JoNova

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The mysterious sudden jump in Melbourne temperatures in 1996 with an instrument change

Here’s a strange change. After 160 years of fairly constant maximum temperatures, the raw Melbourne records take a sudden step up by 0.7 0C in 1996. Coincidentally (or not) that is the same year that the automatic gauge was installed. The new electronic equipment is much more responsive to short peaks and dips compared to thermometers. Could the step up be due to the better resolution? It’s by no means definitive — these are yearly averages, not monthly, and it may be a real climate shift and not due to the equipment. The obvious question is whether this sort of jump occurs in other stations where AWS (automatic weather stations) were installed. That would have profound implications if it did, but surely it would have been noticed already? Melbourne is known for having “four seasons in one day”, so perhaps there is a small effect in most places, but the switchable peaks of of Melbourne summers make a larger difference. In any case, thanks to Tom Quirk (and Bill Johnston)  we have another puzzle in need of an answer. These AWS’s were installed all over Australia in the late nineties. If there was some effect, then there would be a lot of artificial small step ups as better equipment started to detect faster, shorter peaks. The ACORN adjustments make no corrections to the max record in 1996 but there is an adjustment made to the minima then. Hmm. – Jo

Twenty-first century Melbourne temperatures

Guest Post by Tom Quirk

During the 1990s the Bureau of Meteorology (BOM) started to install automatic weather stations. The minimum and maximum temperatures along with temperature readings every 30 minutes were recorded electronically. The weather stations used thermistors rather than mercury or alcohol thermometers for temperature measurements. Thermistors are electrical resistors that are very sensitive to temperature changes.

The Melbourne annual maximum temperature readings are shown in Figure 1. There is an unusual feature in the record as shown occurring in 1996. It is a break with a difference of 0.7 0C. The two straight lines are a best fit to the measurements and the difference is calculated from the lines at 1996.

Figure 1: Annual average raw maximum temperatures for the Melbourne Regional Office. The straight lines represent the best fit for two lines.

The ACORN-SAT adjustment record (Figure 2) shows only an increase of 0.41 0C to the maximum temperature record starting at 1 Jan 1990. This adjustment is explained as “statistical”. Interestingly the adjustment record shows a break in 1996 for the minimum temperature record.

Figure 2: ACORN-SAT adjustments to the raw Melbourne temperature measurements as listed by BOM.


There is reason to believe that the BOM started using the automatic weather station readings in 1996 rather than the thermometer measurements.  If the weather station thermistors have a faster response time to temperature changes then short term increases may be recorded. This would be particularly the case for summer in Melbourne where hot north winds and cool changes produce rapid temperature variations and the Melbourne Regional Office site is shielded in part by large buildings to the south but more open to the north with the gardens surrounding the Exhibition Buildings.

There is evidence of this faster response time with a larger temperature break in summer than in winter. Summer is the months of December, January and February and winter is June, July and August. The maximum temperatures are shown in Figure 3. Simple temperature differences before and after 1996 are given in Table 1 and show the increased difference in the summer.

Figure 3: Summer (Dec, Jan, Feb) and winter (Jun, Jul, Aug) average raw maximum temperatures for the Melbourne Regional Office. The straight lines represent the best fit for two lines with a break in 1999


Table 1: Average temperatures before and after 1996

Temperature 0C

1997-2013

1980-1996

Difference

Annual

20.98 ± 0.09

20.01 ± 0.12

0.98 ± 0.15

Summer

26.51 ± 0.23

25.16 ± 0.29

1.35 ± 0.37

Winter

15.27 ± 0.12

14.58 ± 0.11

0.69 ± 0.16

 

Conclusion

The break in the maximum temperatures in Melbourne in 1996 has not been detected in the BOM ACORN-SAT analysis. The break may be due to the shorter response time of thermistors compared to mercury thermometers. This would put the reason for the break on a better footing than a “statistical” explanation…

It would be interesting to know if other BOM sites have the same performance. But perhaps it is due to the peculiarities of the Melbourne location of the weather station. This follows Mark Twains sensible statement that climate is what you want and weather is what you get.

 

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153 comments to The mysterious sudden jump in Melbourne temperatures in 1996 with an instrument change

  • #
    Ross

    If you go to Google street view in La Trobe st. opposite the
    weather station and look to the south east you will
    see a massive newish building on the other side of the street .
    One suspects that reflected energy may be a factor .

    Again using Google street view you can also see glass fronted
    sky scrappers visible from the weather station which may
    reflect energy at certain times of the year .

    I am however uncertain exactly when the new buildings were constructed .
    Perhaps others can advise .

    Ross

    80

    • #

      Latrobe St site is grossly unsuitable. The heat from traffic waiting at the lights can be felt standing next to the fence around the enclosure; so it has to be measurable.

      Moreover, shielding of winds from the bay by more and more high-rise buildings; as well as their night-time radiation of stored heat frustrates any sensible measurements to compare with those obtained historically. Taller buildings, espe. those with orientations West and East, warm later/earlier under the setting/rising sun; effectively increasing the surface area in their proximity (“stealing” insolation from the larger, shaded areas).

      I was told a while ago that BoM officially stopped using the site (086071) for climate data a while ago but the station is still active as per its meta-data (PDF). There’s a note on each page of that document:

      Historical metadata for this site has not been quality controlled for accuracy and completeness. Data other than current station information,
      particularly earlier than 1998, should be considered accordingly. Information may not be complete, as backfilling of historical data is incomplete.

      It may astonish that although a minimum air temperature thermometer was installed in 1908, that such temperatures weren’t “recorded” until 1955. At least according to the meta-data.

      The site sketches in the meta-data also indicate a substantial increase in surrounding trees, even within the enclosure.

      110

      • #

        P.S. Forgot to mention the move to Olympic Park; a well-irrigated location. :-( It just gets worse, and worse.

        110

        • #
          Philip Shehan

          Bernard, Why the “It just gets worse and worse”?

          It is unreasonable to expect locations and technology of weather sations to never change, as much as this creates difficulties for historical comparisons, which is not the primary function of weather stations.

          This is precisely why historical data bases are adjusted. Giss adjusts specifically (as does Hadcrut)for such alterations, which cause both to reduce more recent temperatures due to the urban heat island effect. Some kind of scheming double bluff by the warmist alarmists not doubt.

          Then we get people like Giss abusing anyone who dares use these sources for historical temperatures. Except when they are used by Ross McKitrick, when they get the tick of approval.

          So yes some adjustment will need to be made to remove the 1996 step for historical comparisons.

          This will not change the fact that the warming trend slope from 1996 to the present is greater than that from 1910 to 1996.

          14

          • #
            Philip Shehan

            By the way I agree with Tom Quirk:

            The break may be due to the shorter response time of thermistors compared to mercury thermometers. This would put the reason for the break on a better footing than a “statistical” explanation…

            An established cause and effect relationship is always better than a statistical explanation, which is what you have when you don’t know what is causing the anomaly.

            33

            • #
              KinkyKeith

              Hi Phil, do you mind if I call you Phil?

              You may be right when you say that “The break may be due to the shorter response time of thermistors compared to mercury thermometers”, but there is another possibility which was mentioned on Skeptical Science yesterday which you may have missed.

              It seems that the lower woofoo valve on the screen door of the measuring unit may have been malfunctioning in its job of to stopping the screen door banging against the equipment when it is opened. This valve/piston is primed with CO2 gas and it is believed to have leaked out past the sensors. As we all know any increase in CO2 leads to increased air temperature so this may explain occasional irregularities.

              The problem is being fixed by filling the piston with argon and adding better seals.

              Hope this helps.

              KK

              51

              • #
                Philip Shehan

                KK.

                I did not say it, the guest author here did.

                But thank you for your thoughts on the subject.

                Please check that you took your medication this morning.

                16

              • #
                KinkyKeith

                Thanks Phillip,

                It seems you do mind me calling you Phil.

                As a seasoned intruder onto this website I thought you might have been a little more magnanimous.

                All this huffing and puffing over data sets which can have NO SCIENTIFIC MEANING when they are meshed/homogenised with data from “equivalent” recordings when conditions or locations change is a great tragedy for science.

                Even a temperature data set which has been harvested from just one point on earth tells us one thing: what happened ONLY at that one point.

                From a science or engineering perspective there is almost nothing which can be learned from that data set because the factors involved in the creation of those temperatures are so flukey.

                Having many thousands of such data sets for other locations does not add to the scientific rigor and only adds to the pointlessness of the whole data set charade.

                Whether the woofoo valve did it I don’t really know but it’s time we stopped wasting public money on this brainless tragedy of CAGW.

                KK

                71

              • #
                Heywood

                Oh Dear. I came here to read the Jo Nova blog, but seem to have stumbled on the Philip Shehan blog by mistake. My bad.

                60

            • #
              Philip Shehan

              No KK. I don’t mind you calling me Phil. Most people call me Phil and that is how I usually introduce myself. I hope you don’t min me abbreviating your name. Were you Christened Kinky Kieth or is that just what your family and friends call you?

              It’s just that your post was ridiculous.

              I mean why would anyone use an expensive gas like argon on their woofoo valve piston when a much cheaper alternative would be plain old nitrogen? Of course the seals are a problem. We always covered them with a bucket when filling our cryomagnet with liquid helium.

              This is not as ridiculous as your complaint that temperature data from thousands of sites all over the world tell us nothing about global temperature.

              “Intruder.” Gosh. Yes I know it must be distressing to many “skeptics” to come on a site where they hope they can give their views and indulge in rounds of mutual back slapping and congratulations on their insights with like minded souls without fear of contradiction to actually find someone putting a view they don’t like.

              13

              • #
                KinkyKeith

                Phil,

                I have seen countless pages of your comment but must admit I have read few of the later ones.

                After a while I found that I could not find a core to any or your work.

                Mostly it was just ad hoc “comment” in response to another comment on a previous comment by someone else.

                While it’s good to know you are aware that Argon is not useful in pistons and tyres because of cost, that really doesn’t give

                any of us here any more information which might help us see Man Made Global Warming as a scientific reality, indeed we see

                most of your comments as adding to the confusion which helps the warmer enthusiasts keep the peasants ignorant and in line.

                Personally I see the whole issue of data meshing and homogenisation of past records as a gigantic yawn because it is basically irrelevant. It does however serve a political purpose and I suspect that that is the main purpose anyhow.

                The impartive of orbital mechanics overshadows the relevance of homogenised data.

                It’s so easy: 25,000 years ago the Northern hemisphere was under massive ice fields with New York being under a field 1.5 km deep.

                Then the Earths orbit changed wrt the Sun and it all (mostly) melted and seas rose 125 metres.

                The cycle will happen again but the time scale allows warmers a lot of time to perfect the scam.

                KK

                41

              • #
                Philip Shehan

                KK

                The “core” to my work is to comment on scientific claims here.

                As I said it is not to join in the mutual back slapping and congratulations on all of us here being so right and those warmists being so wrong.

                The subject here is weather stations, and my initial post to Bernard above was with regard to this.

                Then as usual I get a number of comments, which I reply to which generates more comments.

                So yes there does tend to be a chain formed which often meander off the original topic. Somehow we to have gotten on to woofoo valves.

                “While it’s good to know you are aware that Argon is not useful in pistons and tyres because of cost, that really doesn’t give any of us here any more information which might help us see Man Made Global Warming as a scientific reality..”

                KK, you brought up the subject of woofoo valve pistons. I thought it not quite relevant myself.

                “most of your comments as adding to the confusion”

                Yes, as I noted above, so many “skeptics” find the confusion resulting from having their opinions being challenged very unsettling.

                You are correct that orbital parameters were responsible for large scale climate change in the past. And if and when such a change occurs some millenia down the track, we may need reserves of fossil fuels to warm the planet,if we have not burned them all.

                But at the moment, the problem is not long term orbital cycles, but a rapid rise in temperature due to burning fossil fuels.

                14

              • #
                Rereke Whakaaro

                Most of us here start from the null hypothesis, which is that temperatures are naturally variable between natural limits, depending on latitude, and natural cyclic patterns.

                It is then beholding on the Climatologists, and Meteorologists, and Atmospheric Physicists, to demonstrate, through repeatable observation or empirical experimentation, that any and all variation from the null hypothesis is caused by some external agent, which is in turn caused by anthropogenic activity, which can repeatably demonstrate the chemical and physical means whereby that occurs.

                So far, over many comments here, you have failed to disprove the null hypothesis.

                Oh yes, I did intend to use the word “natural” three times, in the first paragraph, since it is seen so rarely in the Climate Change literature.

                100

              • #
                Philip Shehan

                Rereke,

                DEFINITION OF ‘NULL HYPOTHESIS’
                A type of hypothesis used in statistics that proposes that no statistical significance exists in a set of given observations. The null hypothesis attempts to show that no variation exists between variables, or that a single variable is no different than zero. It is presumed to be true until statistical evidence nullifies it for an alternative hypothesis.

                http://www.investopedia.com/terms/n/null_hypothesis.asp

                This is why I keep talking about statistical significance, and have shown that warming passes the statistical significance test, whereas the pause does not.

                “Oh yes, I did intend to use the word “natural” three times, in the first paragraph, since it is seen so rarely in the Climate Change literature.”

                I don’t know what literature you have been reading but the most recent IPCC report talks about it over and over again, as have I in many of my posts.

                In particular in reply to those who insist that the failure of warming to follow CO2 concentration exactly means that CO2 does not cause warming.

                But actually the correlation is pretty good, the contributions from natural forcings notwithstanding.

                http://tinyurl.com/njthcd9

                Note however that the 15 year and 20 year trends are not statistically significant for warming, or a pause, whereas the 35 year trend does. As Silliguy reminded me, short term trends (less than about 2 decades) rarely pass the statistical significance test as the noise dominates the signal.

                Trend: 0.147 ±0.210 °C/decade (2σ)

                Trend: 0.141 ±0.155 °C/decade (2σ)

                Trend: 0.138 ±0.070 °C/decade (2σ)

                13

              • #
                KinkyKeith

                RW that is a very apt comment.

                I naturally congratulate you.

                KK

                20

              • #
                the Griss

                Since 2001, there has been a central trend of close to zero in all temperature data bases.

                A zero trend can be taken back 19 years in Hadcrut4, 16 years in UAH, and a whopping 26 years in RSS before it becomes “statistically” unsupported.

                41

              • #
                KinkyKeith

                Phil says:

                “Of course the seals are a problem. We always covered them with a bucket when filling our cryomagnet with liquid helium.”

                It is really great that you have a job as a lab technician but I feel that you might be better able to analyze all of the

                factors involved in Global Warming if you did a degree with lots of maths, Physics, Chemistry plus some Geology and a few

                years of modeling such as might be found in a Chemical Engineering Degree.

                Even then the lack of course work in Mass, Heat and Momentum transfer which is highly relevant to this situation may still leave you struggling to put it all together.

                All the best anyhow.

                KK

                31

              • #
                Philip Shehan

                G,

                “A zero trend can be taken back 19 years in Hadcrut4, 16 years in UAH, and a whopping 26 years in RSS before it becomes “statistically” unsupported.”

                Here are your 16, 19 and 26 year “zero trends” which McKitrick gives slopes and error margins of 0.0609, with 95% error margins between cooling of 0.0586 and warming of 0.1084 C/decade, 0.9025 with error margins between 0.0063 and warming of 0.1093 C/decade, and 0.1184, between cooling of 0.0005 and warming of 0.20373 C/decade.

                http://www.woodfortrees.org/plot/hadcrut4gl/from:1914/to:2014.25/mean:12/plot/hadcrut4gl/from:1995/to:2014.25/trend/mean:1/plot/uah/mean:12/plot/uah/from:1998/to:2014.5/trend/plot/rss/mean:12/plot/rss/from:1988/to:2014.25/trend

                You have yet another chance to explain how the error margins for the 16, 19 and 26 year periods constitute a statistically significant pause.

                http://joannenova.com.au/2014/09/manns-trick-to-hide-the-decline-still-shocking/#comment-1575093

                03

              • #
                the Griss

                Its all there in Ross’s paper, all you have to do is read it and UNDERSTAND it !!

                If you can’t do that, I can’t help you. Sorry.. Your problem not mine.

                31

              • #
                James Murphy

                So, Phil, or Philip, or indeed, Mr Shehan, just out of interest, what’s your opinion of blogs which indulge in mutual back-slapping, but are not, to use your phrase, ‘skeptical’, such as that which is (I assume) ironically named ‘skeptical science’?

                I don’t think anyone here actually minds a reasonable discussion with reasonable people, at least that has been my impression. (‘reasonable people’ do not have to agree with the ‘skeptical’ stance, but being able to display some modicum of brain activity and being able to contribute something more than insults is an obvious advantage, as I am sure you would agree).

                51

              • #
                the Griss

                And STILL continuing to add in the meaningless pre-1979 Had series, just because it makes the trend lines at the end look “oh so steep”

                That is the sort of thing a child-minded propagandist would continue to do…. NOT a scientist.

                31

              • #
                the Griss

                I find it quite bizarre that someone who “tells us” that he understands basic statistics cannot comprehend Ross’s paper.

                And even more bizarre that that person is unable to verify Ross’s result using the SkS trend calculator he is wedded to.

                When I first read Ross’s paper, the 26 years in RSS surprised me, but it took about 20 seconds to verify its correctness in the SkS trend widget.

                I’m sorry for you that you don’t appear to have that capability.

                I seem to have greatly overestimated your ability.

                22

              • #
                Rereke Whakaaro

                Yes, Griss,

                I set a little trap for Mr Shenan; one that was quite subtle I thought, and he blithely walked into it.

                He doesn’t actually understand atmospheric physics. He is a talking head, and working from a script. He is good at working from the script, and I suspect he has computer assistance. Sort of being a wetware interface for a software response bot.

                KK has seen the same thing, in pointing out that Mr Shenan seems to have a lab-tech’s level of knowledge, and probably a lab-tech’s grasp of what models are, how they actually work, what they are capable off, and more to the point, what they are not capable off.

                51

              • #
                Rereke Whakaaro

                Philip Shenan @ 1.1.1.1.4

                I don’t accept your answer, because you have relied on the narrow definition of “null hypothesis” used in statistics, and not on the more general definition that I included in my original comment 1.1.1.1.3, even paying you the courtesy of expressing it in terms more relative to climate change.

                Would you like to have another go, now that you know I set a trap. Is your level of science up to the task?

                50

              • #
                Philip Shehan

                G, NO it is not in Ross’s paper, but you would not know because you do not understand it.

                At the risk of repeating myself in my reply to Heywood:

                Griss, for the n+1th time has failed to give an explanation for this problem. Ross has not explained this in the paper, as G claims. Ross has confused a time period no longer showing statistically significant warming since there is a miniscule dip into the cooling region and a huge upper warming margin and a large warming trend line as statistically significant pause.

                This is totally incorrect.

                Not a single person on this blog has been able to show, or even put an argument, as to where my assessment of this error is wrong, nor for that matter has McKitrick.

                02

              • #
                Philip Shehan

                Rereke,

                How utterly , utterly , utterly TYPICAL of “skeptic” argument.

                Reject a term or data or paper or author or anything that does not support your prejudice.

                12

              • #
                Philip Shehan

                And Oh yes Rereke you are so clever. (As with your remarks on scientific “papers” which demonstrate you do not understand the very real distinctions in scientific publishing.)

                You carefully laid a trap which you knew I would walk into. Oh please.

                You simply were not expecting a reply that would so effectively challenge your comment, then in addition to simply demanding I adhere to your definition of null hypothesis, as a typical “skeptic”, you attach a series of false, evidence free ad hominem put downs in a pathetic attempt to somehow back up your argument.

                What for instance is KK’s evidence that I have a technician’s level of knowledge?

                In reply to KK’s joke comment, I made couple of joke replies, including one which drew this response from KK:

                “Of course the seals are a problem. We always covered them with a bucket when filling our cryomagnet with liquid helium.”

                It is really great that you have a job as a lab technician …

                In fact at this stage I was taking an example from real life.

                The cryomagnets in Nuclear Magnetic Resonance spectroscopy have to be filled with liquid helium every few months.

                Now apart from the fact that universities are so strapped for cash these days, there are not that many technicians, a helium fill is a tricky process, with the possibility of a magnet “quench” wrecking a magnet worth hundreds of thousands of dollars and leaving us all twiddling our thumbs for several months until a replacement arrives from Germany. So we preferred to do it ourselves.

                My scientific credentials and understanding of models is demonstrated in the following publication.

                http://adsabs.harvard.edu/abs/1985JMagR..63..343S

                Abstract

                The use of a specifically constructed probe having a transverse solenoid coil operating at 13 MHz has permitted convenient detection of 95Mo resonances in solutions of [Mo] = 5 × 10 3¯M for compounds whose linewidths, W {1}/{2}, are in excess of 1000 Hz. Application of a three-pulse sequence, 90° +x (acq) +-180° x-τ-90° -x (acq) + and shielding of the coil with lead substantially reduces ring-down times. A series of binuclear molybdenum(II) species which feature formal Mo-Mo quadruple bonds were examined. 95Mo resonances were detected in the range 3227-4148 ppm and this is the most deshielded class of molybdenum compounds so far discovered. Observed linewidths covered the range 200-1500 Hz. Those for the compounds [MO 2(O 2CR) 4] could be rationalized on the basis of quadrupolar relaxation and the Hu-Zwanzig model of molecular motion.

                Suck on it.

                12

              • #
                the Griss

                YAWN.. your ignorance is getting VERY boring !!

                11

              • #
                the Griss

                And no P. People have realise you cannot be taught.

                They just can’t be BOTHERED any more. !!

                You have worn them down with your stupidity and ignorance !!

                Well done !! :-)

                11

              • #
                Philip Shehan

                James,

                I do indeed agree with the second part of your statement here (italicised), but definitely not the first:

                “I don’t think anyone here actually minds a reasonable discussion with reasonable people, at least that has been my impression. (‘reasonable people’ do not have to agree with the ‘skeptical’ stance, but being able to display some modicum of brain activity and being able to contribute something more than insults is an obvious advantage, as I am sure you would agree).”

                As for Skeptical Science, again I note that people who call themselves “skeptics” and who show no real skepticism whatsoever think they have a copyright on the word. Under the name Skeptical Science is written:

                Getting skeptical about global warming skepticism.

                In spite of the claims here, I don’t visit SKS on even a weekly basis, except when some discussion comes up where it is particularly relevant (see below) although I frequently use the trend calculator (which Griss has recently affirmed its accuracy, as it backs McK’s results but will continue to abuse me for using it) and a couple of useful graphs, the provenance of which I have verified.

                I do sometimes go there for summaries of counterarguments for skeptic claims, as well as other internet sources, but always check the cited primary sources. I don’t think I have ever referenced SkS itself as opposed to the primary literature sources referenced there after I have checked them.

                SkS is not primarily a controversy of the week blog where people go and agree or disagree with little or no actual analysis. It is a reference source on the various arguments and its entries are classified by topic for that purpose.

                The comments are very knowledgeable and technical and ad hominem and off topic comments removed. Some of mine have been removed on this basis.

                Take a look at the comments here, where having no luck in getting any “skeptic” or McKitrick himself to answer my questions on his paper, I asked if anyone over there had any opinion.

                My comment is at #24.

                http://www.skepticalscience.com/2014-SkS-Weekly-Digest_36.html#comments

                02

              • #
                the Griss

                [SNIP Griss, inflamatory. - Jo]

                11

              • #
                Philip Shehan

                PS James, Take a look at the moderator’s comment at #4 in response to comments that are utterly tepid compared to those found here:

                Moderator Response:
                [JH] You are already skating on the thin ice of sloganeering which is prohibited by the SkS Comments Policy.

                Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

                Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

                02

              • #
                Philip Shehan

                Thank you G for supplying a perfect example of why I disagree with the first part of James’ statement.

                02

              • #
                Philip Shehan

                Pardon me, the link to my paper above does not work.

                Here is another:

                http://www.sciencedirect.com/science/article/pii/0022236485903257

                02

              • #
                Philip Shehan

                I withdraw any aspersions on the competence of our technicians in my above comment (where the budget allowed them). In some places we did indeed have technicians available and who participated. But a helium fill is at least a two person operation.

                02

              • #
                Philip Shehan

                Now if anyone here really needs any further evidence of the depths of G’s stupidity, Here it is:

                “I find it quite bizarre that someone who “tells us” that he understands basic statistics cannot comprehend Ross’s paper.

                And even more bizarre that that person is unable to verify Ross’s result using the SkS trend calculator he is wedded to.

                When I first read Ross’s paper, the 26 years in RSS surprised me, but it took about 20 seconds to verify its correctness in the SkS trend widget.”

                Now never mind that G has abused me up hill and down dale for using “the SkS calculator”. Here he as used it to verify the correctnmess of Ross’s data. So it is Kosher after all.

                Now as for the claim

                “And even more bizarre that that person is unable to verify Ross’s result using the SkS trend calculator he is wedded to.”

                My very first detailed analysis of McK’s paper did exactly that (I refer to the SkS calculator as Cowtan’s algorithm):

                http://joannenova.com.au/2014/09/the-mann-with-no-friends/#comment-1569062

                And its not as if G missed it for his reply is directly below:

                “ROFLMAO.. what a load of meaningless waffle. Phillip. !!

                You really have outdone yourself in the tiresome stupidity stakes this time…”

                You see people, you see the kind of stupidity I have to deal with from this knucklehead?

                02

          • #

            This will not change the fact that the warming trend slope from 1996 to the present is greater than that from 1910 to 1996.

            Philip
            You mean this slope right?
            http://www.woodfortrees.org/plot/hadcrut3sh/from:1996/plot/hadcrut3sh/from:1996/trend
            So it is supposed to be greater than this one?
            http://www.woodfortrees.org/plot/hadcrut3sh/from:1910/to:1996/plot/hadcrut3sh/from:1910/to:1996/trend

            20

            • #
            • #
              Philip Shehan

              Siliggy, No I meant the slope for Melbourne data being discussed here.

              Southern Hemisphere data is of course mostly ocean data.

              Hadcrut3, which did not have adequate data from higher latitudes, has been superseded by Hadcrut 4:

              I have plotted pre and post 1996 data for the northern and southern hemispheres here.

              http://www.woodfortrees.org/plot/hadcrut4sh/from:1996/trend/plot/hadcrut4sh/from:1910/plot/hadcrut4sh/from:1910/to:1996/trend/plot/hadcrut4nh/from

              05

              • #
              • #

                So your point is about the rate of warming over a shorter period meaning something.
                This then is just as valid but on a global scale and against not with UHI.
                http://www.woodfortrees.org/plot/hadcrut4gl/from:1908/to:1943/trend/plot/hadcrut4gl/from:1908/trend

                30

              • #
                Philip Shehan

                Actually no Silligy I doubt that there is any statistical difference between pre and post 1996 trend lines.

                But nobody here seems to care about statistical significance, unless Phil Jones has “admitted” that there has been no statistical significant warming for 15 years, and then they don’t understand it, but heck, skeptic blogs are using it to beat Jones with so let’s all pile on.

                I was curious to see if anyone would pick me up on that. (Note that I did not simply write “trend” but the “slope of the trend lines”, excluding the error margins.)

                Although you have not specifically used the magic words “statistical significance” you have mentioned short time periods which is why Jones’ remark about a 15 year period was utterly unremarkable, so kudos to you.

                13

              • #
                Philip Shehan

                G,

                Yes I noticed your post on this the other day so I wandered over to the blog to check.

                Firstly, it is not as you and the blog claim a “paper.”

                A paper would contain original research and be peer reviewed before publication.

                The item is “correspondence” or a letter to the editor, commenting on a peer reviewed and published paper.

                I also proceeded to the journal website and noted that the authors of the original paper had been afforded the right of reply to the correspondence, immediately following it:

                Spatiotemporal patterns of warming
                Marc Macias-Fauria, Alistair W. R. Seddon, David Benz, Peter R. Long & Kathy Willis
                See also: Correspondence by Zhaohua Wu et al.

                Reply to ‘Spatiotemporal patterns of warming’
                Zhaohua Wu, Eric P. Chassignet, Fei Ji & Jianping Huang
                See also: Correspondence by Marc Macias-Fauria et al.

                The reply begins:

                Wu et al. reply —

                Macias-Fauria et al.1 highlight deficiencies in the high-resolution gridded climate database2, 3 prepared by the Climate Research Unit (CRU). In our analysis4, yearly averaged land surface air temperature (SAT) at each grid from this database was decomposed using the multidimensional ensemble empirical mode decomposition5, 6, 7,…

                But the rest is paywalled.

                So I went to the comments section of the blog. Mine was the first submitted, and requested that the blogmeister, who had managed to publish the first piece of correspondence, could also put up the authors’ response.

                Neither the response or my request that it be supplied have yet been posted.

                Anyway, the complaint is about the accuracy of temperature data when comparing regional data to determine when (not if) warming in different regions began.

                Specifically that the data from early parts of the record in the polar and tropical regions are too few and the uncertainties too high to justify the conclusions. (The trouble is, in comparisons of data sets with uncertainties, the uncertainties must be added.)

                Well in the absence of the authors reply that may or may not be so.

                But how uncertain is the global Hadcrut data, which like Giss and NOAA uses Global Historical Climatology Network Monthly data set (GHCN-M).

                The Berkely Earth surface temperature study was undertaken:

                http://berkeleyearth.org/about-data-set

                The Berkeley Earth Surface Temperature Study has created a preliminary merged data set by combining 1.6 billion temperature reports from 16 preexisting data archives. Whenever possible, we have used raw data rather than previously homogenized or edited data. After eliminating duplicate records, the current archive contains over 39,000 unique stations. This is roughly five times the 7,280 stations found in the Global Historical Climatology Network Monthly data set (GHCN-M) that has served as the focus of many climate studies.

                The results indicate that the temperature profiles match those of the GHCN-M based global data sets, and that uncertainties are acceptable for the period 1850 to the present which the GHCN-M based data sets cover.

                BEST has pushed back to 1750, but the uncertainties become very large.

                http://berkeleyearth.org/summary-of-findings

                02

          • #
            Rereke Whakaaro

            … expect locations and technology of weather sations [sic] to never change, as much as this creates difficulties for historical comparisons, which is not the primary function of weather stations.

            For once, you have said something sensible Philip.

            I have some experience with weather stations located at airfields. The purpose of those stations is to measure the temperature, humidity, and wind speed and direction, at the end(s) of the runway(s). This sort of information is kind of critical for takeoff and landing purposes. Especially with jet aircraft, which are only marginally stable during takeoff and landing.

            They [the weather stations] suffer from a lot of heat island effect, which is actually the point of where they are sited.

            Can you explain a) why there was a preponderance of these stations used in the original climate modelling process, and b) why, when they were removed because of complaints from people, such as myself, the resulting adjusted area temperatures actually increased?

            20

            • #
              Philip Shehan

              Rereke, I am not sure that such stations do constituted a preponderance of those used.

              I recall that Watts had a project going to identify suspect weather stations sites. When they had been so identified, they were removed from the data, but there was essentially no difference.

              02

              • #
                Rereke Whakaaro

                Yes, I am aware of the Watts project, and you highlight the problem exposed by it.

                Jet exhaust is several hundreds of degrees Celsus, and it gets well mixed with the air over airfields due to the ground turbulence caused by aircraft movements, take offs, and landings, not to mention the prevailing wind. They should never have been used, but they were.

                Then, as you say, they were removed from the data. But that removal made no difference. Really? How do you explain that? If the models are really based on the data, and if the data included the airfield readings (as we observed in the published list of sites), then the impact of those airfield sites must surely have had some impact on the overall results. I have known airport temperatures to be more than ten degrees higher than the surrounding area, and yet you claim that their removal was insignificant? How come?

                30

              • #
                Philip Shehan

                Rereke,

                I don’t know how many weather stations are sited at airports and how many of those were subjected to jet blasts as opposed to sited among bushes behind the toilet block etc but I think it is probably a small proportion of the 7,280 stations found in the Global Historical Climatology Network Monthly data set (GHCN-M)on which Giss Hadcrut and NOAA and others are based, and a still smaller proportion over 39,000 unique stations used by the Berkely Earth Surface Temperature (BEST) study.

                One of the papers which studied the effects of eliminating the sites nominated by Watts, has Watts as a coauthor. And it does indeed conclude that the better sited stations actually measure warmer values than poorly sited stations (page 13):

                [65] Overall, this study demonstrates that station exposure
                does impact USHCNv2 temperatures. The temperatures
                themselves are warmest compared to independent analyses
                at the stations with the worst siting characteristics.

                http://pielkeclimatesci.files.wordpress.com/2011/07/r-367.pdf

                http://www1.ncdc.noaa.gov/pub/data/ushcn/v2/monthly/menne-etal2010.pdf

                I know skeptics tend to reject out of hand any evidence that goes against their prejudices, but unless you can come up with a specific objection to the results of these papers…

                Or perhaps write to Watts and ask him. It is after all his paper.

                00

          • #
            the Griss

            Again, Ross has not used the pre-1979 Hadcrut data for anything but a basic illustration of changes of slope and a simple illustration of how the method works on a longer data set.

            He has not attempted to glean anything meaningful out of it.

            Your continuation on this point is TRULY SAD and PATHETIC !!!

            11

            • #
              Philip Shehan

              G, He used it, so he must think it OK.

              And why the date 1979?

              Is it because the satellite data confirm the other data sets Giss Hadcrut and NOAA after this?

              So on what basis do you assert that the pre-1979 data must be wrong?

              See also my comment above on the BEST data set.

              33

              • #
                the Griss

                The satellites bought the manipulations of Jones,Hansen and NOAA at least into some sort of control.
                (although they still “manipulate” if they think they can get away with it.)

                I know that you are a guy who has to use corrupted and manipulated data to make his point
                (its part of your “science”, and probably always has been)

                Best? roflmao.. run but Muller’s daughter.. as rabid warmist.. trust if you want to your choice as a once-was !!!

                And they had to hire Mosher as a mouthpiece.. how funny is that !!! :-)

                And why 1979? it just happens to be the date reasonably unmanipulated data became available… but what would you know about that. !

                Try comparing early Hansen graphs with his graphs after he ‘evangelised’. (I wish we could see his bank account around that time)

                So Philly/BA5, you just keep using that data that you KNOW to be highly suspect… its what you do… it who you are.

                22

              • #
                the Griss

                Just imagine what the Giss and Had temperature would be now if the satellite data wasn’t available. !!!!!!!!!!!!!!!!!!

                ….we would all be absolutely ROASTING !!

                As it is, the nice, steady, nothing happening, minor natural variation, climate continues.

                As it has for the last 100 or so years.

                (thanks goodness for a small amount of warming from the LIA)

                Enjoy it while it lasts, and buy some more blankets.

                22

              • #
                the Griss

                Just think of it Phillip, if it weren’t for natural global warming…

                Melbourne’s winter temps would be like Canberra’s ! :-)

                32

              • #
                Philip Shehan

                Griss, if I was of a litigious nature, you and Ms Nova may have been in serious trouble for the above remark which is a serious and actionable attack on my professional reputation.

                Remember, I have had successful legal experience in the past, and I find it most enjoyable.

                I hereby waive any right to sue, but merely request that you justify the statement.

                24

              • #
                the Griss

                You continually use pre-1979 Hadcrut/Giss..

                You know it is suspect, especially before 1950, as the peer-reviewed paper I linked to showed.

                Stop using it… no problem.

                THINK about the source of your data before you use it.. is it really viable, is it beyond reproach !!

                Then use it… or don’t…. your choice, your science.

                22

              • #
                the Griss

                And if your “reputation” is really that important to you….

                …. why do you troll like you do ?

                Very odd.

                Your reputation would stay intact.. if you didn’t repeatedly inhabit scientific blogs as a troll.

                Again… totally your decision.

                22

              • #
                Philip Shehan

                G,

                You have demonstrated over and over again that about the only argument you have is personal abuse, and rejecting any data you don’t like as bogus or any scientist who produces it as a corrupt warmist.

                This, according to you and so many here, makes you a “skeptic”.

                It makes you an ideological fanatic.

                As for being a troll, see my remark to KK on my “intruder” status.

                25

              • #
                the Griss

                “It makes you an ideological fanatic.”

                From you.. that is truly hilarious..

                Do you live in a house of mirrors? !

                22

              • #
                Heywood

                “Griss, if I was of a litigious nature, you and Ms Nova may have been in serious trouble “

                Actually as an aside, it would be interesting to know whether a blog alias can sue another blog alias.

                Neither use their real name and neither have had their true identity verified.

                It would be difficult to prove damage to reputation when you don’t actually know who you are talking to.

                11

              • #
                Philip Shehan

                Heywood,

                I use my real name here. So “the Griss” would be in trouble, the fact that he hides behind a screen name notwithstanding. If I used a screen name that would be another matter.

                But as you keep reminding people, it is very well known over at Bolt that I use the screen name Dr Brian or Brian S (that is the only place I use a screen name, and there was a specific and regrettable reason for it. That problem seems to have passed and I should probably use my real name over there as well, but I think I saw that they do not allow real names over there. Is that Correct.

                So you, having helped in establishing my real identity both there and here on multiple occassions, and alot of people took to calling me by those names here. It would be interesting as to how actionable an attack on “Dr Brian” or Brian S.

                This would not save him from being tracked down through his IP address. That is what subpoenas are for. I have personally served more than a few in my time, in spite of the recipients going to considerable trouble to avoid them.

                Anyway Heywoood good to see you back as i have not heard from you since you asked me if McKtrick had gotten back to me after you supplied his email address, apart from the fact that you complain above that I actually answer a lot of comments directed to me. I said no, and posted the content of my email to McK. You dissappeared from the discussion. There was a lot of discussion following on this.

                If you missed it, and can’t be bothered going back to the view he thread, a very brief summary of my criticism is to be found on this thread in a reply to “the Griss”

                http://joannenova.com.au/2014/09/the-mysterious-sudden-jump-in-melbourne-temperatures-in-1996-with-an-instrument-change/#comment-1577913

                Griss, for the n+1th time has failed to give an explanation for this problem. Ross has not explained this in the paper, as G claims. Ross has confused a time period no longer showing statistically significant warming since there is a miniscule dip into the cooling region and a huge upper warming margin and a large warming trend line as statistically significant pause.

                This is totally incorrect.

                Not a single person on this blog has been able to show, or even put an argument, as to where my assessment of this error is wrong, nor for that matter has McKitrick.

                So go ahead Heywood, be the first kid on the block to do so.

                01

              • #
                Heywood

                Brian,

                “You dissappeared from the discussion. There was a lot of discussion following on this.”

                Unlike you (it seems), I actually have a life away from blogs and the internet. On occasion I have time to pop in briefly. This is, after all, just a blog and not worthy of spending hours of my time responding to everyone that mentions my name. Feeling compelled to respond to each and every post could reveal and underlying obsessive compulsive disorder, and as I don’t feel that compulsion, I reckon I am pretty safe.

                If I get a chance, I’ll go back and have a read, but I am tipping that it doesn’t address my original criticism which wasn’t about your calculations at all, but more about the wisdom of using a blog that clearly doesn’t share your warmist bent to vent your spleen about McKitrick’s peer reviewed and published analysis of the temperature data, instead of doing the truly scientific and respond directly to the author or the journal that published the paper. I was also interested how a part time expert in nuclear resonance with a passing interest in statistics goes against a professor of economics who’s area of expertise is statistical analysis. Your calculations could be right, but until the man you are specifically criticising acknowledges it, I’ll remain agnostic.

                The other criticism I had was your claim that McKitrick was ‘cherry picking’ before you had even had a good look at the paper (by your own admission), but I see you have withdrawn that comment. Good for you.

                10

              • #
                Philip Shehan

                Well Heywood, that about sums you up.

                I do as you suggest and write to “the man” who does not get back to me.

                You say I should write to the journal.

                I have explained that my comments do not constitute original research and would not be peer reviewed anyway and even if they did decide to print a letter as “correspondence” that would not change things one iota.

                And although I have not mentioned this before, as I just wanted to concentrate on the content, but since you have brought up “authority” the publication is a pissant open journal of low standing and I don’t even know if they have a correspondence section.

                One wonders why McK had to go so far down market to get his paper published.

                Knocked back by the better journals would be my guess.

                You have been given the opportunity to comment on my objection, and you like everyone else here and McK himself has failed to even attempt to give a reason why it is wrong.

                That is how lacking you are in understanding the subject.

                Instead you fall back on an argument from authority.

                02

              • #
                Heywood

                And thus, the compulsion brings you back again.

                Funny as.

                10

            • #
              the Griss

              And do you mean REAL data?… or the highly dubious stuff that is the end product of BOM, Giss, and HadCrut manipulations and homogenisations.

              Do you really call what they put out “data”… really ????

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    • #

      …a massive newish building on the other side of the street.

      The reflections from buildings should show up at a time of day that corresponds to the position of the sun. This will shift one hour with daylight saving.
      Check this parabolic “Walkie Talkie” building.
      https://www.youtube.com/watch?v=hlRNO8xcrgU

      Bernd the daily data back to 1855 comes up here.
      http://www.bom.gov.au/climate/data/
      (086071)

      10

  • #
    thingadonta

    So instrument changes are ok as long as it gets warmer?.

    110

    • #
      Leigh

      “It has been said before. It will be said again. The adjustments always seem to add to global warming.”
      Anthony Watts

      60

      • #
        Tim

        I heard on radio news that 85% of billing errors from financial institutions were in the favour of the institution.

        Seems like the same formula is pretty popular with other institutions.

        70

      • #
        Philip Shehan

        Yes Leigh I am sure it’s been said before and will be said again, the fact that it is wrong notwithstanding.

        See my reply to Bernard above.

        15

        • #
          James Bradley

          Show why it is wrong, Phil.

          00

        • #
          Leigh

          Phil, so your a fan of world’s best practice of fiddling the numbers to make the planet appear warmer?
          Then extracting more of my tax dollars to again tell me I’m going to perish in the apocalypse that is catostropheric anthropological global warming.
          I might add, peer reviewed by expert fiddlers from around the world.
          Who do the same thing right around the world in tune in their combined effort to heat the planet.
          There is but one small problem.
          It’s not happening.

          00

      • #
        Philip Shehan

        James,

        http://pubs.giss.nasa.gov/docs/1999/1999_Hansen_etal_1.pdf

        See figure 3 for examples of adjustments for UHI.

        15

        • #
          Tanner

          Philip

          Figure 3 – The referenced graphs for the Rural stations near Tokyo and Phoenix show no significant warming trend for over 100 years but the graphs for Tokyo and Phoenix show a 2C and 3C warming trend (UHI effect?). The past temperatures for Tokyo and Phoenix have then been adjusted up “warmed” by 2C and 3C respectively to reduce the warming trend? Why is it that the past temperatures in the rural areas are acceptable to use but not in Tokyo or Phoenix. Surely it would have been better to adjust the current Tokyo and Phoenix temperatures down “cooled” to account for the UHI effect or to ignore them?

          Furthermore, the Anthony Watts quote from Leigh above “The adjustments always seem to add to global warming” is technically correct as past temperatures have been “warmed” and are now 2C and 3C warmer than the actual recorded historical temperatures in Tokyo and Phoenix even though the adjustment may have reduced the “warming” trend!

          Hansen concludes in the link provided “However, urban effects are nonnegligible, and studies of current climate trends need to pay
          close attention to station selection. We encourage research aimed at improved definition and removal
          of urban influences.”

          In full agreement with Hansen ;)

          20

          • #
            Philip Shehan

            Tanner. You have very much mistaken the point.

            Go back and look at figure 3. Adjusting the temperatures down to match the nearby rural stations is exactly what has been done.

            The city temperatures have been reduced to remove the increasing UHI as the cities grow.

            In any case it would not matter if all the earlier records were adjusted up since the amount of warming is determined by the relative changes in temperature from the past to the present.

            So the adjustment reduces the change in temperature over time whichever way you do it.

            So the statement “The adjustments always seem to add to global warming.” is wrong.

            Note that temperature graphs do not usually show the measured temperature on the vertical scale. They show the temperature anomaly, the change from an arbitrary reference point.

            That is the reason for the offset parameter in WFT plots when different data sets are being compared.

            With offset:

            http://www.woodfortrees.org/plot/hadcrut4gl/mean:12/offset:-0.26/plot/gistemp/mean:12/offset:-0.35/plot/hadcrut3vgl/mean:12/offset:-0.26/plot/rss/mean:12/offset:-0.1/plot/uah/mean:12

            Without offset:

            http://www.woodfortrees.org/plot/hadcrut4gl/mean:12/offset/plot/gistemp/mean:12/offset/plot/hadcrut3vgl/mean:12/offset/plot/rss/mean:12/offset/plot/uah/mean:12

            05

            • #
              Tanner

              Philip.

              To use your own words ;) You have very much mistaken the point.

              Go back and look at figure 3. Adjusting the temperatures down to match the nearby rural stations is exactly what has

              NOT

              been done.

              The “past” city temperatures have been

              INCREASED

              to remove the increasing UHI as the city grows.

              Tokyo – measured temperature 1880 = 13C
              Tokyo – adjusted temperature 1880 = 15C (adjusted UP 2C adjustment)

              Phoenix – measured temperature 1880 = 19.5C
              Phoenix – adjusted temperature 1880 = 22.5C (adjusted UP 3C)

              Tokyo – measured temperature 1998 = 16.5C
              Tokyo – adjusted temperature 1998 = 16.5C (no adjustment)

              So the City temperatures have not been REDUCED in any way whatsoever! I do understand exactly what the graphs are showing and am just commenting on the graphs that you provided a link to which shows that the historical temperatures were WARMED not COOLED!! I accept that this goes against the current trend of homogenizing the past temperatures by cooling them and thereby increasing the “warming” trend.

              The graph of the adjustments looks like the adjustments have been down “cooling the present” however it is a graph showing that the amount of adjustment to the historical temperature has reduced over time (smoke and mirrors)

              Read my comment above. I acknowledge that the adjustments would have reduced the warming trend however the adjustments have “warmed” the past and not “cooled” the present!! If the current temperatures had been adjusted down by 2C and 3C for UHI then the Earths current average temperature calculation would be lower than reported and hence my question.

              Why is it that the past temperatures in the rural areas are acceptable to use but not in Tokyo or Phoenix. Surely it would have been better to adjust the current Tokyo and Phoenix temperatures down “cooled” to account for the UHI effect or to ignore them?”

              40

              • #
                Rereke Whakaaro

                That is rather typical of Philip, I am afraid. Very heavy on opinion, very light on facts, and can’t even read a graph correctly.

                40

              • #
                Philip Shehan

                Pardon me I was mislead by the adjustment lines in the middle panel.

                They indicate a downward adjustment with later date. I did not notice the units on the vertical scale either of the middle or third panel.

                But that is precisely the point of the rest of my comment.

                It is the change in temperature, not the temperatures themselves that matter when you are trying to determine if they have risen or fallen and how much.

                The adjusted temperatures clearly lower the later temperatures relative to the older temperature, or raise the older temperature relative to the later. Six of one half a dozen of the other.

                As I wrote above:

                So the adjustment reduces the change in temperature over time whichever way you do it.

                So the statement “The adjustments always seem to add to global warming.” is wrong.

                The adjustments have reduced the amount of warming over the period.

                05

              • #
                Philip Shehan

                Tanner, you wrote

                The graph of the adjustments looks like the adjustments have been down “cooling the present” however it is a graph showing that the amount of adjustment to the historical temperature has reduced over time (smoke and mirrors)

                I am not quite sure what you mean here, but the slope of the adjustment line is steeper in the post war period because of the increased rate of growth of asphalt and concrete and heat producing industries which cause the UHI.

                05

              • #
                Tanner

                Philip

                Apology accepted. The middle panel adjustment lines are misleading as it looks like the present temperatures have been adjusted down as you supposed and not the past adjusted up. Think of how many others reached the same conclusion (hence the smoke and mirrors comment).

                No – not six of one half a dozen of the other! The temperatures which have been affected by the UHI effect have been retained thereby including the UHI effect in the temperature record!

                It is good to see that Hansen made an attempt to adjust for UHI, but if the UHI effect has contaminated the present temperatures then surely it is better to adjust the contaminated temperatures or exclude them from the “temperature” calculation.

                Hansen noted the importance of station selection, which, is exactly what Anthony Watts has been working on for the USA temperature record.

                I think that the worlds temperature records have been subject to so many adjustments and “homogenising” that they can no longer be relied upon.

                There may be a warming trend over the last 150 years or so, but how much of that warming is natural and how much is man made (CO2 and temperature adjustments). I have yet to see evidence of any measurable warming effect from CO2!

                40

              • #
                Philip Shehan

                Tanner, actually I just wasn’t paying attention with the trend line.

                They have added it to the raw data to produce the adjusted data. I just looked at it and assumed they were subtracting it (which still seems more logical to me as the newest data is really most corrupted by the urban heat island effect, and the steeper trend shorter, and it seems more sensible to remove the artefact from the data set than entrench it over the whole set. But that was a faulty assumption on my part.

                So I did not bother looking to see that would have given the adjusted temperature scale with lower rather than higher values.

                But as I said the temperature difference over the time period which are what matters as far as determining how much warming (or cooling) has occured, which is what I meant by six of one half a dozen of the other.

                As for how reliable old data is. Yes its a problem, but I think the adjustments are reasonable and unless we are going to throw the baby out with the bathwater as far as comparing the temperature records go, we have to live with it. But perhaps the uncertainty bands should feature more often on the graphs.

                See my comment on BEST data in my long reply to Griss above, (not the short one, which typically he has rejected out of hand because it does not suit him) when it gets out of awaiting moderation.

                12

              • #
              • #
                Philip Shehan

                Tanner, still confusing myself about the adjustment line.

                You would have to subtract the “mirror image” (in the horizontal plane) of the lines as they appear on the graph, that is with the slopes going up from left to right, with the largest subtraction being for the latest data.

                I think that’s right, but sometimes I can’t see the WFT.

                03

            • #
              Philip Shehan

              G,

              At least you have stopped referring to the “correspondence” (letter to the editor) as a “paper” which your reference source incorrectly calls it.

              It is also incorrect about the relationship between BEST and Hadcrut, Giss and NOAA temperatures.

              And the third error is that the discussion is about global land and sea data, not land data.

              It is a damning indictment of nothing.

              http://joannenova.com.au/2014/09/the-mysterious-sudden-jump-in-melbourne-temperatures-in-1996-with-an-instrument-change/#comment-1577611

              12

              • #
                Rereke Whakaaro

                At least you have stopped referring to the “correspondence” (letter to the editor) as a “paper” which your reference source incorrectly calls it.

                Of course, you are quite correct, we should all know that the word “paper” has ceased to be a synonym for “correspondence”, or “letter” or “written communication” (whether written or typed), or even “missive”, when referring to climate science.

                We consistently fail appreciate the fragility of the egos involved — our bad.

                Perhaps, to avoid confusion, we should always express the concept as “paper[TM]“; when referring to a scientific paper, because of all the money involved?

                40

              • #
                Philip Shehan

                Rereke. It has nothing to do with egos, nor has it anything to do with money.

                In scientific parlance a “paper” appearing in a peer reviewed journal designates original research which has gone through the peer review process.

                It can also be used to describe a lecture delivered at a conference.

                To represent a letter to the editor, or correspondence, which contains nothing but the opinions of the correspondent about a real paper published in the journal with no original data and is not peer reviewed as a paper is claiming a status for those opinions that they are not entitled to.

                Nature, from historical usage, uniquely uses the term “letter” as label for original peer eviewed but short original research. I think Watson and Crick’s manuscript on the double helix was classified as a letter.

                So one must be careful to distinguish between letters and correspondence published in Nature.

                01

        • #
          James Bradley

          I read it, Phil – looks to me like the early regional data sets are adjusted down but the modern urban data sets are unaltered because the urban affect is considered to be negligible – I’d say that’s an incorrect assumption.

          It’s seems to be just a load of waffle used pull the wool over folks’ eyes and rationalise how ‘the end justifies the means’ in case an warmist suffers a moral delema.

          31

          • #
            the Griss

            “It’s seems to be just a load of waffle used pull the wool over folks’ eyes ……”

            You describe Phillip to a tee !! :-)

            21

          • #
            Philip Shehan

            James, From the text:

            Why does the urban influence on our global analysis seem to be so small, in view of the large urban warming that we find at certain locations (section 5)? Part of the reason is that urban stations are a small proportion of the total number of stations. Specifically, 55-60% of the stations are rural, about 20% are small town, and 20-25% are urban, with some temporal variation. In addition, local inhomogeneities are variable; some urban stations show little or no warming, or even a slight cooling, relative to rural neighbors. Such results can be a real systematic effect, e.g., cooling by planted vegetation or the movement of a thermometer away from the urban center, or a random effect of unforced regional variability and measurement errors. Another consideration is that even rural locations may contain some anthropogenic influence [Mitchell, 1953; Landsburg, 1981]. However, it is clear that the average urban influence on the meteorological station record is far smaller than the extreme urban effect found in certain urban centers….

            We conclude, as already reported by Jones et al. [1990] and Peterson et al. [1999], that theurban effect on global temperature change analyses is small compared with the magnitude of global warming. Our estimate is that the anthropogenic urban contribution to our global temperature curve for the past century (Figure 4) does not exceed approximately 0.1°C

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              James Bradley

              Yet, Phil, the insignificant urban data is graphically regurgitated to demonstrate catastrophic warming trends and relied on as a source representation for funding, grants and subsidies by those promoting warming actavism.

              Again, a load of waffle, the graphs aren’t even interesting because they are based on ‘what-would-happen-if-we-did-this-to-the-raw-data’ algorythms.

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              Philip Shehan

              James, it was not an assumption, it was a finding.

              The reasons for that finding are explained in the text, and quantified. And given how little of the earth’s surface is taken up by urban centres, the quantity seems generous to me.

              But it does not support your prejudices so on the basis of no evidence whatsoever, you dismiss it out of hand with the usual attacks and insults thrown in.

              This is utterly typical of “skeptic” argument.

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              Geoff Sherrington

              Philip,
              It might help you to know that BOM adopt a choice for Acorn, by preferring to fix the most recent temperature and to adjust older ones.
              ZThis choice dictates thatba site undergoing steady UHI today will stand little chance of correction unless there is comparison with adjacent, non-UHI sites. However, there is no known way to detect and quantify UHI at ll Acorn and comparison sites. Even if it was wuantified forva dite, chances are that the present temp would stsy fixed, even though it was established as too warming.
              A fundamental problem exists.
              BOM claim global warming for the nation of 0.9 deg C since 1910.
              There are many cases ofbadjustme

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          the Griss

          Hansen, Jones, GISS..

          roflmao..

          You always choose the VERY WORST references :

          Because…. you are you. !!!

          You have NOTHING…

          You are nothing. :-)

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    pat

    kind of on topic…

    29 Sept: SMH: Megan Levy: Sydney weather: unseasonal hot spell won’t last long
    But don’t pack away your warm clothing just yet. The temperature is expected to ***peak at 21 degrees on Wednesday, but it is expected to feel significantly colder…
    “It’s going to be windy, so while the temperature is going to be 20 or 21 degrees [on Wednesday] it’s going to be a very windy day so it will probably feel more like the high teens.”
    Mr McBurney said the temperature on Tuesday would be just shy of Sydney’s hottest September day on record, which was in 1964 when the mercury hit 34.6 degrees. Sydney also experienced a 33-degree September day in 2012.
    The Hunter Valley is also forecast to hit 33 degrees on Tuesday, while Bourke is forecast to reach 35 degrees…
    “Essentially what we’re having is a cold front coming across south-eastern Australia [on Tuesday]. Ahead of that cold front, we have a trough that is dragging down hot air sourced from the interior…
    http://www.smh.com.au/environment/weather/sydney-weather-unseasonal-hot-spell-wont-last-long-20140929-10ndax.html?google_editors_picks=true

    kind of off topic, but great fun:

    28 Sept: WesternMorningNews: Ex-minister Owen Paterson warns climate change fears more damaging to the planet than global warming
    The ex-Tory minister added the pause in global temperatures rising each year has been so long it is “old to enough to vote”…
    Speaking at a fringe event at the Conservative Party conference in Birmingham, he said: “I think the climate has always been changing. The CO2 we are putting in the atmosphere is bound to have some impact. What it is, I’m not a scientist.
    “But I can read the numbers. There has not been a temperature increase now for 18 years. Some people say 26 years.
    “The pause is old enough to vote. The pause is old enough to join the Army. The pause is old enough to pay its taxes. We were never told the pause was coming along.
    “There are about 30 different explanations for the pause. Nobody explains why the pause is suddenly going to disappear and we’re going to go to get back on a track upwards.”
    He added: “I am concerned that the measures we are taking to counter projected dangers may actually be causing more damage now than those dangers.”…
    Asked directly whether he believed there was “no” man-made climate change, Mr Paterson said: “There’s an element. The climate has always been changing.”…
    http://www.westernmorningnews.co.uk/Ex-minster-Owen-Paterson-warns-climate-change/story-23011402-detail/story.html

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    pat

    28 Sept: IBT: Mark Piggott: Astronauts Who Helped Kickstart Environmental Movement Say Climate Change is ‘Bogus’
    Charlie Drake and Walter Cunningham’s photos inspired environmentists, but say their images were ‘exploited’
    Their stunning images of a fragile Earth seen from space helped start the global environmental movement, but, speaking at the Starmus science festival in Tenerife, astronauts Charlie Duke and Walter Cunningham declared that research into climate change is “bogus” and claim their photographs were exploited by environment campaigners.
    According to today’s Sunday Times, Duke, who took pictures of Earth aboard an Apollo 16 mission in 1972, and later became a Christian, told the conference: “Climate science is bogus. The world has got no warmer for more than 15 years. It is a great irony that the images taken on the Apollo mission have been used in this way. We helped to start it [the environmental movement] but I do not agree with it.”
    Walter Cunningham, who was aboard Apollo 7 in 1968, said: “Climate change is one of the greatest scientific fiascos of all time.”…
    Other speakers at the festival included Richard Dawkins, Stephen Hawking, and Queen guitarist Brian May, who is an astrophysicist.
    There is no suggestion other guests at the festival shared the views of either Duke or Cunningham.
    http://www.ibtimes.co.uk/astronauts-who-helped-kickstart-environmental-movement-say-climate-change-bogus-1467557

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      safetyguy66

      Seems to be a bit of a correlation between astronauts and AGW skeptics. Wonder if its as high as 97%?

      I also liked “Queen guitarist Brian May, who is an astrophysicist”. As opposed to “Leonardo Decaprio who is also a tool.”

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      safetyguy66

      Also…

      “Rick Wakeman and Brian May performing live on stage in Tenerife! Friday, 26th September 2014″

      Damn I would have sat through 3 days of Al Gore to end up seeing that.

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        the Griss

        Wear “noise-cancelling” headphones….

        ….. and take them off when Gore has finished! :-)

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          Annie

          Noise cancelling head sets don’t seem to cancel speech for me. They just dull it a bit. The same with ‘muzak’. They are best for ‘steady’ noise like aircraft engines.

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    pat

    apologies for a final O/T before i disappear. a good day for sceptics:

    28 Sept: Pittsburgh Tribune-Review: Editorial: The climate debate: Better science
    By The Tribune-Review
    A new study, surely unsettling for “settled science” climate cluckers, concludes that natural change in ocean winds, not human activity, accounts for the rise in Pacific Northwest temperatures over more than a century.
    Just as unsettling for climate alarmists is that this study is peer-reviewed, published in the Proceedings of the National Academy of Sciences and based on wind, barometric pressure and temperature data from 1900 through 2012.
    It is solid science supporting a most inconvenient truth for the blame-mankind crowd…
    Further diminishing the dwindling credibility of “science” twisted to fit a predetermined agenda, this study is another reason to reject climate alarmism as the cynical, politically motivated fraud it is.
    http://triblive.com/opinion/editorials/6847107-74/climate-science-settled#axzz3EfJ65BDN

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    the Griss

    Now that you have drawn BOMs attention to this., They will adjust the slope of the pre-change temps to match the post change slope.

    No thought of actually bringing down the new values to match the old, of course.!

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    I’ll never forget one afternoon in Melbourne, it was scorching hot, 45 degrees celsius according to the thermometer next to Flinders st. train station – then suddenly a cold change blasted in from the south. It was like someone had poured ink over the sky, from brilliant clear sky, the sky when black, with heavy rain and thunder. And in the space of 20 minutes, that thermometer dropped down to 15c.

    In Melbourne, no matter what the weather forecast, you always bring a raincoat.

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      GM2

      No matter what the weatherman/woman/person of non specific gender says re-Melbourne at some part of the day he/she/it will be right.

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      Carbon500

      Sounds like the UK!

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        Annie

        A little bit like only more so! You have to experience a Melbourne ‘Cool Change’ to appreciate it fully!

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      LevelGaze

      Eric -

      That must have been that afternoon i was sunning myself on the beach at Half Moon Bay!

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      Annie

      We’ve experienced that several times Eric Worral. It happened just yesterday again. In our case we weren’t actually in Melbourne but it had already hit the city. We were returning towards Melbourne from East Gippsland. The temperature dropped very quickly from 25C to 13C. By the time we through the Dandenongs and over the Black Spur it was 6C!

      We’ve been in the city and experienced just what you describe and also at Chelsea on the Bay…a wind change about 160 degrees and a drop of 20C in 3 minutes!

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    Grant (NZ)

    Maybe the AWS are able to be remotely controlled by climate models.

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    the Griss

    Is there a respective jump in say Sydney or Brisbane, on the introduction of AWS systems ?

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      Ian George

      The one thing that I found was a large building went up near the new AWS in 1996-97. This comes from the ACORN site’s history of ACORN stations.

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    Geoff Sherrington

    Tom,
    AFAIK, thermometer temperatures continued to be taken at Melb Regional for some years after the instrument change.
    Why not ask BOM if they have some parallel data they can give you?
    Geoff

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      GM2

      You want to ask the BoM for DATA,are you crazy,they haven’t seen hide nor hair of data for at least 25 years,models they have by the dross,they’ve got plenty to give away free of charge(well maybe not so free considering).

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        GM2

        sorry,that should read gross not dross.Gross is definitely the correct word
        1)Unattractively fat or bloated.
        2)An amount equal to twelve dozen; 144:

        But then again Dross
        1)something regarded as worthless; rubbish.
        I know, gross dross!

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    TdeF

    At first I thought drought, but previous severe droughts did not lift Melbourne average maxima.

    There may be a clue though in the photograph. The boxes are on the Exhibition garden side, so all new buildings are on the South and overshadowing from the hot North would be impossible, you would think. So look at the picture of the boxes on the corner in Google Earth, the corner of a triangular yard 25 metres x 14 metres and near Victoria Street. Now turn on historical imagery, which unfortunately only goes back to 2000. There you will see in 2000 potentially a great big tree, probably an elm in full leaf on the North West side of the fence and in Victoria Street, probably shading the whole area of the boxes in the afternoon.

    In the recent high resolution Google picture published previously, there is no tree at all in this position, so no shade. Was the tree removed for a specific reason like overshadowing? How long had the tree been there? Note that the tree on the NE side remains, but I have no idea how old it is. We are only looking for a step function difference of only 1 degree. Permanent summer shading this could be a full explanation of the maxima, Stevenson box or not. Is there an aerial or street photograph of Victoria Street from before 1990 which shows these trees?

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      TdeF

      If fact perhaps five trees, potentially on the same triangle on the North West and Western side. Most are gone by the 2003 photograph and all by the 2009 photograph where the boxes are completely exposed. Possibly they would not have affected the minimum temperature though, as sunlight was not involved. Of course that does not explain the step function as back as 1996, but maybe there was another tree removed earlier? The remaining street tree looks new in size, so perhaps a big tree was cut down with the start of Elm Disease into Victoria? Whole streets were lost with the drought and lack of watering. It would only take one tree.

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    Mikky

    I’ve noticed this sudden jump in very late 20th century temperatures in several Australian stations. A consistent change is probably regarded by homogenisation algorithms as a natural climatic event, but of course there can be consistent man-made changes, such as a switch at multiple sites to Automatic Weather Stations.

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      TdeF

      In the light of the attention on accurate measurements from such instruments, was there a BOM program to clean up the Stevenson box sites and make them more ‘accurate’? It would be simple enough to do, to remove shrubbery and trees from around the boxes. Sensible too. However the only direction temperature measurements could go in such an event would be up.

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    lemiere jacques

    a thermometer measures its own temperature….
    the point is nobody exactly know what is the measure done by a station..its physical meaning is complex, its value is its constance, the only feature that makes it useful.

    It is a signal with a taste of temperature of the air around the station…that s all.

    Thinking wa are able to reconstruct historical glaobla temperature is an assumption ( an optimistic one) …as long we don’t have another independant measure of it to test it…it is a game.

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      Philip Shehan

      lemiere, “nobody exactly know what is the measure done by a station.” You in fact answer this pretty well with your statement. “It is a signal with a taste of temperature of the air around the station.”

      That may be all but it is enough, combined with other such measurements, (tens of thousands globally) where random errors tend to cancel out and give an pretty accurate picture.

      The number of stations decreases as you go back in time, and so the margins of error for the calculated values increase, as you will notice on graphs which bother to include the error margins. Proxy data also match older instrumental data.

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      • #
        Winston

        Or alternately,

        ….and where deliberate errors tend to accumulate, and give a thoroughly inaccurate (but desirable) picture.

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    Carbon500

    Re. the comment in the article that: “The break may be due to the shorter response time of thermistors compared to mercury thermometers. This would put the reason for the break on a better footing than a ‘statistical’ explanation.”
    This point of view is supported by a statement in a book by the late British meteorologist Robin Stirling, who wrote ‘The Weather of Britain’ (ISBN 1-900357-06-2).
    On p286 of the book (published in 1997) he says “For some years now there have been temperature records from isolated places, and electronic recording is becoming more widespread as it saves labour. However there is a snag: the response time of digital instruments is much quicker than than the mercury in a glass thermometer, so that maximum and minimum readings a few tenths of a degree higher and lower than those recorded by an ordinary thermometer may occur.”

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    Oh good. Thermistors. I really hope not. Long term stability is a problem with them.

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      Yonniestone

      A ‘Thermistor’ is a good replacement word for a “Warmist’ as they’re very sensitive to temperature changes and give over inflated data.

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    Let alone problems with self heating due to the current flowing through them. I really hope somebody competent designed the circuitry.

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    Peter C

    Climate is what we expect. Weather is what we get.

    It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so

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  • #

    A couple of years parallel operation would be nice. Five would be better.

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      macha

      Now that would be too scientific for Bom. Ha. For an a bunch of so called specialists, so much seems so amaturish.

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        Greg Cavanagh

        One would expect a year overlap at minimum when changing a device type.
        And to be honest, an amature would do that simply because he wasn’t sure.

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    Seems there is a similar temperature disconnect in the Adelaide record as well. The rate of change is dramatically different after 1996. http://eyesonbrowne.files.wordpress.com/2013/01/west-tce-kent-town-max-temps-unadjusted1.jpg

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    the Griss

    Question.. does anyone know how often Automatic Weather Stations are calibrated?

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    Tim

    Surely somebody could run a simple experiment?

    Get an AWS and a thermomemter, run them together in the same place for a few months.

    Nto too difficult is it?

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      Leo G

      Yes, it has been done.
      There is often a difference of up to 1 degree Celsius.
      The problem is that the self-heating of RTDs affects their accuracy in some applications, such as air temperature measurement. These devices carry an electric current, typically 20 milliampere, which has a heating effect. The devices are calibrated under conditions where the sensor is immersed in a liquid bath, so calibration minimises the self-heating effect during calibration but not in service conditions.

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    Leo G

    Has the appearance of self-heating error for the RTD, where the effect is minimised during calibration checks, but not in service use.

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    Roy Hogue

    The ACORN adjustments make no corrections to the max record in 1996 but there is an adjustment made to the minima then. Hmm. — Jo

    If I was interested in proving something and thought adjustment of the temperature record would do it, I would certainly adjust the floor upward, not the ceiling. The rising floor, if true would demonstrate my point a lot better than the ceiling. What your climate is doing is much better illustrated by looking at the lowest temperatures reached overnight. The highs bounce around a lot.

    The morning low is what I look at to tell me what the trend is locally. We’ve gone from mid 60s (F) of summer to high 50s and then mid 50s, a harbinger of fall, even though 80 and 90 degree days have continued to happen.

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      Roy Hogue

      And yes, I know my daily morning lows are just indicators of the weather or perhaps more accurately, the seasons. I would need a lot longer record before it could begin to tell me anything about the local climate.

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    Arno Arrak

    Looking at your Figure 1 I am not surprised to see a temperature break. I am surprised to see it in 1996, however, and the 1998 super El Nino that should follow is entirely missing. When you look at the satellite temperature record which has weekly, not yearly, resolution and is global (see figure 15 in “What Warming?”)you will see a break in 1999, just after the super El Nino has subsided. In three years it raises global temperature by a third of a degree Celsius and then stops. This step warming is the only warming we have had since 1979 and is followed by a flat “hiatus” region we are still in. It is likely that this step up is caused by the huge amount of warm water the super El Nino carried across the ocean. It is not clear, however, why this sudden warming should become permanent. Your graph shows an upward slope after the break, something absent from the satellite record. It is just flat except for the ENSO oscillation that starts up again in 2008.

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      the Griss

      ” In three years it raises global temperature by a third of a degree Celsius and then stops. This step warming is the only warming we have had since 1979″

      YES !!! Well said, Arno ! :-)

      It is the STEP change that all warmists HAVE to include to show any warming at all in the satellite period.

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    pattoh

    Perhaps the BoM should just stick to calling whatever they do “weather” & leave the measuring of climate to empirical measurements of dam inflows & crop yields per Ha. /sarc.

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    handjive

    Apocalyptic Groundhog Day …

    30 September 2014, 5.20am AEST
    Human hands are all over Australia’s hottest ever year

    https://theconversation.com/human-hands-are-all-over-australias-hottest-ever-year-32267

    … and that is why the ‘sudden mysterious jump’ …

    Worst apocalypse. Ever.

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    James Strom

    In your figure 1 both the absolute temperatures and the slope of the trend change significantly at 1996, as I’m sure everyone noticed. If you were monitoring a process in a lab, and came up with results like that, you would check, recheck, and recheck your instrumentation and methods, particularly if they (instrumentation and methods) had changed at that point.

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    steverichards1984

    Strange, it says in their:

    http://www.bom.gov.au/climate/change/acorn-sat/documents/ACORN-SAT_Observation_practices_WEB.pdf

    “The transition between AiG and MiG thermometers and the electronic PRTs is provided in Table 8. Most sites show a transition to PRTs beginning during the mid-1990s. New sites during this period were exclusively installed with PRTs. However, most Bureau-staffed stations continue to maintain both the manually read thermometers and PRTs. The manual data such as reset temperatures are recorded in the A8 field book. ”

    That the old style readings and the new style readings are maintained…..

    I wonder where they are?

    Do they need help digitising the manually recorded readings?

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    Yonniestone

    Just caught a snippet of 9′s ‘Today’ with their weatherman Steve Jacobs claiming the hottest 2 consecutive Spring days ever in 73 years blah blah blah…..now considering he’s making statements for official records you would think 9 would have at least someone qualified to verify these claims? even more so considering the information above regarding the collection of climate data.

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      James Bradley

      Yonnie,

      Pity they didn’t use the same parameters when reporting the ‘hottest evvva’ summer in 2013 – I’m sure had they done so they’d have found a few hotter in the 50′s and 60′s.

      Seems they don’t mind shifting the data sets when it suits their political agenda.

      Problem is once you lock into a ‘hottest evvva’ then you need to continue to exceed that record otherwise you risk the public discovering a pause, or worse, a decline.

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        Yonniestone

        Very much like the problem with pathological lying where people lose track of what lies they’ve told and they overlap catching them out.

        I actually like Steve Jacobs as an entertainer/presenter not so much as a peddler of trash journalism disguised as scientific facts.

        Interesting he came from a WIN TV kids show in the 80′s as locally on WIN NEWS we had Jane Bunn a qualified Meteorologist as a weather presenter for 5 years and is very respected for her accurate forecasts, I can’t find much linking her to Climate alarmism as she seems to stick to facts, far different to larger MSM presenters.

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    Gregory

    The scientific way would seem to be running them together for five years before terminating the old tech.

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    the Griss

    Apart form buildings put up which might have caused the step, by reflection, or changing wind patterns or….?

    .. it might be interesting to look at traffic statistics over that last little period.

    A build-up of traffic congestion, combined with the fast response time of the new measuring gear could easily account for the slope.

    Was there a road opened somewhere that funnelled more traffic into this area?

    That’s the problem with city locations, you never know what could cause quite major changes.

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    [...] Jo Nova: Here’s a strange change. After 160 years of fairly constant maximum temperatures, the raw Melbourne records take a sudden step up by 0.7 0C in 1996. Coincidentally (or not) that is the same year that the automatic gauge was installed. The new electronic equipment is much more responsive to short peaks and dips compared to thermometers. Could the step up be due to the better resolution? It’s by no means definitive — these are yearly averages, not monthly, and it may be a real climate shift and not due to the equipment. The obvious question is whether this sort of jump occurs in other stations where AWS (automatic weather stations) were installed. That would have profound implications if it did, but surely it would have been noticed already?  [...]

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    dribble

    The newer Stevenson Screen installations have a very heavy steel post and stand underneath the the screen. Older screens had a triangular stand which tried to keep most of the steel mass away from underneath. It would not surprise me in the slightest if the heat coming off the newer stands, which goes straight up into the screen, affects the temperature. This would be particularly the case on sunny windless days. I looked at the BOM’s paper on the changeover to the new standard model Stevenson screen and it did not mention the effect (if any) of the stand.

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