, there is no residual time-trend.”

Bill explains: “Wagga Wagga and Cowra, get more rain in summer than Rutherglen does”. “Summer rain cools maximum and minimum temperatures together”. “Cloud and fog reduce the numbers of frosty days in wet winters, however”. “Minimum temperatures, which are sensed around dawn each morning, are not as cold as when the sky is clear and the air is dry.”

“Taken overall, summer cooling and winter warming cancel each other-out, which is why Tmin is not so sensitive to annual rainfall”, he said. 

“Rutherglem receives a higher proportion of its annual rainfall in winter in wet years, which results in a much clearer Tmin response”.

 Wagga Wagga

The effect of rain on temperatures in Wagga Wagga

In figure 4, below, more rain in Wagga means cooler maximums (top right) but slightly warmer minimums.

Wagga, Rainfall, temperature, trends, NSW, Australia

Figure 4. Composite analysis of Wagga Wagga Research Centre Tmax and Tmin. Vertical dotted lines indicate metrication in 1972 and the re-location in 1977.  Missing data between 1956 and 1962; in 1968 and 1969; and after 1996 are problematic. However, only a few are outliers in the rainfall domain (right) (red squares). Ignoring them made no difference to trends in the time- or rainfall-domains and had little impact on R2adj.

 

Rutherglen

This graph shows Rutherglen raw data. The step up in 1996 is almost certainly the introduction of the automatic weather station system which resulted in a whopping three quarter of a degree rise in maximum temperature.

The blue line across the top indicates the number of days with data (so there is a big missing slab around 1960).

Bill has compared several brands of commercial automatic weather stations with thermometer data measured in Stevenson screens in the past.

“Upper-range temperatures are mainly affected”, he said. “Data for Rutherglen and elsewhere shows they over-range or ‘spike’ on warm days”. “This affects averages, and shows-up as a step-change”.  

The red squares mark years where temperatures look suspect because they don’t match the rainfall or they have many missing days (say in summer or winter).

 

Rutherglen, Victoria, Temperature, Rainfall

Figure 5. Step changes in Rutherglen’s raw data are indicative of site moves and other data problems. Highlighted data are detected as faulty. Transition to the automatic weather station in 1996 (vertical line) caused an abrupt Tmax increase of 0.75oC relative to previous thermometer data.

Minima are warmed by rain in winter, but cooled in summer

At Rutherglen there is a clear relationship between rainfall and minimum temperature. The record before 1923 is a mixture of Post Office and local data. Some data may also be in-filled between 1924 to 1996. Data from 1997 are from the AWS (and the step is clearly visible).

The faulty data show up as red squares —  they don’t fit with local rainfall.

Rutherglen, Victoria, Temperature, Rainfall, Bureau of Meteorology

Figure 6. Tmin increases with rainfall at Rutherglen and other southern temperate/Mediterranean sites because wet years are cloudy; foggy-winter-days more frequent and rainfall is more winter-dominant than at Wagga Wagga and Cowra.Groups are defined by Tmin step-changes; their group-means are different; regression lines are parallel; some outliers (red squares) are due to missing data others may be faulty. (Median rainfall (566 mm) is indicated by the vertical dotted line.)


Mysterious outliers and the trouble with homogenization

To show how widespread and insidious the problems are Johnston compares two towns in very different and distant locations. Rutherglen is part of the wine-growing region of central Victoria, whereas Ceduna is a coastal spot near the bone dry Nullabor plain of the Great Australian Bight.

See Figure 7 which graph the  temperature and rainfall patterns after the AWS systems were installed at both locations.

Notice two things:

  1. Firstly, the long term average rainfall and temperatures of both locations are plotted as dotted lines — straight across and straight up. This represents the data from the years before the AWS was installed. The data from the electronic  AWS system is forms a trend line that does not pass through the former average ratio (where the averages intersect).
  2. The same years at both places (labelled, 2007, 2009, 2013 and 2014) are well out-of-range relative to the rainfall for those years. At Rutherglen rainfall was near-average in 2013 and 2014; at Ceduna it was above average.

“Its inconceivable that temperatures would be so out-of-range for those years; notably its those years that the Bureau and CSIRO have relentlessly marketed in support of various political goals”, Bill said.

“Ceduna was not specifically chosen as a comparator to Rutherglen. It just happened to be about as far-away, as say, Alice Springs and Bourke, two stations whose data were used to homogenise each other”.  

Why are so many years such outliers, and almost all to the upside? (And the wind whispers… audit the BOM. Audit the BOM…)

Rutherglen, Temperature, Rainfall

Figure 7. Relationship between temperature and rainfall for Rutherglen and as a contrast, Ceduna’s AWS (post 1996). A non-parametric LOcally WEighted Scatterplot Smoothing (LOWESS) curve (smoothing parameter 0.8) fitted with a bootstrapped 95% confidence intervals track curvature. Dotted lines are pre-AWS average Tmax (21.7oC and 23.5oC) and each site’s median rainfall (566 mm and 282 mm). Indicated out-of-range values are suspiciously high relative to the distribution of other data in those years.

Johnston points out that homogenizing data can mean spreading artificial changes into good records:

Like Wagga Wagga airport (72150) and Bathurst Agricultural Institute (63005), Rutherglen is an homogenised ACORN-SAT (Australian Climate Observations Reference Network – Surface Air Temperature) site used to calculate Australia’s warming.

Without accounting for local rainfall, Cowra’s daily data with its faux-trend is used to homogenise Bathurst, Dubbo, Wylong and Canberra. Wagga Wagga Research’s un-trending dataset is used to homogenise Wagga Wagga airport, Cabramurra, Kerang and Rutherglen.

Also without adjusting for rainfall, Wagga Wagga airport and Rutherglen’s ACORN data are used to homogenise other ACORN sites, including some that are quite distant. Much potential exists in the process, for homogenisation to implant problems to other data, especially data not adjusted for rainfall and which are homogenised at daily time-steps.

“It makes no sense that if local rainfall explains most local temperature variation, it is not accounted for somehow in the homogenisation process”, Bill said.

In this graph from Norfolk Island, below, the rainfall increases both maxima and minima, but note the effect of the AWS system.

In the left hand side the step up is obvious. On the right hand side the blue triangles represent the AWS data and its relationship with rainfall. Obviously the AWS is reading artificially high temperatures compared to the rainfall.

Norfolk Island

At Norfolk Island, below, wet years are warmer than dry ones. The electronic AWS readings are also biased-high like at Rutherglen. 

In the left hand side the step up is obvious. On the right hand side the blue triangles represent the AWS data and its relationship with rainfall. Obviously the AWS is reading artificially high temperatures compared to the rainfall.

An important point is that the site was moved to a more exposed location after the Bureau took it over from the Royal New Zealand Air Force in 1948. Together with AWS over-ranging, this results in an artificial Tmin trend. There are many other examples of undocumented site moves that the Bureau seem unaware of and which also cause artificial trends. 


Norfolk Island, Temperature, Rainfall, Bureau of Meteorology

Figure 8. Like Rutherglen, Norfolk Island’s automatic weather station over-reports upper-range temperatures (Tmax +0.17oC, P = 0.07; Tmin + 0.38oC, P <0.001). This causes the instrument to be biased-high relative to the thermometer record, which ended in 1996. There is a Tmin step-change, likely caused by an undocumented site move after the site was taken over by the Bureau from the Royal New Zealand Air Force in 1948 (+0.78oC, <0.01), and a Tmax step-change in 1970 (+0.17oC, P= 0.03); both are undocumented.Grey-circles represent the first data group; red-squares, the intermediate group; blue triangles are AWS data. Lines with unique subscripts (a, b, c) are statistically dissimilar. (Lines a and b are uniquely dissimilar in Tmax; all lines are dissimilar in Tmin.) Data are raw averages and have not been screened for outliers.

Discussion

The dire prognosis from Johnston:

  • It’s hard to find sites where AWS-instruments are not biased-high, like at Rutherglen (Figure 5), Ceduna (Figure 7), and Norfolk Island (Figure 8).
  • In addition to sites already mentioned; AWS-bias occurs in data for Sydney airport, Sydney Observatory, Cape Leeuwin, Hay, Melbourne Regional Office, Geraldton airport (WA), Deniliquin, Mildura, Ballarat airport, Wilsons Promontory, Cape Otway, Bourke, Montague Island, Loxton, Gabo Island and Trangie (ag), to mention some that are analysed.
  • Data for ‘record-hot’ years at many places is highly unusual, and defies explanation (Figure 7).
  • Relationships between local temperature (especially Tmax) and local rainfall are also useful for detecting incongruent data. For instance, Tmax data from 1981 to 1993 at Bridgetown are random with respect to rainfall; thus probably imported from somewhere else. (Some sites, like Cape Otway can be diagnosed using derived metadata, such as counts of high and low extremes (Figure 10).)
...

Figure 10. Cape Otway’s AWS markedly over-reports upper-range temperatures. Data are log10Tmax count ratios of upper to lower extremes. Vertical dashed lines indicate other inhomogeneties. The AWS was installed in 1994 and replaced in 1995. Similar problems are evident across the Bureau’s network.

Conclusions

Temperature data in Australia are not up to the task of tracking climate warming. Most datasets have multiple problems that are not smudged-away by homogenization.

A confounded issue is that AWS-bias infects raw data, homogenized data, and comparisons between networks (ACORN vs. AWAP). Bias is therefore undetected by station comparisons.

There is evidence also that data for manually observed stations (Gunnedah, Moruya PS, and Kerang for instance) are adjusted by the Bureau to agree with the AWS network.

Bias is transferred; it reinforces trends, extremes, and trends in extremes that are due to the instrument, possibly the politics, but demonstrably not the climate.

“Unfortunately, the Minister responsible (Greg Hunt); my local Member (Dr. Andrew Leigh (ALP)) and the Bureau are uninterested in the issues raised here”. Bill concluded.

9.3 out of 10 based on 92 ratings

167 comments to Blockbuster: Are hot days in Australia mostly due to low rainfall, and electronic thermometers — not CO2?

  • #
    Roger

    Absolutely correct that electronic thermometers record transient temperature that is not captured by traditional thermometers. The UK’s record July temperature this year alongside the runways at Heathrow Airport – by around 0.1 deg C – and widely PR’d by the Met Office was seperately checked and analysed in detail in the Met Office records.

    That found that there was a temperature spike of 0.9 deg which lasted just 2 minutes before dropping back to the previous hour’s temperatures. The met Office records temperatures at 2 minute intervals. Further research into this showed a wind direction change for just a few minutes during this heat spike and the found that coincidentally a Boeing Dreamliner was maonoevering on the taxiway adjacent to the thermometer.

    Given how determinedly warmist the Met office is it is not surprising that they did not find it all curious that the temperature rose by 0.9 deg C for a two minute period – and equally so that they would, with not the least scientific embarrassment claim this to be a New Record and Proof of ‘Global warming’.

    Any true scientists would have been highly sceptical of a jump in temp of 0.9 deg C lasting just 2 minutes – but it seems that Met Office climate ‘scientists’ don’t fit into that category.

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    • #
      me@home

      OMG It IS worse that we thought. I knew about the steps but not the 2 minute periods. No lay person hearing the weather report would guess that a so-called record high temp was due entirely to a heat spike from a momentary wind change alongside an airport runway. What else could the MET due to fabricate such “records”?

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      • #
        me@home

        A further thought is that the system of taking a single unrepresentative temp. reading of one 2 min. period as the max. for the day may technically be correct but is so totally misleading that one could be forgiven for thinking that it must be deliberate.

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        • #
          Don

          A two minute sample would *not* be correct if that sample is likely to be wrong. Min() or Max() of raw data with known bad samples is a mistake. The data would need to be filtered to have “correct” metric.

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    • #
      JohnM

      Of course an electronic response is faster than a response in a column of mercury. The big question is how many AWSs are subject to fleeting bursts of warm air.

      Also in the bigger scheme of things you have to remember that only two temperatures matter each day – the minimum and the maximum.

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      • #
        Ian George

        So true, John.
        An example of this was on the 18th Jan, 2013 Sydney Obs recorded its highest temp on record at 45.8C. This happened at 2:53pm.
        According to the AWS data, the temp was 44.9C at 2:49pm and then 44.8C at 2:59pm.
        So the temp rose 0.9C in four minutes and dropped 1.0C in six minutes – but the graph for that day showed the graph-line just sneaking over the 45C mark.
        The old record of 45.3C was set in 1939. I wondered what it would have been had it not been a mercury-in-glass thermometer.

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        • #
          AndyG55

          Actually, I viewed the “summary’ next day (wish I’d taken a screen capture 🙁 )

          and it stated a maximum of 45.3C

          I even emailed BOM asking where the extra 0.5C came from, and , of course, got no answer.

          Let’s not forget that in 1939, a lot of Western Sydney was farmland, compare that to now.

          The really hot weather in Sydney comes from the west.

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          • #
            AndyG55

            Still.. a “maybe, but probably not” rise in max temp of 0.5C in, what, 74 years!!!

            Gees, is anyone panicking ?

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          • #
            Ian George

            Andy
            I have screen captures of what happened on that day but I can’t seem to transport them on to this.

            30

          • #
            ralph ellis

            >>Actually, I viewed the “summary’ next
            >>day (wish I’d taken a screen cap.

            Have you tried the Wayback machine, to get the old data?

            R

            11

      • #
        Graeme No.3

        JohnM;

        An average of the daily Max and Min. however accurately measured is a very poor way of measuring heat.

        Consider a day that started at 22℃ and climbed to 28℃ and dropping to 25℃ overnight v a day starting at 15℃ and climbing to 25℃ by 3pm then rising in the next hour to 35℃ at 4 pm and then dropping rapidly to 10℃ by 7 p.m. Both are an average of 25℃ but which would you rather live in?

        50

    • #
      Ted O'Brien.

      2 minute temperatures. Not scientific, but when exposed to the wind on a hot windy rural Australian day, as when riding a horse or motor bike, at times you may get hit with a gust which seems much hotter than the prevailing wind.

      This is only feel, not instrumental, but it made and makes me suspect that the atmosphere is far from homogenous, even over small areas.

      Another phenomenon that I observed just once, where I lived all my life some 150 to 200 km west of the NSW seaboard, on most hot summer days the “sea breeze” reached us inland in the afternoon. Hot nights were rare.

      This wind change was visible as it approached, carrying coastal smog. One day when there was a big bushfire about 60 km to the east, when that wind change came, the first breath of it carried the smell of the smoke. Go figure.

      I think the westerly air must have moved up instead of pushed backwards. But that still doesn’t put the smoke at the lead.

      50

    • #
      Russell

      Off Topic – but I assume you have seen this: https://www.youtube.com/watch?v=SyUDGfCNC-k

      20

  • #
    Peter Azlac

    Klaus Hager carried out a study comparing MMTS and Glass thermometers side by side for a period of 8.5 years and found that the MMTS gave a mean difference that was 0.93C warmer.
    “Differences in the daily maximum temperatures from the Pt 100 compared to glass thermometers for 3124 days (ca. 8.5 years) conducted at the GeiInfoAdvisory Office of Fliegerhorst Lechfeld (from 4) – mean difference 0.93°C. “
    http://notrickszone.com/2015/01/13/weather-instrumentation-debacle-analysis-shows-0-9c-of-germanys-warming-may-be-due-to-transition-to-electronic-measurement/
    Yet on the basis of one limited test comparing an MMTS and Glass Thermometer the “experts” in charge of manipulating the temperature series through homogenization and kriging claim that they give cooler values. As Zeke Hausfather stated
    “Back in the 1940s virtually all the stations used liquid-in-glass thermometers, which read about 0.6 degrees warmer in max temperatures (and about 0.2 degrees colder in min temperatures) than the new MMTS instruments introduced in the 1980s. This means that actual max temperatures (as measured by MMTS instruments) would have been ~0.6 degrees colder, and contribute part of the reason for adjusting past temps downwards.”
    Or did he mean this
    All of these changes introduce (non-random) systemic biases into the network. For example, MMTS sensors tend to read maximum daily temperatures about 0.5 C colder than LiG thermometers at the same location.
    http://judithcurry.com/2014/07/07/understanding-adjustments-to-temperature-data/
    Also, it is not just rainfall that must be taken into account but the effects of irrigation that are certainly a factor at Rutherglen and other stations in the Snowy Mountain irrigation scheme.
    http://variable-variability.blogspot.com/2015/04/irrigation-paint-cooling-bias.html

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    • #
      el gordo

      Excellent work, Peter.

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    • #
      KinkyKeith

      This is real science.

      From the first paragraph there is strong evidence to suggest that old technology temperature measurements (lig) should be increased by 0.93.

      This is the reverse of current homogenisation.

      May need to standardise the adjustment depending on local temps.

      This MUST be the best way of getting at the truth; the results are not contestable.

      KK

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      • #
        Craig Thomas

        “This is the reverse of current homogenisation.”

        No it isn’t.
        As Anthony Watts proved in the USA – homogenisation introduces a cooling bias.
        The net effect of BoM’s work here is also very slightly on the cooling side.
        (This is why people who hate BoM so much don’t look at the overall results, but instead cherrypick a handful of stations whose records suit their arguments.)

        And before you go adding 0.93 to all the old temperatures – maybe we can see some actual published science to support this university lecturer’s tall tales???
        Being a sceptic myself, I’m not going to believe him unless he provides proof.

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        • #
          Bill Johnston

          Good morning skeptical Craig.

          Why don’t you grab some data and analyse it for yourself?

          Australia’s ‘overall temperature’ is the sum of its parts. If its parts are largely faulty and their history is poorly known, then homogenisation of any kind is no help.

          The Bureau said “There have been no documented site moves during the site’s history.” They had access to Simon Torok’s thesis. Torok said there were changes and moves at the site; so did the data.

          The site has an interesting history. The first weather records were (probably) reported from the Rutherglen Post/telegraph Office. A viticulture college preceded the Agricultural Institute, which according to newspaper reports, was established in about 1930 after the last viticulture student graduated. (Viticulture started off with a bang, but then dwindled to having no students.)Viticulture ran a met-lawn, but no one seems to know where it was.

          When it became an agricultural station (one of 4 I believe), they took-over a patchy record; which was later compiled with the PO record to form what we now know as ‘Rutherglen Research”.

          Why this is important is that the first part of the record (the compiled to 1924) is warmer in Tmin, which of-course sets-off a bogus trend. (You understand trend don’t you Craig?)

          Compilation did not affect Tmax at that time. However, dodgy (inconsistent) data came into the Tmax record from 1941 to 1959. It would be interesting to check original data for that period, but they are not available. Missing data was an issue, also possibly poor data or site hygiene, but its not possible to tell from staring at the data alone. The Bureau are clueless about data issues, and in fact they admit to having destroyed large numbers of paper files, without electronically archiving them. It is also possible that data are infilled from somewhere else, Corowa or Chiltern for instance.

          These possibilities make the record unreliable. (You know about the importance of reliability, don’t you Craig?)

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        • #
          Ernest Bush

          I am skeptical of your claim that Anthony Watts proved that homogenisation introduces a cooling bias. As I recall, most of the contributors at that site, including Anthony, have shown that when data from the outlying stations is made up or not used, then the UHI effect automatically causes the temperatures to read warmer. NASA seems to be using fewer and fewer stations over time even where good data is available. It seems that the remaining stations are purposely located in urban centers. The net result is a warmer temperature average from GISS and other land-based records.

          230

        • #
          Craig Thomas

          It’s good to be sceptical.
          https://pielkeclimatesci.files.wordpress.com/2011/07/r-367.pdf

          Watts was so miffed about this work proving him wrong about station exposure that he went double-or-nothing on the BEST study.
          Sadly for Watts, BEST confirmed the exact same thing, as we all know.

          This is why Watts has quietly suppressed the results of the work at surfacestations.org.

          325

          • #
            cohenite

            From the Fall et al paper co-authored by Watts:

            Comparison of observed temperatures with NARR shows that the most poorly sited stations are warmer compared to NARR than are other stations, and a major portion of this bias is associated with the siting classification rather than the geographical distribution of stations. According to the best‐sited stations, the diurnal temperature range in the lower 48 states has no century‐scale trend.

            Apart from showing warming the analysis also showed no DTR decline; a decline in DTR is a prediction of alarmism.

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        • #
          Tim Hammond

          So cooling the past and warming the present is introducing a cooling bias? So what? If I make the past cooler and the present warmer, I make my Alarmist hypothesis look more convincing.

          That’s the point, fake sceptic.

          100

    • #
      Craig Thomas

      Interesting, although I notice all your links are links to blogs.
      Does this information about Klaus Hager have a reputable source you can refer us to?
      Presumably this valuable research has been published?

      240

      • #

        Easily found by following links from the blog. (PDF)

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        • #
          Rereke Whakaaro

          Good to see that you are still acting as Craig Thomas’s secretary, Bernd. 😉

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        • #
          Craig Thomas

          As suspected – not a science paper, but an unpublished work of (presumed) fiction, written by an unqualified nobody who is prone to maknig cranky statements and copied out of a virtually unknown journal called “Berlin WeatherMaps”.

          And, as usual, that’s the best you’ve got. How pathetic.

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          • #
            Rereke Whakaaro

            Are you writing a biography of Albert Einstein, by any chance, Craig?

            I only ask, because your last comment could equally apply to Einstein’s early work.

            You have heard of Einstein, I presume?

            190

          • #

            “Craig Thomas” wrote:

            As suspected – not a science paper, but an unpublished work of (presumed) fiction

            You’re obviously a denier: It was published in a journal, not copied from it.

            You seem to use your ignorance of journals to deny their existence.

            And you deny who’s qualified.

            Your denial of the fundamental physics of instrumentation indicates that you aren’t qualified in the subject; and if you were “qualified”, then you’re undeniably incompetent.

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      • #
        el gordo

        ‘Being a sceptic myself…’

        ** chuckle **

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      • #
        James Bradley

        Craig,

        The BOM has been homoginising historical temps down when the temps shoud be adjusted up – but then the warming trend would disappear – goodness gracious me.

        262

        • #
          Craig Thomas

          James, you’ve unsceptically swallowed a fairy-tale.

          The work the BoM does is professional, it is documented in the academic literature, it is tested and checked by other organisations, and it so far has proven sound.

          And as I said before – the net effect of homogenisation has been shown to introduce a cooling bias.
          The BoM has shown that the raw data (if you were silly enough to think analysing raw data was sensible) displays a steeper temperature increase than the homogenised data does.

          332

          • #
            el gordo

            ‘The BoM has shown that the raw data (if you were silly enough to think analysing raw data was sensible) displays a steeper temperature increase than the homogenised data does.’

            Do you have a graph to illustrate your argument?

            182

          • #
            Ted O'Brien.

            Raw data are THE data.

            All the rest are statistics.

            191

          • #
          • #
            Rereke Whakaaro

            Analysis of what Craig wrote:

            The work the BoM does is professional, …

            They are paid to do, whatever it is that they do.

            … it is documented in the academic literature

            People who work in the cloistered, rarified atmosphere of universities, occasionally refer to it in passing.

            … it is tested and checked by other organisations

            On a quid-pro-quo basis – “I will review your paper, if you will review mine”. It happens all the time in academia, I know, from first hand experience. A factoid, that I perceive that Craig avoided.

            … and it so far has proven sound

            Yes, well it would, wouldn’t it.

            Perhaps Craig can enlighten us by excplaining why I can write to a Learned Society specialising in say, Aerodynamic Research, asking for the results of some experiment, and get it by return of mail. Of course, I have to pay a fee, which I don’t mind, because they have to recoop costs. But if I write to any organisation that is a peer of the BOM and ask for a copy of the raw data, and the rationale for any adjustments to that data, it is refused out of hand?

            I am sure that there is a valid explaination. If there were not, what the BOM, and its sister organisations, do, would not be science, would it?

            181

          • #

            News for you Craig, the BOM admitted this year that no one can replicate their work, and they will not help anyone do it either.
            http://joannenova.com.au/2015/06/if-it-cant-be-replicated-it-isnt-science-bom-admits-temperature-adjustments-are-secret/

            212

            • #
              Craigthomas

              As usual, you misrepresent what other people have said.
              What the BoM said, essentially, is that people like you are incapable of providing any kind of analysis of their observations: you just don’t have the skills.

              14

              • #

                As usual Craig, I quote the BOM forum word for word exactly to back up what I said (follow the link).

                You provide nothing but bluster. Read what they said — they would not provide the information required for anyone outside the BOM because it was too complex and required too much “operator intervention”, and was a “supervised process”. Their decisions cannot be written down and published even in a peer reviewed journal for fellow experts. It is not possible to replicate their methods.

                If it can’t be replicated, it isn’t science.

                40

              • #
                Bill

                Let me spell it out for you Craig: legitimate science is defined as REPUTABLE, REPEATABLE, and VERIFIABLE. Your pet theories meet none of the criteria.

                Another hint for you, even other warmists have gone on record to state the Manns “work” is garbage.

                30

        • #
          James Bradley

          Craig,

          Rubbish.

          154

      • #
        Egor TheOne

        “Interesting” ……You don’t have any links at all , Along with clues !

        51

  • #
    Bengt Abelsson

    Can “The Pause” be explained by assuming that the shift in thermometer types is slowing? Or maybe completed around 1998?

    132

    • #
      RB

      Its sea-surface temperatures wouldn’t be as affected.

      I strongly suspect that the pause in thermometer temperatures would not be there if there weren’t satellite measurements.

      170

    • #
      Craig Thomas

      Where’s your scepticism, Bengt? You don’t actually believe this unproven story do you?

      437

      • #
        James Bradley

        Craig,

        A true skeptic would say that it needs further investigation.

        152

      • #
        Rereke Whakaaro

        Since when, did belief have anything to do with science.

        Bengt’s question was perfectly valid, and it now up to the rest of us to demonstrate that his question was without merit, from a scientific perspective, if we can. You go first Craig, since you asked the question …

        171

      • #
        RB

        Written badly,it might have been but didn’t I point out a flaw in Bengt’s assumption?

        As for Bill Johnson’s work, I have yet to go through it thoroughly in order to be convinced. You seem to have called it a fairy story (no hyphen unless both words are the adjective) within minutes of reading the title of this blog because you believe its heresy.

        61

  • #
    Manfred

    “Hot July brings cooling showers, Apricots and gillyflowers.”
    Sara Coleridge, 1802 – 1852 (daughter of Samuel Taylor)

    Acknowledgement to Karen and Mike Garofalo

    “Unfortunately, the Minister responsible (Greg Hunt); my local Member (Dr. Andrew Leigh (ALP)) and the Bureau are uninterested in the issues raised here”.

    Negligence at a helm bereft of duty in due diligence. It will return to haunt them all one of these days.

    270

    • #
      KinkyKeith

      Manfred, I think that this is one of those things that the general public could understand very easily.

      IF it could be publicised in the mainstream media it would certainly embarrass those “at the helm”.

      152

      • #
        Craig Thomas

        The public is perfectly satisfied with our BoM – one of the world’s best scientific organisations.
        You and this Johnston joker are waaaaay out on the fringe with this.

        352

        • #
          Yonniestone

          The centre left is considered waaaaay out on the fringe in your comprehension CT.

          As part of your deprogramming therapy remember, open debate is healthy and the freedom to do so is not illegal, cheers.

          291

        • #
          macha

          Where is your proof in this clsim. I certainly aint satsfied with BOM integrity and transpatency.

          361

        • #
          KinkyKeith

          Sadly, like the CSIRO, FORMERLY, one of the “world’s best scientific organisations”.

          Reminds me of the term Carbon Capture and Storage (CCS). What a joke.

          Now we have both these organisations “captured” and “sequestered ” from their original tasks (CSOT).

          This post shows dramatically how the BoM has not only changed the numbers BUT has changed them in the wrong direction.

          Now that’s what I call DEVIOUS but I would never call it science.

          KK

          332

          • #
            Yonniestone

            Capturing and sequestering carbon has been utilised by many similar thinking organisations in history, it used to be called genocide.

            222

          • #
            AndyG55

            The very best place to store CO2 is in the atmosphere or in beverage bottles. 🙂

            Those are the two of the most useful places to put it.

            141

            • #
              Sceptical Sam

              ” in beverage bottles. 🙂 ”

              Exactly.

              And it seems to me that Craig, where-ever he lives, confirms that.

              It seems he got back to his desk (in Canberra?) after a long lunch and decided he should be seen by his boss to be hard at work on his computer.

              While we can see the product of his fantasy, his boss can’t.

              And that tells us all we need to know.

              51

        • #
          TdeF

          So now you speak for the public? No one else here speaks for anyone but themselves, but you speak for the public, a rare privilege in a skeptic. So the usual stuff, established science, peer review. In your perfect world scientists do not lie. Especially famous scientists like maths ignorant Nobel Peace laureate Al Gore or Roo boy Professor Tim Flannery or the entire Climate Council of Australia, not one a meteorologist. The rest sadly are highly politicized organizations including the IPCC which is a UN appointed committee of politicians, not scientists.

          331

        • #
          Dariusz

          I deal with csiro with my projects (I am a geo working in private industry) and what I found from personal experience that they are slow, inefficient with capacity to integrate of a 5th grade scientists. Would never employ them in my company.
          As a member of public I consider csiro waaaaay on the fringe of best practice.

          341

        • #
          Manfred

          Ohhh pllleeaseee CT….
          Before you start throwing about accolades you’d be wise to define what you mean when you merely imply by courtesy of using that vague word, ‘best’?

          111

        • #
          James Bradley

          Craig,

          Please, why did the BOM have the audit shut down with the help of collaborative members of the current government.

          201

          • #
            Craig Thomas

            Because it was pointless to duplicate (poorly) audit work that is already being done (properly).

            333

            • #
              AndyG55

              Your boyfriend work there or something, Craig?

              Never seen such a rabid defence of something that should be audited every few years as a matter of course.

              235

            • #
              James Bradley

              Craig,

              Then why fight the audit then leave the explanations to such as you?

              222

              • #
                Rereke Whakaaro

                It is Craig, who appears to be Loopy. His word, not mine.

                112

              • #
                Yonniestone

                Because Craig is doing Gaia’s work but starting to think for himself, a first step towards critical thinking, the reprogramming is coming along nicely, good for you Craig.

                62

        • #
          Bulldust

          Trollbait notwithstanding … why should the general public’s opinion of BoM carry any scientific merit at all? Their mysterious temperature tampering which they refuse to detail is unscientific behaviour. They must be channeling Prof Jones… why would they share their data and adjustments if sceeptics are only going to find fault, eh?

          If there’s nothing to hide, then there is no reason to hide. End of story. It doesn’t necessary follow that hiding implies there’s something fishy going on, but perception says otherwise. The perception of corruption is just as bad as corruption. Anyone who works in government knows this.

          Never mind that the whole concept of deriving an average global temperature anomoly from sporadically placed thermometer stations is complete garbage, let alone the statistical manipulation of said readings. Only someone with an agenda would profess the derived temperature statistics have any scientific validty at all. Humans are exceptionally “gifted” at finding patterns where none exist, especially when there are billion-dollar incentives involved.

          281

        • #
          Rereke Whakaaro

          I actually agree with Craig, on this. The BOM is the best Weather Bureau that Australia currently has. They know their isobars.

          But when it comes to climate … not so good. But I guess you can’t be great at everything.

          191

    • #
      SPOTTY

      I do live in Greg Hunt’s electorate and have already informed that his actions in cancelling the investigation into the methodology of the BOM and his refusal to attend the meeting of Jennifer Morahassy and Ian Plimer with warmist scientists (arranged by a member of his own party) has cost him the votes of myself and my wife.

      Both of whom have voted Liberal for over 50 years.

      201

  • #
    Ursus Augustus

    This has that ring of truth about it. The reasoning is common sense and simple to follow. All the more likely to be scoffed at by ‘experts’ and their bum sniffers in the msm.

    When it comes to common sense in ‘climate science’, the experts have no clothes, not even undies.

    Just in time for Paris as well!

    Thank you Bill Johnson.

    200

    • #
      Rereke Whakaaro

      … bum sniffers in the msm.

      I like that. Very droll. It gives a whole new meaning to the phrase, “news hounds”.

      130

  • #
    handjive

    If the 97% BoM can get away with this 100% failure to the Senate Estimates Hearing …
    . . .
    ABC, 13 May 2015:

    A major El Nino event, which is likely to lead to prolonged drier, hotter conditions across much of eastern Australia, has been officially declared by the Bureau of Meteorology (BoM)

    The Bureau said it had a “near miss” with declaring an event last year, with some indications showing sea surface temperatures were at El Nino levels.
    ~ ~ ~
    ABC, 6 Oct, 2015: ‘Godzilla El Nino’ intensifying: Drought, heatwaves and heightened bushfire risk expected this summer
    ~ ~ ~
    ABC, 19 Oct 2015:

    Appearing at a Senate Estimates hearing in Canberra, bureau director Dr Rob Vertessy said that while the current El Nino had not yet reached the peak of record-setting events in 1982 and 1997, “we forecast it to get there eventually around Christmas, and the phenomenon could persist well into the autumn”.

    The changes are now starting to reinforce the El Nino conditions and stop a feed of moist air from the Indian Ocean into the continent, Dr Vertessy said.
    ~ ~ ~

    ABC, 12 Nov, 2015: Big rain events don’t mean El Nino’s over just yet: Weather Bureau

    Heavy rain has ruined some grain crops and held up harvest in parts of South Australia, Victoria, NSW and Queensland.

    “We’re not too far off the peak of El Nino [now]; we also know that the Indian Ocean dipole will break down around November, early December, so that extra drying influence will start to ease,” Dr Watkins said.

    What we don’t know, is what’s going to happen with that really warm Indian Ocean.

    It’s the warmest we’ve ever seen, so it’s hard to compare it to anything.

    “But it doesn’t really matter: it’s a significant event, in the top three …” said the Bureau’s manager of climate prediction, Dr Andrew Watkins.
    . . .
    “It doesn’t really matter?”

    Tell that to the farmers that de-stocked.
    Tell that to the farmers who’s grain crop has been ruined.
    Tell that to another Senate Estimates Hearing when you are asking for more money from hapless Australian Tax payers.

    No chance of accountability, as PM Talkbull showed when he closed down an inquiry into BoM data adjustment methods.

    180

    • #
      Craig Thomas

      No chance of accountability, as PM Talkbull showed when he closed down an inquiry into BoM data adjustment methods.

      Of course they are accountable – their methods are checked and tested internationally.
      We certainly don’t need an “inquiry” into our BoM being conducted by unqualified [snip] with a political axe to grind.

      [So all you have is an ad hom? If only you could find some evidence or an argument eh?] Jo

      454

      • #
        Dennis

        You are wrong. There has already been an internal investigation at the BoM after the minister responsible was advised that media briefings from the climate change division/department did not match BoM historical records data. The investigation resulted in an admission that there have been errors and omissions and that procedures were being put in place to ensure it does not continue.

        That was the basis for the following call for due diligence to be undertaken at BoM.

        Unfortunately climate change specific personnel in many organisations have been guilty of [snip – wait for the courts to decide that… Jo]

        121

      • #
        handjive

        Hi Craig.
        Kudos for your concerned response.
        Can you provide any evidence of these international checks & tests?

        Thanks in advance.

        211

        • #
          Ted O'Brien.

          “their methods are checked and tested internationally.”

          Pal review?

          131

          • #
            AndyG55

            The base methodology is checked, and proven to create warming trends in every data set it is applied to.

            AND we don’t know if they are applying that methodology correctly, anyway.

            We only have their word for it, and with billions and billions of dollars resting on it…

            THAT IS JUST NOT GOOD ENOUGH !!

            112

      • #
        James Bradley

        craig,

        A skeptic would say otherwise.

        82

      • #
        Rereke Whakaaro

        We certainly don’t need an “inquiry” into our BoM being conducted by unqualified [snip] with a political axe to grind.

        And for those of us who have managed to extricate ourselves from the misfortune of treading the corridors of power, the translation of the polikspek in that statement (minus the snip – you naughty boy) is: “inquiry”, people poking into our affairs; “unqualified”, people who don’t know our arcane methods; “political axe to grind”, people like me, who point out the inanity if their pronouncements, just for the fun of it.

        But Craig tries hard. I am sure he will improve, over time.

        181

        • #
          Graeme No.3

          “I am sure he will improve, over time.”

          You are a real optimist.
          I just hope young Craig is an opsimath.

          61

        • #
          llew jones

          Though CO2 is a vital gas to all life on Earth and its growing atmospheric concentration is contributing to the greening of the planet it is a great pity that that extra CO2 does not seem to have the capacity to improve human brain function e.g. Craig Thomas.

          He of course is a typical AGW alarmist, all of whom have little to no understanding of the science they imagine supports their attacks on the energy sources that are crucial to the technically advanced societies that they along with the more rational of us so richly in every way benefit from. If they were informed enough and had the intelligence to apply that information they would soon leave the AGW religion. That religion, on the evidence here and elsewhere obviously attracts uninformed dimwits.

          81

    • #

      Too much cloud over the oceans to drive a big el Niño?

      Perhaps we’ll never know if nobody bothered to measure it using satellites.

      140

    • #
      pat

      handjive –

      ABC’s Anna Vidot wrote the 19 Oct piece, yet she doesn’t challenge BoM over their failed predictions when she writes the 12 Nov piece!

      how do they get away with it?

      151

  • #

    Back when the Australian standards for the Stevenson screen were being decided (1884-1887ish)some of the meteorologists involved in the process wanted to make them out of zinc instead of wood.
    Wood has a large specific heat compared to air but zinc has a far lower specific heat than air.The Stevenson boxes would have been a lot more accurate during transitions if they had been Zinc.
    Air 1005 J/kg/Degree.
    Zinc 388 J/kg/Degree.
    Wood 1700 J/kg/Degree.
    http://www.engineeringtoolbox.com/specific-heat-capacity-d_391.html
    Sadly they would have feared that the morning observers would have found the expensive thermometer on the ground because someone had made off with the box.
    I wonder what the old record highs would have been if the Standard Stevenson screen had been a rapidly sensitive device instead of a big wooden thermal lag. As Roger showed in post no 1 the greater sensitivity to rapid change of the modern AWS allows the cause of that spike to be seen.
    http://trove.nla.gov.au/ndp/del/article/52067352
    http://trove.nla.gov.au/ndp/del/article/65743411
    Bill raises questions that should be the talk of the town in Paris however I think the AWS is more linear with change of air temperature than the dodgy old wooden Stevenson. None the less the records cannot be homogenised together.

    191

    • #

      Zinc’s density is higher than that of wood. And zinc, by itself isn’t a good structural material. Costs would have been a significant factor as a higher cost would have meant fewer stations for the same budget, reducing coverage.

      As Hager noted, the average temperatures were higher when using electronic (Pt 100) sensors with forced convection, than in a Stevenson (and similar) shelter with internal, natural convection. Anybody who measures temperature professionally in engineering understands that forced convection provides a quicker response to temperature changes and a smaller sensor (thermal) mass; characteristic of electronic sensors; even more so. The Lechfeld situation also provides another hint that not the same thing is being measured by electronic systems as with those in traditional shelters; the height of the sensor: electronic sensors are at 2 metres above the surface whereas the older shelter’s instruments are at a comfortable working height of just over 1 metre.

      Different quantities are being measured. In the shelter; it’s the height of a column of liquid in a glass tube and in the electronic sensor, it’s the ability of an electronic element to lose heat to the surrounding air.

      Also described by Hager is the way that minima, maxima and average temperatures are established; they are vastly different for the two types of instrument.

      There is no way of “homogenising” the differences between the two types of data sets without a great deal more detail being used from the electronic systems to compensate for sensor response times and time of reading. i.e. one uses the faster-response data, adjusted for comparable thermal inertia in the instruments as well as comparable times of observation. Which still leaves a gaping chasm of different instrument shelters at different heights for which there are insufficient physical (especially thermal) comparisons to permit adjustments based on measurable, physical properties. e.g. Doubling the sensor height can make a significant difference to the wind speeds at the sensor; depending on surface profile. Different air is being measured at a different condition.

      In attempting to make one data set out of several, one destroys all the raw data. All that tends to remain are artifacts of the subjective corruptions of data referred to as “homogenising”.

      180

    • #
      ROM

      With the faster reacting electronic sensors in the Stevenson screens the quite common thermal created temperature spikes which last for a minute or even two minutes would be registered .
      Personal observations acquired over some 50 years of gliding at Horsham in west Vic following.

      The Met Station at Horsham Airfield, note that Airfield bit, is located near the junctions of the two runways.

      The East / West runway was built in the mid 1960’s. It is a sealed runway of some 30 metres wide and 1300 metres long so is one hell of a big heat sink / source.

      Never stated but it was a final inner ring air defence strip for the jet fighters of the 1960’s when Indonesia under Soeharto had Confrontasi [ including a low level war against the British Sarawak in Borneo] with the west and had Russian built bombers that could make the flight from Indonesia to Australia’s SE capital cities.

      The North / South runway was a dirt, supposedly grassed strip which was sealed in about 2010 or thereabouts. It is a now a 22 metre wide seal and is another big heat sink / source.
      Prevailing winds are from the North East around through the West and into the South.

      The station which was established on the airfield in around 1990 or soon after, is located to the south of the main E/ W runway and west of the N/S runway.
      It is located about a hundred metres from the intersections of the two runways so it is immediately down wind in an arc of around 200 degrees from the two very significant heat sources from the NE around through to the SW.

      Google Earth and you will see the layout.

      On hot days out on those sealed runways it gets bloody hot as the heat is absorbed by the black top seal and we spent as little time as possible out on that seal when getting ready to launch our gliders especially when it gets 38C or more as possible as it is a couple or more degrees hotter on the seal than on the grass immediately alongside of the black top seal.

      Of course we were out there with the gliders on those hot days to catch the thermals which usually but not always are damn good on hot days.

      Thermals of course are columns of warmer air, maybe a degree or even two or three degrees warmer than the surrounding air mass and are a couple of hundred of metres across at ground level to a kilometer or so across at height,
      The air mass in the thermal expands due to the higher temperatures of the air in the thermal and having expanded that little bit, is like a hot air balloon, lighter than the surrounding air mass and therefore it tries to rise.

      It is a process that entraps and draws more air into the bottom of the rising thermal, warming it up as it passes across the heat source and so you have your rising air column, your thermal which on days when the moisture content and lapse rates and dew points are in line, creates those puffy cumulous clouds you see high in the sky.

      ALL clouds regardless other than the stratospheric noctilucent clouds, are formed by rising air masses and the moisture condensing out of those rising air masses when the warm moist air hits the cold air aloft, a not dissimilar process to your moist breath creating a personal fog when you breathe out on a very frosty morning.

      Those thermal air masses as they drift downwind and in our case, across the runways at our airfield, are often a couple of degrees warmer than the surrounding air masses.
      The temperature increase on a very hot day can actually be felt when in the path of the thermal as well as the wind increases a little as the air flows into the bottom of the downwind drifting thermal.
      Sometimes a willy willy is generated off the hot sealed runway in that thermal air mass as well.
      Then after a couple of minutes the wind dies down as the thermal air mass continues to drift down wind and you can feel the drop in temperature of a degree or so if you take careful note.

      Again in our case and I suspect at many airfields that are home to a lot of BOM’s stations, those same thermals will often drift across our BOM station after passing over the hot sealed runway and no doubt create quite a nice spike in temperature on the fast reacting electronic sensors.

      We can actually see these temperature spikes whilst they are happening when we watch the read outs from the BOM station in the local Aeroclub rooms on the BOM’s local station computer readouts.

      And then you have a nice spike which as a BOM climate person , you don’t tell the public it was only a short minute or less spike, that you can claim as having set another or even a new high temperature record.

      Glider pilots, farmers, outdoors folk just shrug and just get on with life.

      The greens and troglodytes of the urban caves and caverns from which they rarely emerge into the real world outside, wet their panties at the horror of it all and blame all that coal for the temperature ills of the world whilst they head across to the aircon to wind the power consuming air con temps down another notch.

      And the ABC and numerous proffessors of arcane disciplines and the BOM spokespersons pontificate at great length and from great ignorance on the hell that the world is about to enter sometime yesterday “unless we do something.”

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      • #
        JohnOh

        While in an email exchange with one of the BOM techs who look after recording equipment at airports, he let fly that the reason for equipment failure at airports was due to it being an area where lightning hit these structures as the were the highest in the area, measuring some five meters of the ground.
        That explains why in a the last four years why rain has gone missing locally and why low temperature reading have failed to show up in winter.
        Accuracy appears to be something you wish for, where reality is some thing you get….and it all adds up to less rain and higher temperature.
        Seems like they are actually starting to admit their temperature and rainfall figures are completely inaccurate.
        We are down 60 points of rain and previous years to this lost 30 mils per year at times.
        But missing data isnt even recorded, not is it stated that the equipment failed on a day. Anywhere.
        PS why do they put weather stations near airports if lightning is so prevalent to failed equipment?

        00

  • #
    Craig Thomas

    I don’t see why we would listen to what Johnston has to say, considering the misleading nonsense he got caught out trying to spread about Rutherglen.

    And he’s still not making sense, “homogenisation is nonsense”……”the data is faulty”. Der.

    449

    • #
      AndyG55

      Yet you think people are going to pay the least bit of notice to anything a KNOWN CONMAN AND LIAR like you says ?

      Bizarre.

      242

    • #

      Why do you ignore the differences in measurement techniques?

      Why do refuse to try to understand that different things are being measured and that “temperature” incompletely describes the energy state of the air?

      Electronic and liquid-in-glass thermometers measure different physical quantities. They have vastly different thermal mass and the manner of recording “temperatures” is substantially different.

      161

    • #
      TerryG

      Who’s going to be sacked for making-up global warming at Rutherglen?
      August 27, 2014.

      Rutherglen, a small town in a wine-growing region of NE Victoria, temperatures have been measured at a research station since November 1912. There are no documented site moves. An automatic weather station was installed on 29th January 1998.

      Temperatures measured at the weather station form part of the ACORN-SAT network, so the information from this station is checked for discontinuities before inclusion into the official record that is used to calculate temperature trends for Victoria, Australia, and also the United Nation’s Intergovernmental Panel on Climate Change (IPCC).

      The unhomogenized/raw mean annual minimum temperature trend for Rutherglen for the 100-year period from January 1913 through to December 2013 shows a slight cooling trend of 0.35 degree C per 100 years. After homogenization there is a warming trend of 1.73 degree C per 100 years. This warming trend is essentially achieved by progressively dropping down the temperatures from 1973 back through to 1913. For the year of 1913 the difference between the raw temperature and the ACORN-SAT temperature is a massive 1.8 degree C.

      There is absolutely no justification for doing this.

      This cooling of past temperatures is a new trick* that the mainstream climate science community has endorsed over recent years to ensure next year is always hotter than last year – at least for Australia.

      There is an extensive literature that provides reasons why homogenization is sometimes necessary, for example, to create continuous records when weather stations move locations within the same general area i.e. from a post office to an airport. But the way the method has been implemented at Rutherglen is not consistent with the original principle which is that changes should only be made to correct for non-climatic factors.

      In the case of Rutherglen the Bureau has just let the algorithms keep jumping down the temperatures from 1973. To repeat the biggest change between the raw and the new values is in 1913 when the temperature has been jumped down a massive 1.8 degree C.

      In doing this homogenization a warming trend is created when none previously existed.
      By Jennifer Marohasy.

      Seems Bill Johnston crime is not vouching for the Bureau of Meteorology claim that the weather station could have been moved in 1966 and/or 1974.

      201

    • #
      Rereke Whakaaro

      Craig,

      … considering the misleading nonsense he got caught out trying to spread

      Misdirection is so passe. You need an updated edition of Propaganda for Dummies.

      202

    • #
      Bill Johnston

      You’d find Craig if grabbed some data and analysed it for yourself, that local rainfall explains 50 to 80% of the variation in local temperature.

      That being the case it makes no sense using temperature data that are uncorrected for rainfall, to adjust temperature at another site.

      This is why for the same site, say, Rutherglen, the Bureau’s homogenised data and local rainfall are relatively poorly correlated. The Bureau first-of-all said (in the Station catalogue) that the station had never moved …. but, woops, they then said it had.

      The problems are not restricted to Rutherglen, but as I’ve said, are widespread across the Bureau’s network. I’ve shown evidence for Norfolk Island (Figure 8). Others that I’ve checked are Alice Springs, Mt Gambier, Broome, Amberley, Wagga Wagga, Laverton.

      I’ll leave you with the thought that the Bureau has a major credibility problem.

      It’s their data after all; their “world’s best practice”; their “peer-review”. They pay people to do this stuff, it should not be up to the great unpaid to do their work.

      Cheers,

      Dr. Bill

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      Egor TheOne

      You just keep on Fudging the Facts to Fit your Faith Craig !

      Thy Crusade of a True B’lver …..to go forth and beat even Stephan at ‘Red Thumbs Down’!

      You need to wrap your mind around what really matters https://wattsupwiththat.files.wordpress.com/2015/09/clip_image002_thumb1.jpg?w=597&h=279
      and let go of your Pre-Enlightenment .

      Embrace reality as we do >>> ‘CAGW = BS’

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      John Robertson

      Who is we? In your case it seems to be ;”Engage brain, before putting keyboard in gear.”
      Are you daft?
      If the miserably short record we have of daily temperatures, is made up of two distinctly different methods of measuring these temperatures, do you have one continuous record or two separate records?

      Reaction time, lag to read, is very important.
      Electronic systems stabilize in seconds.
      Mercury in glass.. minutes.. something like 10 minutes on temperature fall, a shorter reaction on temperature rise.
      So in the early afternoon just before the thunder storm , when the surface temperature gets intensely hot for a few minutes before the thunderheads let go.
      Which system do yah think might read a record, especially when compared to the slower?

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    mark

    The smoking gun!

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    David-of-Cooyal in Oz

    Thank you Bill, for all that work, and thank you Jo, for publishing it here. For me it was a “dah!!” moment, as in “I really should have known that”. For example: it rained here last night, and I can see rain drops on the leaves of the grass, which seems to be growing as I watch. So I guess poor old Sol has to burn off that water even before its energy gets stolen for photosynthesis. No wonder it takes a while to warm up after rain.
    But even if I’d formulated the connection I wouldn’t have got to a publishable paper. So thanks again Bill.
    Cheers,
    Dave B

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    RB

    Firstly. Thanks to Bil Johnston for putting in the effort of doing a thorough analysis to pursue a gut feeling because it is a lot of work.

    I don’t think that spikes are the reason that AWS read higher. I noticed a step up in many stations about the same time as AWS were introduced and that the official maximum temperatures were higher than the highest reading (usually half hour intervals). I don’t know if that was due to a spike in temperatures recorded but not published but I found it strange that the mean of the official max and min for the day was closer to the mean of all half hour readings than the mean of the highest and lowest recorded. Never got around to putting in the hours to investigate it furthers so once again, thanks to Bill and everyone else who does.

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    Ken Stewart

    Well done Bill. I will revisit my comparisons with UAH data now as a result.

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    Ken Stewart

    In reply to Graig Thomas’s many comments above:

    The net effect of BoM’s work here is also very slightly on the cooling side.
    (This is why people who hate BoM so much don’t look at the overall results, but instead cherrypick a handful of stations whose records suit their arguments.)

    Sorry Craig, not true. The net effect of BOM’s homogenisation across the network is substantial warming of trends in minima and maxima.

    The public is perfectly satisfied with our BoM – one of the world’s best scientific organisations.
    You and this Johnston joker are waaaaay out on the fringe with this.

    The public will become much less satisfied when the media publicise more of the many faults being found. Just because you’re satisfied doesn’t mean everyone else is.

    Of course they are accountable – their methods are checked and tested internationally.

    That’s why the 2011 review failed to detect 954 instances of daily minima higher than maxima in Acorn- the first and most important test of internal consistency? And how exactly would you check their adjustment of daily data when for many of the sites there are NO digitised daily raw data to compare with, for up to nearly half of the record?

    I don’t see why we would listen to what Johnston has to say, considering the misleading nonsense he got caught out trying to spread about Rutherglen.

    So instead of critiquing the findings, the data, the methods, you resort to personal attack, and a vague and irrelevant reference to some unspecified past misdeed.
    Sorry pal, toy’re the one we shouldn’t listen to.

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      handjive

      Dunno why I wasted time on this.
      I blame Ken and his use of the words Craig & vague.
      And I blame Ruari.
      . . .
      There once was a fellow named Craig
      With comments that were always vague
      Deep in deniance
      He was short on good science
      And ad hom was his stock in trade.

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    PeterS

    So what happened to the notion of homogenization to “make all data equal”? They should convert raw electronic temperatures to conventional data first before doing anything else if they are to analyses the long term historical trends. One does not need a PhD in Science like myself to know this. I consider their tactics unscientific to the extreme. If I were a Professor and had to review the final work of a PhD student using mixed digital and analogue data they way the Bureau is doing it I would throw the work out and tell him or her to start again from scratch. This is more proof why science today is not real science but quackery and deliberate deception to cover up the truth.

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    Ruairi

    The Bureau must find a warm trend,
    For fear that their tenure might end,
    As the powers that be,
    Through the I.P.C.C.,
    Need a graph with a hockey-stick bend.

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    As soon as you hear people like Craig Thomas saying that we do not need an inquiry into the BoM, you know immediately that there is an urgent need for an inquiry into the BoM. The nett effect of the BoM’s homogenisation and TOBS adjustments over the network is a satisfying and substantial warming trend in minima and maxima, which would be otherwise totally absent.

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      ROM

      Craig Thomas as we see above in various posts is a classic example of one of those interesting psychological specimens that has done so much to hold back human progress down through the ages.

      His basic underlying psychology is that you never challenge authority or the pronouncements of the supreme, in his opinion, authorities as they are all seeing, all knowing and incorruptible in upholding the ideological foundations of their belief system.

      With the classic Craig Thomas psychology, nobody would ever have challenged the medieval Church’s absolute control over what was to be the scientific beliefs on creation, on the Earth as the centre of the entire cosmos as the church imagined it or the flat Earth upheld by angels or turtles or what ever and so much other science that changed radically with the coming of the Enlightment from 1685 on and which existed for a century and a half during which our modern science systems evolved.

      Craig Thomas’s kowtowing to authority is the type of psychology that all the past totalitarian movements were and still are utterly reliant on.
      That there were a number of individuals in a society that would support and never challenge, particularly when those nascent totalitarian movements were in their infancy, the role of the leaders nor ever question, challenge and maybe even seek to discredit the utterly ruthless empathy lacking ultimate leader in all those totalitarian movements.
      Movements which in the 20th and early 21st century encompass the rise of the Stalin’s Soviet Empire, Germany’s Nazis, Uganda’s Idi Amin, China’s Mao Communists, Cambodia’s Pol Pot which killed a third of Cambodia’s population in only a dozen years or less, the rise of Islamic terrorism and the Taliban and ISIS, all of whom who have a supreme leader psychology unto whose pronouncements all must adhere without question.

      The world of science and technology, of social progress , of equality of sex, race and men plus science and technology, the whole civilisation and the living standards we now have in this current Age would have never have arisen or evolved if the abject kow towing to authority psychology of the Craig Thomas’s of this world had remained the dominant psychological theme of mankind down through the ages.

      His particular brand of unquestioning belief in the supreme knowledge and power of authority and the absolute heed and kow tow to that authority be it more lilely than not to be utterly corrupt and deadly in its pursuit of power is the very basis of so much of the strife and anguish that has been the sad lot of mankind down through the ages.

      Science is the first expression of punk, because it doesn’t advance without challenging authority. It doesn’t make progress without tearing down what was there before and building upon the structure.

      Greg Graffin

      Or this quote which seems so applicable to the Craig Thomases of this world.

      The consuming desire of most human beings is deliberately to plant their whole life in the hands of some other person. I would describe this method of searching for happiness as immature. Development of character consists solely in moving toward self-sufficiency.

      Quentin Crisp

      And that is why we are called “Skeptics”

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    Bill exposes the false god of temperature.

    We cannot determine heat flux if we fail to consider the heat content of the air and the margins of error inherent in the respective instrument records.

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      Bulldust

      Well said Bernd – your piece hits on a lot of the issues I have with “average global temperture anomolies” calculated from poorly distributed and positioned thermometer readings. Perhaps it is the best they have, but the measures are woefully unhelpful for scientific use IMO.

      Temperture data _may_ have something useful to say about the mricoclimate around that station. That’s it. To extend it to hundreds or thousands of square kilometres and then blend it with surrounding station data… the mind boggles.

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        Rereke Whakaaro

        To extend it to hundreds or thousands of square kilometres and then blend it with surrounding station data… the mind boggles.

        “If you tell a lie big enough and keep repeating it, people will eventually come to believe it. The lie can be maintained only for such time as the State can shield the people from the political, economic, [scientific,] and/or military consequences of the lie. It thus becomes vitally important for the State to use all of its powers to repress dissent, for the truth is the mortal enemy of the lie, and thus by extension, the truth is the greatest enemy of the State.”

        Joseph Göbbels

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        Greg Cavanagh

        Adding the temperatures of tropical islands with Arctic mountains…. makes zero sense scientifically, and tells you exactly squat.

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      RB

      I wish that I had that link when replying to a comment from Willis at WUWT about how you they use average concentrations to analyse the potential yield from an ore body.

      Concentration is simply mass of a component divided by the total mass and yet its quite complex to get a useful average from samples that is close to value when measured for the whole body. Its stupid to think that you can do it with any intrinsic property (that, strictly, should be constant within the whole sample for it to be an intrinsic property) especially temperature.

      It’s that simple. Meticulous and rigourous, but simple.

      I suspect that even then it is still wishful thinking.

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        I suspect that even then it is still wishful thinking.

        It’s an idealised scenario.

        The real problem is social: The people being paid to do the job aren’t even trying to do proper job. They just do “something” to get by and produce results that please their paymasters.

        I reminds me of a sour experience in chemistry lab when the supervisor didn’t understand how cumulative errors in measurement meant that writing down results to 5 significant digits was wrong; even when the result looked right.

        In retrospect, it taught me about desirable results and why people produce them; even when there’s no physical basis for them.

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        gai

        On Krigging:
        “…about how you they use average concentrations to analyse the potential yield from an ore body….”

        A geostatistian explains why it is wrong and the gold mine [selfsnip] that was caught.
        https://web.archive.org/web/20141111203721/http://geostatscam.com/sampling_paradox.htm

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    handjive

    If the sale of carbon(sic) credits failed to stop the drought the first time around, why would you do it again?
    . . .
    THE federal government has spent another $557 million purchasing 45 million tonnes of carbon abatement at the second emissions reduction fund auction.

    According to one winning company that represents 36 graziers in Queensland and NSW with $120 million worth of contracts, it has come at the right time for those struggling through drought.

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      handjive

      If the Australian Talkbull Gov’t is buying carbon(sic) credits from the United Nations – EU:

      “According to a study from leading global environmental think tank, The Stockholm Environment Institute, 73% of carbon credits created under the Kyoto Protocol’s Joint Implementation program did not deliver “plausible” emissions reductions.
      According to the researchers these projects were going to happen anyway.

      “The implications are particularly serious for the EU ETS.

      Almost two-thirds of JI credits were used in the EU ETS, so the poor overall quality of JI projects may have undermined the EU’s emission reduction target by some 400 million tonnes of CO2”.

      businessspectator.com: 73% of UN Joint Implementation credits deliver no climate benefit

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    King Geo

    I see in todays MSM that Rudd is giving PM Turnbull some “Climate Advice” before he heads off to COP21 early next month.

    LOL

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      King Geo

      I see in todays MSM that Rudd is giving PM Turnbull some “Climate Advice” before he heads off to COP21 early next month. Mmmmm!!!

      LOL

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      handjive

      If you need advice on the mating habits of rats in cold environs, Kevni’s your man.

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    Min/max, in those more humid places where humans prefer to live, is too often just a measure of how high or low the temp was allowed to go by cloud cover. The fact that so many experts seem to have overlooked or ignored this giant fact is an indication of how much intellectual trouble we are in. The physical climate is okay, considering what the rest of the Holocene Epoch has been like, but the intellectual climate is a total stinker.

    I wonder. When I’m in Sydney I notice that a great number of the more educated males around the urban fringe wear scarves and woollen beanies even in the heat of summer. Could this be distorting their perception of temperature?

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    pat

    go to the link…

    11 Nov: UPI: Brooks Hays: Idea of slow climate change in the past is flawed, researchers say
    It isn’t the rate of climate change that’s changed, but our view of time.
    NUREMBERG, Germany, Nov. 11 (UPI) — Climate scientists have mostly been operating under the assumption that climate change in the past happened at a much slower pace than the changes being witnessed today. But researchers in Germany say that assumption is false…
    As explained in new paper on the subject, published in the journal Nature Communications (LINK), the issue is perspective…
    http://www.upi.com/Science_News/2015/11/11/Idea-of-slow-climate-change-in-the-past-is-flawed-researchers-say/5681447257780/

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    pat

    o/t but always happy to post Tony Thomas:

    12 Nov: Quadrant: Tony Thomas: House of the Climate Kleptos
    Very soon, Malcolm Turnbull will jet off to Paris with the taxpayers’ chequebook and a store of telegenic sound bytes hailing Australia’s generosity in ameliorating the injustice of climate change’s impact on the Third World. Thieves, rorters, scam artists and assorted corruptocrats will cheer lustily
    http://quadrant.org.au/opinion/doomed-planet/2015/11/house-climate-kleptos/

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    Egor TheOne

    This Sketch says it all >> https://stevengoddard.files.wordpress.com/2014/08/screenhunter_1871-aug-11-08-19.gif?w=640&h=568

    Even though this is relevant to the USA , it is the same story everywhere ….’If the Facts don’t fit the faith , then the facts get fudged till they do’ .

    Data tampering within this entire CAGW debacle is common place , not rare .

    Hansen’s manipulations are classic …..every few years they get readjusted to reinforce the their CAGW BS fantasy !

    There are only 2 reliable temp data sets , of which are the satellite sets , which measure the land and surface temp of the entire planet except for the polar regions ,and both show no warming for nearly 19 years .

    https://wattsupwiththat.files.wordpress.com/2015/09/clip_image002_thumb1.jpg?w=597&h=279

    Local and other land based are as reliable as M.Mann’s infamous Hockey Stick deceptive fabrication,the hockey stick image of which was quietly and conveniently excluded from the IPCC’s own Logo !

    We don’t put satellites into orbit at billions of dollars cost ,because the same can be achieved with land based thermometers .

    In addition there is no ‘Mike’s little nature trick’ with the Sat Data !
    I know which sets I trust , and they are not the ‘Homogenized’ ,that are conveniently not allowed to be scrutinized !

    It amazes me how a PhD skeptic will not get listened to ,but some GetUp True B’lver clown does .

    This is not Science , This is a political agenda with big financial and multinational interests ……. A global Racket .

    http://jo.nova.s3.amazonaws.com/art/cartoon/steve-hunter/Jedi%20Mind%20Trick_fools.gif

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    pat

    12 Nov: Wyoming Business Report: Mark Wilcox: JH scientist: Greenhouse gases’ effect minimal in global warming
    A retired Jackson Hole scientist is anteing up $10,000 of his children’s inheritance to try to disprove the foundations of current global warming theories that tie it to greenhouse gases.
    Dr. Peter Ward, who retired in 1998 after 27 years with the U.S. Geological Survey, has spent a good deal of his retirement exploring global warming. His years of research, reading thousands of scholarly articles and many books, have led him to a different conclusion than the consensus opinion.
    “There’s been a big effort over the last 25 years to build consensus around the greenhouse gas theory so politicians would take action,” Ward said in a phone interview Thursday. “I’m fighting that consensus at the moment.”
    He said the foundational understanding of greenhouse gases as the culprit for global warming is flawed.
    “There has never been an experiment done that if you increase the concentration of carbon dioxide in the atmosphere that the air would get warmer,” he said.
    With that in mind, he has said if someone can prove experimentally rather than theoretically that greenhouse gases cause more global warming than ozone depletion, he will fork over the $10,000. He doesn’t anticipate spending the cash…
    http://wyomingbusinessreport.com/jh-scientist-greenhouse-gases-effect-minimal-in-global-warming/?utm_medium=email&utm_source=newsletterthursday&utm_term=2015-11-12

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      ianl8888

      I wonder if the $10k is as empirical as the evidence required to get hold of it 🙂

      Nonetheless, I’m chuffed that a geo has put up this challenge … very entertaining

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    pat

    the battle is on:

    12 Nov: NYT:AURELIEN BREEDEN: Any Paris Climate Deal Must Be Legally Binding, French Leader Says
    French officials said on Thursday that any agreement at the coming climate conference in Paris would have to be legally binding, expressing alarm at comments by the American secretary of state that suggested the opposite.
    President François Hollande of France, speaking to reporters at a summit meeting of European and African leaders in Malta, said that “if the agreement is not legally binding, there is no agreement,” because there would be no way to verify that countries had enforced their pledges…
    The French foreign minister, Laurent Fabius, speaking on the sidelines of the summit meeting in Malta, which focused on migration, described Mr. Kerry’s choice of words as unfortunate. “There are going to be discussions between jurists on the shape of the agreement, that is not a surprise,” he said, “but the discussions in Paris must produce tangible results, and that is not debatable.”
    “This is not a hot-air political discussion,” he added. “This is a real agreement.”
    In Washington, State Department officials were quick to clarify Mr. Kerry’s position.
    “The F.T. interview with Secretary Kerry may have been read to suggest that the U.S. supports a completely nonbinding approach,” a State Department official said, speaking on the condition of anonymity because the department had not released an official statement on the matter. “That is not the case, and that is not Secretary Kerry’s position. Our position has not changed: The U.S. is pressing for an agreement that contains both legally binding and non-legally binding provisions.”…
    http://www.nytimes.com/2015/11/13/world/europe/any-paris-climate-deal-must-be-legally-binding-french-leader-says.html?_r=0

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    liberator

    Surely the AWS thermometers controlled by the BOM are calibrated against national reference standards, e.g. through NIST? If they are then they know what the error is. And what is the BOM’s tolerances on this error? Do they regularly monitor and check their thermometers and replace defective ones that fail to meet their standards. And are any of the results produced by that sensor then discarded as the data is unreliable? If they do check their sensors against a known standard then how frequently is this done? I know they were certainly happy enough to use another AWS rainfall results that’s 30ks away from an AWS that had failed to record the rainfall due to a seed getting stuck in the rain gauge. We had 100mm in 24 hours the AWS 30 ks away had 40 – but our official records show we had 40mm because they used the working AWS results. I suppose they could have smoothed, homogenised and adjusted our records to fit….oh they did.

    A daily temperature result to be recorded correctly should be for example 26.5°C +/- the error.

    No instrument can give an absolute value – there is always an error in a measurement. So when we see its the hottest XXX and its 0.02°C above, what is the error of that recorded result.

    Like I said there are no absolute results in measurements, there is always a value of uncertainty.

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    • #
      Bill Johnston

      Hi liberator,

      Its not about calibration, which is done in a lab; its about field performance and the main issues are that AWS thermometers are (i) almost universally housed in small screens; (ii), they sample every second and (iii) their calibration is non-linear (quadratic). I tested a range of commercial units at Wagga Wagga in the 1980’s by comparing their daily estimates (max, min and average) with thermometers housed in large Screens.

      Electronic probes were prone to over-shooting their calibrations on warm days. Spikes affected Tmax especially; and also Tmean but often not Tmin, mainly because Tmin was sensed within their working range.

      The Bureau’s Automatic weather stations have a single probe sampling both-tails (upper-Tmax; lower-Tmin) of the distribution of ‘samples’/day.

      On warm days, the upper-tail tends to spike. Daily values of Tmax and Tmin, can be further examined (separately) as over-range and under-range counts/year (see for instance Figure 10 in the pdf).

      These various data attributes can be anslysed. The evidence is convincing.

      The Bureau also knows about the problem (http://www.abc.net.au/news/2015-01-21/bom-withdraws-alice-springs-hottest-day-record-advice/6030090); its not a faulty thermometer is’s a bad habit.

      Cheers,

      Bill

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      • #

        I tested a range of commercial units at Wagga Wagga in the 1980′s by comparing their daily estimates (max, min and average) with thermometers housed in large Screens.

        Sir Charles Todd did side by side tests of a Sling Psychrometer and Stevenson screen and two styles of Glaisher stand over many years at West Terrace Adelaide. From these tests it is easy to see that the Stevenson screen is undershooting maximums compared to the Sling Psychrometer. The Sling Psychrometer gets a more accurate reading of the air temperature than any stand or screen because of the forced air flow.
        From the comparisons to the Glaisher Stand it can be seen that the Stevenson is giving artificially higher readings in the minimums than reality also. This is obviously an error in the Stevenson because the Glaisher has no side louvres to exchange heat with the air before it gets to the thermometer. The sun can logically only be blamed for the opposite difference.
        The problem with the Stevenson is that the large surface area of louvres acts like heatsink cooling fins to spread the cooling or warming thermal momentum of the huge 1700 J/kg/Degree wooden box over a lot of air volume quickly before it gets to the thermometer.

        AWS thermometers are (i) almost universally housed in small screens

        For good reasons too. That is a great improvement!
        As you are showing Bill the result is that the past maximums read cooler from the Stevenson than the AWS but the old minumums should read higher because the Stevenson’s massive heat storage perverted both in opposite directions.
        https://www.youtube.com/watch?v=Sxm6yq268Bc

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      Rich

      Just what are the specifications for the accuracy for theses instruments? I calibrated instrumentation used a power plants to measure plant operating parameters. The “calibrating” equipment had specifications indicating that the accuracy was only within specifications when, and only when, the test instrument was in an environmentally controlled area with the supply voltage within 10% of the required voltage. With the room temperature more than 5 degrees below/above the specifications the calibration could not be performed.
      Thus if you take one of these “laboratory standard” devices and place it out in a weather station enclosure the electronic equipment will be subject to the same temperature as what you are measuring. The only time it will be providing accurate readings is when the equipment is at the same temperature as when it was calibrated. the further away it is from the calibrating temperature the less accurate it will be.

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    JohnM

    This falls into the “NS Sherlock” category. Rain comes from clouds .. clouds block solar radiation (as Jo’s series of posts said) … and maximum temperatures won’t be as high under cloud as they are under clear skies.

    Rain will also mean surface and plant moisture. The evaporation of these will use solar energy, meaning that the energy won’t be used to elevate temperatures, so less input available to cause heating means less heating. It’s basic hydrology.

    If you recall a few years ago that bright spark David Karoly insisted that higher temperatures caused droughts. That only goes to show how little he knows. Mind you did he change his story when corrected but someone more qualified? No.

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      gai

      Actually it is the latent heat of vaporization.

      If the humidity is 50% or 80% instead of 0% then part of the energy from the sun is locked into the latent heat of vaporization. Clouds are a separate issue in that they reflect incoming solar energy back to space. OR they can reflect out going energy back to earth.

      Think of a boiling kettle. The temperature doesn’t increase until all the water is vaporized. Increasing the heat on the stove makes no difference because the energy is going into causing the water to change state.

      So energy in the atmosphere = temperature + energy as latent heat of vaporization

      With the same incoming energy the temperature can change as the amount bound in the latent heat changes. This is why deserts are so much warmer in the day and then cooler at night than tropical rain forests (dew forms releasing heat) even when there are no clouds.

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    pat

    ***”drastic measures” called for!

    12 Nov: Deutsche Welle: Mara Bierbach: Climate change could pummel stocks: study
    Environmentalists aren’t the only ones fretting over climate change. A new study has calculated the risk to financial markets if temperatures are allowed to rise uninhibited. Inaction, it said, would be a bad investment.
    A fresh study by the Cambridge Institute for Sustainable Leadership has put a price tag on climate change mitigation. Investment portfolios primarily made up of stocks could lose nearly half of their value if global warming isn’t curbed.
    By contrast, if the Earth’s temperature is prevented from rising more than 2 degrees above pre-industrial levels, global GDP could be 20 percent higher in 2050 than it is now, according to the study, which was released on Thursday…
    The study posits that radical political measures to mitigate climate change would initially have a negative impact on the real economy and the financial sector. Yet, in the long term, global economic output would benefit from limiting global warming to two degrees Celsius above pre industrial levels…
    Scott Kelly, one of the authors, sees the study as yet another reason for policy makers to commit to ***drastic measures at the upcoming UN climate conference in Paris…
    http://www.dw.com/en/climate-change-could-pummel-stocks-study/a-18845738

    12 Nov: Cambridge Institute for Sustainability Leadership: Climate change sentiment could hit global investment portfolios in the short term (report)
    The report, “Unhedgeable risk: How climate change sentiment impacts investment (LINK),” concluded that about half of this potential loss could be avoided through portfolio reallocation, while the other half is “unhedgeable”, meaning that investors cannot necessarily protect themselves from losses unless action on climate change is taken at a system level…
    About the report “Unhedgeable risk: How climate change sentiment impacts investment” was commissioned by the ***Investment Leaders Group (ILG) and the Cambridge Institute for Sustainability Leadership (CISL). The study was conducted by three University of Cambridge research institutions: the Centre for Risk Studies (CRS), the Centre for Climate Change Mitigation Research (4CMR) and the Judge Business School.
    http://www.cisl.cam.ac.uk/business-action/sustainable-finance/investment-leaders-group/news/climate-change-sentiment-could-hit-global-investment-portfolios-in-the-short-term

    ***members of Investment Leaders Group includes Allianz, Aviva, PensionDenmark, TIAA CREF, Zurich, etc

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    TdeF

    That’s a very good point about spikes in temperatures. It is a bit like CO2 levels from ice cores, the leakage of CO2 produces averaging and spikes will vanish, which in turn means CO2 does not spike over a hundred years in response say to changes in sea temperatures.

    Modern high speed and tireless and perpetual instruments must pick up changes over a few minutes which are not picked up by old bimetal strips and thermometers and slow response devices. The coincidence between sudden warming followed by a sudden stop in warming indicates a change in instrumentation. Unless they are averaged to match previous readings, dealing with minima and maxima must be affected.

    Why people care more about location changes, real or imagined is a puzzle. After all I have read arguments that a move of a few metres changes readings which are presumed to be good to represent real temperatures over a few hundred kilometers in radius, thousands of square kilometers? You have to wonder where we would be if it was not for satellites.

    Then as the planet refuses to warm as predicted by every model, you have to question whether it actually warmed at all. The refusal by the BOM to consider any temperatures prior to 1909 is amazing. In this they betray the trust of all the thousands who faithfully recorded State temperatures before Federation and also ignore utterly the devastating Federation drought, which looks to have been hotter and longer and drier than the recent drought.

    Are we to believe all this is innocent or that the world meterological society expects Australia to do its bit to support the IPCC as the major source of land data South of the Tropic of Capricorn? How many BOM people go to Paris? Why is our PM going? Is everyone going to Paris? We sent 120 people to Copenhagen and how did that work out? Is it jolly party time again while the conference on the mass murder in Syria is ignored? What science ignorant person decided Carbon dioxide was the greatest threat to mankind when we are made entirely from the stuff?

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      TdeF

      Brilliant. So what was unquestioned truth in 2000 is now an utter embarassment. Was it peer reviewed? Was it accepted science? How could a professional climate scientist speaking on behalf of his centre be so completely wrong or is that normal? Worse, not one of his peers at the CRU called it out then or now as untrue let alone ridiculous. It shows they never let the facts get in the way of a good scare.

      As for Antarctic ice recently at record levels, some are saying (ABC) that it is losing ice and others that it is massively gaining ice and it is possibly responsible for recent dip in sea levels. However as National Geographic demonstrates in their entirely one sided COOL IT November issue, there is no other side to the story. We are all going to drown or die in hell fires because of CO2. This issues of National Geographic will go down in history as comedy along with their hoax based feathered dinosaur issue, but this one just in time for Paris. In the new world of political science, who needs facts when you have emotion?

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    paul

    hi jo

    i did a google search “greenpeace banned in india” of Australian news outlets and not one entry came up.

    OMG

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    pat

    paul –

    Australia’s CAGW-infested MSM doesn’t report anything that doesn’t fit the warmist narrative; hence the Australian public is ignorant of developments such as UN climate chief, Christiana Figueres, stating –

    27 Oct: Reuters: Climate change deal will not include global carbon price-UN climate chief
    A climate change deal to be agreed in Paris in December will not be able to come up with a global carbon price, the United Nations’ climate chief, Christiana Figueres, said on Tuesday…
    “(Many have said) we need a carbon price and (investment) would be so much easier with a carbon price, but life is much more complex than that,” Figueres told a climate investor event in London.
    “I agree it would be more simple … but it’s not quite what we will have,” she said, adding that the world would move towards that in the future…
    http://af.reuters.com/article/commoditiesNews/idAFL8N12R37S20151027

    because ABC didn’t report that, they are able to carry on with rubbish such as:

    12 Nov: ABC Lateline: TONY JONES: Does Australia have any – you talk about ethics a lot in your recent speech on climate change. Does Australia have an ethical duty to not export so much coal to India?
    KEVIN RUDD: I think the bottom line with the source of all dirty carbon exports, of which coal, oil and gas descend in that order, is to make sure that there is a very clear global carbon price, and therefore, that it becomes ultimately too expensive to consume these environmentally-corrosive energy sources…
    http://www.abc.net.au/lateline/content/2015/s4351389.htm

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    pat

    similarly, our MSM appears to have ignored John Kerry’s Financial Times article: “Paris climate deal will not be a legally binding treaty” in which he stated there was ““not going to be legally binding reduction targets like Kyoto”. Hollande hit back today, but how can our media now carry Hollande, if they haven’t reported Kerry?

    all the heavy-hitters at AP have been brought to bear for this one:

    12 Nov: ABC America: AP: Seth Borenstein: CLIMATE COUNTDOWN: When’s a Warming Treaty Not a Treaty?
    (Matthew Lee and Donna Cassata in Washington, Angela Charlton in Paris and Karl Ritter in Stockholm contributed to this report.)
    It’s the elephant in the negotiating room that few officials want to acknowledge: Whatever international deal comes out of Paris climate talks, it likely won’t be a treaty that needs ratification by a reluctant Republican U.S. Congress.
    That’s not the only complication in Paris. China, the U.S. and India don’t want the international community dictating their carbon dioxide emissions, but they do want to do something about ever escalating greenhouse gas levels and the rising temperatures they cause. So they have to come up with an agreement that doesn’t dictate binding, internationally set targets or require U.S. Senate approval — and yet gets the job done. At least partly.
    To do so, they must reach a pact that has as many twists and turns as a pretzel…
    And here’s the twist: Both Kerry and Hollande can be right, said Nigel Purvis, an international lawyer who was a top environmental diplomat and international negotiator for Bill Clinton and George W. Bush. It’s an issue of definitions and the way an agreement is framed, said Purvis, who is president of the non-governmental organization Climate Advisers.
    The U.S. Constitution and the rest of the world have different definitions of the word “treaty,” Purvis said. Elsewhere, a treaty is a binding agreement. But in the U.S., there are several types of international agreements and only 6 percent of them end up being formal treaties that require Senate approval, he said. The last international, Senate-approved treaty was in 2010.
    The climate treaty, Purvis said, is likely to end up as an “executive agreement” like the 1945 Yalta Accord at the end of World War II. This requires only presidential approval…
    Purvis said it probably will hinge on a 1992 international treaty, signed by President George H.W. Bush and approved by the Senate, that promised to do something about climate change; a decades-old U.S. air pollution law; a U.S. Supreme Court decision that said the air pollution law applies to carbon dioxide; and presidential executive action…
    http://abcnews.go.com/Technology/wireStory/climate-countdown-whens-warming-treaty-treaty-35165698

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    pat

    another story most MSM, with the exception of UPI in the US, are not carrying because it doesn’t fit with the Trudeau Climate Saviour narrative:

    12 Nov: Huffington Post: Steve Horn (Desmog): TransCanada’s Next Move After Keystone XL: Flood Mexico with Fracked Gas With State Department Help
    TransCanada, the owner of the recently-nixed northern leg of the Keystone XL tar sands pipeline, has won a bid from Mexico’s government to build a 155-mile pipeline carrying gas from hydraulic fracturing (“fracking”) in the United States to Mexico’s electricity grid.
    The company has benefited from Mexico’s energy sector privatization promoted by the U.S. State Department, the same agency that denied a permit to the U.S.-Canada border-crossing Keystone XL. TransCanada said in a press release that construction on the $500 million line will begin in 2016 and it will be called the Tuxpan-Tula Pipeline.
    This is not the first pipeline system TransCanada will oversee in Mexico. The company already owns four other systems, with two operational and two under construction. But it is the first pipeline the company will own during Mexico’s energy sector privatization era, a policy in place due to constitutional amendments passed in 2013…
    As Bloomberg explained in a November 10 article, Mexico’s consumption of U.S. fracked gas will keep the U.S. shale gas industry and fracking afloat during a time of depressed prices on the market…
    http://www.huffingtonpost.com/steve-horn/transcanadas-next-move-af_b_8539918.html?ir=Australia

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    pat

    can you believe Rasmussen has this headline? it’s like a psyops:

    12 Nov: Rasmussen: Little Support for Punishing Global Warming Foes
    Global warming advocates are calling for the prosecution of groups who disagree with them, and New York State has taken it a step further by investigating Exxon Mobil for refusing to play ball with the popular scientific theory.
    But 68% of Likely U.S. Voters oppose the government investigating and prosecuting scientists and others including major corporations who question global warming. A new Rasmussen Reports national telephone survey finds that 17% favor such prosecutions. Fifteen percent (15%) are undecided. (To see survey question wording, click here.)
    Just over one-in-four Democrats (27%), however, favor prosecuting those who don’t agree with global warming. Only 11% of Republicans and 12% of voters not affiliated with either major party agree…
    Most voters across nearly all demographic categories agree that the scientific debate about global warming is not over.
    Most also oppose prosecuting those who don’t agree that global warming is real, although voters under 40 are more supportive of prosecution than their elders are…
    http://www.rasmussenreports.com/public_content/politics/current_events/environment_energy/little_support_for_punishing_global_warming_foes

    Rasmussen: Questions – Global Warming – November 9-10, 2015
    1* Is the scientific debate about global warming over?
    2* Should the government investigate and prosecute scientists and others including major corporations who question global warming?
    http://www.rasmussenreports.com/public_content/politics/questions/pt_survey_questions/november_2015/questions_global_warming_november_9_10_2015

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  • #
    Peter Azlac

    Craig Thomas Says
    “Interesting, although I notice all your links are links to blogs. Does this information about Klaus Hager have a reputable source you can refer us to? Presumably this valuable research has been published?”
    Klaus Hager is a 44-year veteran German meteorologist compared to those modelers who sit indoors and create models to adjust the temperature data to support the AGW meme. Further, the test covered 3134 days at an official WMO meteorological station- Fliegerhorst Lechfeld (WMO 10856 where apparently unlike every other meteorological station in the NCDC WMO list (that is the basis for the GISS, NOAA , CRU and BEST temperature series) they carried out the good practice of running the two systems side by side. If that had been done at other stations there would be no need for models to correct the trend by guessing at biases.

    http://notrickszone.com/2015/01/13/weather-instrumentation-debacle-analysis-shows-0-9c-of-germanys-warming-may-be-due-to-transition-to-electronic-measurement/

    Hager is not alone in his criticism of the accuracy of digital thermometer systems. A peer reviewed study by Lin and Hubbard concluded:
    “Therefore, the RSS errors in the MMTS are from 0.31° to 0.62°C from temperature -40°C to -50°C (Fig. 5).”
    And
    “For the HO-1088 sensor, the self-heating error is quite serious and can make temperature 0.5°C higher under 1 m/s airflow, which is slightly less than the actual normal ventilation rate in the ASOS shield (Lin et al. 2001a).”

    http://wattsupwiththat.com/2010/03/09/accuracy-of-climate-station-electronic-sensors-not-the-best/

    They point out that digital systems are prone to errors through poor ventilation of the shield and direct effects of IR from buildings, and other heated surfaces. Since many, if not most, digital stems are sited either by building or near runways the latter is a serious problem as shown by the “record” temperature at Heathrow in July that was 1.4 C warmer than nearby Kew Gardens and Northolt.

    https://tallbloke.wordpress.com/2015/07/01/heat-wave-day-2-heathrow-airport-about-36c/

    Also, in a peer reviewed study “Air Temperature Comparison between the MMTS and the USCRN Temperature Systems” HUBBARD et. Al. concluded:
    “Although the MMTS temperature records have been officially adjusted for cooler maxima and warmer minima in the USHCN dataset, the MMTS dataset in the United States will require further adjustment. In general, our study infers that the MMTS dataset has warmer maxima and cooler minima compared to the current USCRN air temperature system.”

    http://www.homogenisation.org/files/private/WG1/Bibliography/Applications/Applications%20(F-J)/hubbard_etal.pdf

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    Roy Hogue

    Someone stop me if I’m wrong but…

    1. The electronic temperature sensor can probably be read to greater precision than the mercury thermometer if it can be kept calibrated and should be superior for that reason.

    2. The electronic sensor can be read remotely, which is a very useful convenience.

    3. But the electronic sensor adds a bias to the reading.

    Have we shot ourselves in the foot by changing to the theoretically superior electronic sensors?

    And I’m not sure I understand the theory behind the added bias from the electronic sensors.

    It’s easier to see how rainfall could affect the readings. But then the rain gauges suffer from the maintenance problem — overgrown with weeds if not kept cleared.

    This looks like the same kind of catch-22 we’ve seen all along with poor placement of sensors and thermometers.

    Is this verification of the principle in physics that the very act of measuring something will modify what you’re measuring? 😉

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  • #
    Peter Azlac

    There are a couple more direct examples of side by side comparisons of MMTS and LIG units over periods of years. But these are for units that are sited according to WMO standards, and few are being close to buildings and above or near concrete, asphalt with high IR emissions.
    Impact of MMTS on the New Brunswick Climate Record
    http://climate.rutgers.edu/stateclim_v1/robinson_pubs/non_refereed/Croft_and_Robinson_1993.pdf
    MMTS maxima 0.6 lower and minima 0.3 higher when placed alongside LIG units in Cotton shield away from buildings.
    The National Weather Service MMTS Colorado State Doesken
    https://www.google.com/search?q=National+Weather+Service+MMTS+%22Doesken%22&gws_rd=ssl
    Found mean max of -4C and mean min of +3C but the mean range of cool maximum values was from -0.4 to -0.7F with occasional -1.7F and for minima -0.1 to -0.3 F in winter and + 0.2 in summer

    This study demonstrates a major problem with MMTS units in that they do not show a consistent difference with LIG units, with greater variance in winter and autumn months due to IR responses to changes in ground cover e.g. snow. This means any correction is station and season specific and cannot be generalized.

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    • #
      Bill Johnston

      Pretty handy info here.

      Remember here in OZ, 3 things are operating together: the PRT; small Stevenson screens and accurate high-frequency measurements (1 Hz, reported accuracy better than 0,01 deg.C.).

      The Bureau designed its PRT, they are manufactured locally and calibrated by the Bureau both in their lab and in the paddock by their staff.

      There is evidence of data spikes, but that does not necessarily implicate the PRT (could be the screen for instance).

      Data over-ranging mostly affects upper Tmax extremes (temperatures measured in the Tmax range). Rutherglen (Figure 5 in the Report is an example); Norfolk Island (Figure 8) is not.

      At Cape Otway (Figure 10), counts of high Tmax extremes increase markedly after the AWS was installed. (Not shown is that after the AWS becams primary at Melbourne RO, Tmax upper-extremes increased almost-10 fold relative to Tmax lower extremes.)

      There is an up-step across the network in 1997, which is detected statistically. The Bureau also says that Australia’s 10 hottest years “on record” have all occurred in the last 16 years, which is during the AWS-era.

      Closer examination of data they present related to their “record-hot-years” show individual stations whose records have been “broken” are all AWS stations.

      There is a second-line of evidence. AWS temperatures are not just higher than thermometer values in the time-domain (tested using serial tests); they are also higher in the rainfall domain (tested using multiple linear regression). Lines are parallel, meaning the offsets reflect differences in technique.

      As opposed to ‘technique’ being a random factor – some up, some down, which would implicate site differences/effects; for a given level of rainfall, AWS data are invariably warmer.

      Furthermore, AWS data are not as closely [linearly] related to local rainfall as thermometer data are, but show curvature (low rainfall years are non-linearly warmer (see Figure 7).

      Furthermore again, for many sites examined, “record” hot years, which has become the Bureau’s latest catch-cry are well out-of-range compared with the rainfall for those years. Their data is not coherent with rainfall data for the site in those years. In Figure 7 for instance, rainfall for Rutherglen was near-average in 2013 and 2014; at Ceduna it was above average.

      Laws of thermodynamics seem not to constrain our Bureau’s over-marketing of improbable “records”.

      (Even Craig Thomas should be able to connect some dots!)

      Cheers,

      Bill

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    ralph ellis

    Just a thought.

    The best thing to do is find a cast-iron case. A weather station that has had particularly dodgy adjustments made to it. And push for answers to that, both from the media and from parliament. It makes it easier for the public and parliamentarians to understand a single incident of error.

    Once you get an admission of a fault on one station, (“one isolated incident”), you can then push all the others forward and declare this to be a systemic problem. They then cannot say there is NO problem, because you have already established that there IS a problem.

    Ralph

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    robin evans

    Bertha Blither from Bulli Pass
    Stepped in the water up to her ankles.

    At the present rate of sea level change this little ditty will not rhyme until about 2300 A.D.

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    Gregg Armstrong

    Data sets of liquid-in-glass manual temperature recordings and electronic automated weather station (AWS) temperature recordings are completely different animals, for a variety of very valid reasons that others have already pointed out.

    More importantly, focusing on temperature measurement data alone are very misleading. Dr. Johnston’s paper, “On the quality of Australia’s temperature data”, explicitly addressed rainfall and temperature, but did not make the explicit connection to the importance of total air mass.

    Simplistically, In the steady-state case, discarding partial derivatives, the Earth’s energy balance can be calculated as:

    (E in) – (E out) – (E acc) = 0

    where:
    (E in) is the energy input
    (E out) is the energy output
    (E acc) is the total amount of energy accumulated, and

    (E acc) = (E acc surf) + (E acc ocean) + (E acc atm)

    (E acc atm) = (E acc) – (E acc surf) – (E acc ocean)

    Where:

    E acc surf is surface mass accumulated energy
    E acc ocean is ocean mass accumulated energy
    E acc atm is atmosphere mass accumulated energy

    E in is composed of photons, or electromagnetic waves, from the Sun, that are not reflected away. E out is composed of longer wavelength photons, or electromagnetic waves, from radiating “surfaces” or “pipes”, using Dr. Evans’ term. The accumulated energy in the atmosphere is a small part of overall accumulated energy. But, temperature is only part of the term, E acc atm. Accumulated energy of the atmosphere is a function of temperature and mass for a column of air. And air mass is a function of temperature, pressure and density. Or,

    E acc atm == f (temperature, total air mass)
    == f (temperature, pressure, density)

    Air density is a function of dry air density and water vapor density. The amount of water vapor present decreases air density. That is because each H2O molecule displaces an air molecule of greater mass, whether N2, O2 or CO2.

    But, for a given temperature, the total energy content of a column of air increases with increasing water vapor density, because each water molecule contains the latent heat of vaporization. But that increasing accumulated energy is hidden from the thermometer. So, focusing solely on surface air temperature measurements, without considering pressure and density, are very misleading.

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    • #
      Bill Johnston

      It is temperature that is important, nothing else. Australians have been mislead into believing that temperature has increased since ~1950.

      Temperature (Tamx and Tmin) is measured under standard conditions (at 9AM local time, within a white-painted, wooden Stevenson screen that opens to the south etc. etc.) It is temperature under those conditions that has ‘increased’.

      Changing thermometers should make no difference; except it has.

      The effect of rainfall on temperature is constant – lines are parallel.

      The offset (difference between intercepts) is a measure of the thermometer effect, and can be stated as: at the same level of rainfall, AWS probes estimate x.y degrees higher than thermometers. Confidence bands can be calculated.

      Importantly, residuals from the analysis, which are temperatures simultaneously adjusted for step-changes and rainfall, show no time-trend.

      The analysis has taken account of dry years during the recent drought (which ended ~2010) which were also warm; and changed instruments in 1996, which are biased-high.

      Thanks for your interest.

      Cheers,

      Bill

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  • #
    Peter Azlac

    Bill says

    “Remember here in OZ, 3 things are operating together: the PRT; small Stevenson screens and accurate high-frequency measurements (1 Hz, reported accuracy better than 0,01 deg.C.).

    The Bureau designed its PRT, they are manufactured locally and calibrated by the Bureau both in their lab and in the paddock by their staff.”

    The Lin and Hubbard study I quoted earlier evaluated three different electronic temperature sensors in use in the USA. They include the PRT units in use in the USCRN about which Lin and Hubbard conclude:

    There is evidence of data spikes, but that does not necessarily implicate the PRT (could be the screen for instance).

    “For the temperature sensor in the U.S. Climate Reference Networks (USCRN), the error was found to be 0.2 C to 0.33 C over the range -25C to +50 C. The
    results presented here are applicable when data from these sensors are applied to climate studies and should be considered in determining air temperature data continuity and climate data adjustment models.”

    These errors exclude those from siting, microclimate etc.

    00

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    Marinus

    Would it be possible to determine a standard correction between LIG and digital thermometers and to apply this correction to the old readings?

    10