HadCRUt4: revision or revisionism?

Guest essay by Christopher Monckton of Brenchley

As Bob Tisdale has recently pointed out, the monthly temperature anomaly series published by the Hadley Centre and the Climatic Research Unit at the University of East Anglia has just been extensively revised.

A commenter on a previous posting about the temperature record asked whether the entire 163-year HadCRUt4 dataset could be displayed graphically, with the uncertainties (red and green) and trends illustrated. Here is the requested graph, based on the revised data:

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The least-squares linear-regression trend across the entire 1959-month period shows warming equivalent to 0.47 Cº/century (0.9 Fº/century), well within the natural variability of the climate. The 95% (2 σ) confidence interval falls between 0.33 and 0.6 Cº/century, as shown by the trend-lines flanking the central trend.

The result should be adjusted to allow for the finding in Michaels & McKitrick (2007) that urban heat island effects and other extraneous influences over the past 30 years have led to overestimation of the warming rate over land by as much as double. On the assumption that this bias may have existed since 1850, the true warming rate since then is equivalent to just 0.4 Cº (0.7 Fº) per century.

The bounds of the 2 σ confidence interval converge because measurement uncertainties are thought to have diminished with improvements in methods and reliability.

On the other side of the account, terrestrial coverage has declined sharply over recent decades. For this and other reasons, the HadCRUT4 record takes explicit account of three distinct species of uncertainty: measurement and sampling, bias, and coverage. Combining the effects of these three, the 2 σ uncertainty bounds today are approximately one-sixth of a Celsius degree either side of the central estimate:

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In March 2013, for instance, the central estimate of the anomaly was +0.412 Cº. However, the lower and upper bounds of the 2 σ interval were given as 0.249 Cº and 0.569 Cº, respectively 0.163 Cº and 0.157 Cº distant from the central estimate.

The discrepancy between the projections in the IPCC’s Fifth Assessment Report (red central projection bounded by orange region) and the outturn in HadCRUT4 (bright blue trend-line) is startling. The difference between the observed cooling at 0.86 Cº/century and the predicted warming of 2.33 Cº/century is equivalent to a hefty 3.2 Cº/century.

However, the period of record since the backcast “predictions” began in 2005 is short. And one does not want to suggest that part of the reason why the HadCRUt4 projections show steeper cooling than the satellite datasets is that the terrestrial results are now being tuned to bring them into correspondence with the more accurate and complete satellite results, and that, since the 20th-century warming has been – as it were – enhanced, there now has to be a corresponding disenhancement of the 21st-century warming.

The head of the World Meteorological Organization tried to have me thrown out of the Durban climate conference in December 2011 because I had dared to question his assertion that one should study temperatures over 30-year periods. I had politely pointed out that the warming and cooling phases of the Pacific Decadal Oscillation each last 30 years, so that to cancel them out one should either study periods that are multiples of 60 years or study periods centered on the year of a warming-to-cooling or cooling-to-warming phase transition.

“Are you presuming to lecture Me?”, he bellowed. The event was captured on film by one of my CFACT colleagues, and the WMO’s flimsy pretext for having me banned was that it had not given permission for the filming. So I skydived into South Africa from a great height and told the organizers that they had made the mistake of acting unreasonably within a formerly British jurisdiction, so that their actions would be subject to judicial review.

They said they were immune from judicial review (as they are about to find out, this is not the case). But, since the local papers had had enormous fun at their expense because they had tried to ban me, they let me back into the conference.

With that background, here is the graph of temperature change in the 60 years since 1953:

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The warming rate throughout the period during which we could in theory have influenced global temperatures has been equivalent to just 1.14 Cº/century.

The period since 1990, the year of the first IPCC Assessment Report, falls more or less neatly either side of the warming-to-cooling phase transition in the Pacific Decadal Oscillation in late 2001, broadly canceling any bias from this and the related ocean oscillations (see Tsonis, 2006, for an interesting discussion). Here is the graph:

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The warming rate is not much distinguishable from that since 1950: it is up by less than 0.3 Cº/century. Besides, as the IPCC is now learning to its cost, one cannot draw any conclusion from the relative slopes of multiple arbitrarily-chosen trend-lines on the same data about the rate at which global warming is accelerating.

There have been some significant changes between HadCRUt3 and HadCRUt4. In the earlier dataset, the warming rates from 1860-1880, 1910-1940 and 1976-1998 – the most rapid supra-decadal warming rates in the entire record – were statistically identical at 1.6 Cº century, as Lord Leach of Fairford discovered on St. George’s Day, 2009, when he asked Her Majesty’s Government –

“… whether the rate of increase in global mean surface temperatures between 1975 and 1998 was similar to the rates of increase observed between 1860 and 1880 and between 1910 and 1940 …”

Lord Hunt of King’s Heath replied –

“Observations collated at the Met Office Hadley Centre and the University of East Anglia Climate Research Unit indicate that the rate of increase in global average surface temperature between 1975 and 1998 was similar to the rates of increase observed between 1860 and 1880 and between 1910 and 1940 (approximately 0.16 C° per decade) [1.6 Cº/century]. …”

There is a tendency towards progressive revisionism in the terrestrial temperature datasets, in a manner calculated to depress temperatures substantially in the earlier part of the record and to nudge them upward a little in more recent times (but not by too much: the satellites are watching).

The effect of this tampering has been inexorably to steepen the apparent rate of warming since 1850, so as to sex up the dossier and make global warming seem to be a bigger problem than it is. This tendency, long evident in the untrustworthy NASA GISS dataset (J. Hansen, prop.), is also detectable in the HadCRUt series.

A version of HadCRUt3 more recent that that used in Lord Hunt’s answer gives warming rates equivalent to 1.0, 1.6 and 1.8 Cº/century respectively over the three periods. HadCRUt4 continues the tampering trend. It gives warming rates equivalent to 1.0, 1.4 and 1.9 Cº/century respectively. The following revealing table summarizes the changes:

Data source 1860-1880 1910-1940 1976-1998
Lord Hunt, 2009 1.6 Cº/century 1.6 Cº/century 1.6 Cº/century
HadCRUt3, 2011 1.0 Cº/century 1.6 Cº/century 1.8 Cº/century
HadCRUt4, 2013 1.0 Cº/century 1.4 Cº/century 1.9 Cº/century
Going down a lot Going down a little Going up and up

It is almost as though Lord Hunt’s answer, demonstrating the inconvenient truth that the three most rapid supra-decadal warming rates in the global instrumental record were statistically identical, and implying that there has been little or no man-made acceleration in global warming, caused such concern among the usual suspects that they dropped it down the memory-hole, replacing it with successive new and more politically-correct versions of the Party Line.

Yet even the highest of the exciting, freshly-minted supra-decadal warming rates in HadCRUt4, at 1.9 Cº/century, is less than half the warming rate equivalent to 3.9 Cº/century that prevailed for 40 years in Central England (and, inferentially, globally) from 1695 to 1735. Those four decades entirely preceded the onset of the Industrial Revolution in 1750. We could not have been to blame. It was (and largely still is) the Sun, stupid.

Accordingly, even on the much-altered HadCRUt record, the anthropogenic component is in the warming observed since 1850 seems rather small and difficult to detect. As Bob Tisdale has pointed out (and if you have not seen his slide-show on el Niño events and global temperature change, you should), even the historically warm temperatures since 1998 were elevated to their new plateau in a step-change by the naturally-occurring Great El Niño of that year.

Fred Singer has been pointing this out for years, but the usual suspects have kept their fingers in their ears, preferring to conduct bogus and insulting pseudo-psychological surveys about why skeptics are skeptical rather than looking at the most obvious reason why skeptics are skeptical: the science itself.

Professor Ian Plimer says that there is some evidence to suggest that undersea volcanic tremors occur in the equatorial eastern Pacific for six months before each el Niño begins there. If so, the el Niños, including the Great el Niño of 1998 and its two predecessors over the past 300 years, are of volcanic and not of anthropogenic origin.

For how long has there been no statistically-significant warming? In the following graph, the zone of statistical insignificance is shown in pale blue. Since the entire central trend-line falls within that zone, the warming since February 1996, more than 17 years ago, is not statistically distinguishable from zero.

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On the evidence summarized in these graphs, there is no rational case for taking drastic and costly steps to mitigate global warming. It will be cheaper, and wiser, to wait and see.

More detailed and larger graphs are available in this PowerPoint file: wuwt-hadcrut4

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45 thoughts on “HadCRUt4: revision or revisionism?

  1. The timing of this article is interesting since I have just left a comment on the Bishop Hill blog under the article relating to “Met insignificance” reading:

    “Whilst all of this is of great interest, it is over looking one important fact, namely that the thermometer record is accurate and reliable to tenths of a degree.

    At the crux of all of this debate is the realistic assessment of the margins of error in temperature measurments/assessments made as from the 1850s to date and to what extent more receant measurements/assessments may have become polluted by station drop outs, poor station siting, UHI and the like.

    I suspect that when a realistic assessment of the bounds of errors involved is made, we cannot say whether it is today (ie., 2013) warmer than it was in the early 1880s, or in the 1930s/1940s.

    For sure there have been temperature fluctuations (some up and some down) and it is almost certainly the case that there has been some warming trend since the 1850s, but within that I do not accept that we can say with a high degree of certainty that the peaks in and around the early 1880s and the 1930s/1940s are not about equal to the temperatures today.

    That I consider to be a more fundamental issue and one which is often over looked.

    May 28, 2013 at 10:53 AM | ricard verney”

    The first plot provided by Lord Monckton validates the point I make.

    When one considers the margins of error, it is not possible to assert definitively that the temperature today (2013) is warmer than it was in the early 1880s. In fact, it appears that the temperature today could have a positive anomaly as low as about 0.2C whereas the temperature in the 1880s could have a positive anomaly as high as 0.7degC.

    A more reasonable assessment of the potential margins of error is that today the temperature could have a positve anomaly of about 0.4degC and the 1880s as high as 0.7degC.

    It may have been warmer in the early 1880s than it is today. That is quite a remarkable possibility (I am not saying that it was warmer, merely that we do not know one way or the other), given the increased concentration of CO2 in the atmosphere and if CO2 possesses the warming property/climate sensitivity claimed.

  2. The longer they keep their thumb on the scales, the more embarrassing the correction will be when they realise that Gaia isn’t playing ball.

  3. It is also worth remembering that the El Chichon and Pinatubo volcanoes artificially amplified the warming trend, when measured from 1980 to date (for both), and 1990 to date (for Pinatubo).

    This occurred because temperatures in the first half of the period concerned were depressed by the volcanoes, and consequently had an effect on the least squares trend.

    Based on GISS guesstimates of the volcanoes’ effects on global temperatures, potentially a third of the warming trend since 1980 could be due to this factor.

    http://notalotofpeopleknowthat.wordpress.com/2013/05/12/how-chichon-pinatubo-affected-temperature-trends/

  4. I just posted the following on the “Met Office sets the cat amongst the pigeons” thread. Having read all 200 or so posts on the thread, and ignoring (for the time being) the ongoing agitation being generated by Mssrs. Stokes, Hardman, et al, many replies were simply remarking on ‘just how cold it is right now’. Germany was flagged up, the UK, Cleveland, New York, Brisbane, and later, France.

    Ok, so this is directed to all those out there who still remain resilient in their belief of CAGW – especially when Lord Monkton has added, yet again, more ammunition for our skeptic cause. This is a golden opportunity to finally set the record straight once and for all. We’re throwing down the gauntlet. This is a simple question which brings us back down to earth (pun intended) . . . .

    Please can you tell me (and every other regular WUWT reader like me who is in total disagreement with AGW);

    WHAT COUNTRY, RIGHT NOW, IN THE WORLD, IS SIGNIFICANTLY WARMER THAN IT NORMALLY IS FOR THIS TIME OF YEAR?

    I look forward to your reply.

  5. Do the folks at CRU keep audit trails showing what data was altered, when, by how much, and why?

    Just Curious. Does anyone know?

  6. GeeJam says:
    May 28, 2013 at 3:51 am
    /////////////////
    It is not Southern Spain.

    I normally go swimming around Easter, say late March/early April. My swimming pool is usually about 21/23degC which I find to be rather cold but just bearable for a short period.

    This year I have not yet been swimming. About 10 days ago my pool was up to about 22degC but then dropped back down to 16degC. It is now about 22/23degC. I would expect at the end of May for it to be 25 to 28degC.

    In summary, temperatures in Southern Spain are about 2 months behind the norm. The beginning of January, and the end of January/beginning of February was quite nice with air temperatures for a few days around 25 to 27degC, but ever since then it has been unseasonally cold and in relative terms very windy. The sun is strong, but the air is cold.

  7. WHAT COUNTRY, RIGHT NOW, IN THE WORLD, IS SIGNIFICANTLY WARMER THAN IT NORMALLY IS FOR THIS TIME OF YEAR?

    [please don't use caps. It is unnecessarily rude and offensive to others. If you feel you need to make a point in this way, it usually indicates it's not much of a point . . mod]

    Finland is!

  8. I’ve been looking at the CRUtem3 dataset and found all manner of cheating.
    Iceland: Teigarhorn: “Adjustments” made with a sine rule – http://www.flickr.com/photos/7360644@N07/8584716096/
    England: Manchester: Data shifted 8 years forward – http://www.flickr.com/photos/7360644@N07/8603419994/
    Argentina: Santa Cruz: Data changed by seemingly creating a “ghost” station with the desired values. (On my to do list.)
    UK: Eskdalemuir: Inexplicable adjustments – http://www.flickr.com/photos/7360644@N07/8608595979/
    Southern England: Data selection from 14 stations. 11 used for the 1960’s, but only Bournemouth Hurne for the 2000’s.
    England: Bournemouth Hurne: adjusted for some years, not others – http://www.flickr.com/photos/7360644@N07/8608827498/
    UK: Stornoway: Inexplicable adjustments – http://www.flickr.com/photos/7360644@N07/8602676098/
    Iceland: Grimsey: coldest station drops out in 1970 – http://www.flickr.com/photos/7360644@N07/8593023081/
    And so on.

  9. “…so as to sex up the dossier and make global warming seem to be a bigger problem than it is”

    David Kelly comes to mind.

  10. “The result should be adjusted to allow for the finding in Michaels & McKitrick (2007) that urban heat island effects and other extraneous influences over the past 30 years have led to overestimation of the warming rate over land by as much as double. On the assumption that this bias may have existed since 1850, the true warming rate since then is equivalent to just 0.4 Cº (0.7 Fº) per century.”
    //////////////////////////////////////////////////

    Whilst I remain unconvinced that the effects of UHI and the effect of this on the land based thermometer record have been properly studied, or is properly understood or known, I suspect that its impact is greater as from about 1960 (may be a little earlier around 1950) and extends into the 1990s with diminishing influence thereafter. I rather doubt that it had much impact before the 1930s at the very earliest. There are a number of factors supporting that view such as the date of large scale suburbinisation, air travel (and the expansion of airports), car ownership, tarmacing over large areas for parking, building out of town shopping centres etc .
    I am therefore sceptical of the validity of the assumption that the bias has existed (or may have existed to any significant extent) as from 1850. I suspect that if it did exist, its influence and extent was less, and it becomes more of an issue post about 1960 (or may be a little earlier).

  11. I would like to see a plot of the “uncorrected” anomalies developed from the “unmanipulated raw” temperature data (used by the various organizations to produce the “official” anomaly plots).

    I presume that “unmanipulated” data would show very large scatter and much less apparent “heating” of the climate. In other words, it would be visually obvious to anyone that the “raw data” provides no basis for AGW fears — and, at worst, is less than scientifically useful.

    An “unmanipulated anomaly” plot would be a worthwhile addition to the WUWT reference section — if its not there already (and I missed it).

  12. If a portion of the HadCRUt4, for the 163 year period, is due to natural recovery from the Little Ice Age, and a portion from Urban Heat Effect, then there’s not much left for increasing human Carbon ladened gas to do. If the Great el Nino and it’s two predecessors are volcanic, then Earth’s fission rate must be variable….Motive Force for All Climate Change was posted four years ago.

  13. I very much appreciate this article. It is very simply written and I could follow the thread of thought clearly

    I find the bit about volcanic eruptions on the seabed interesting. I have often wondered if they have an effect on the circulation of deep ocean water movements which could be magnified.

  14. To me, this points out why it is ridiculous to use a 30 year period for “climate”. It’s pretty obvious that there are 3 cycles of slight warming/cooling on that graph, with warming peaks around 1880, 1945, and 2005 and cool dips around 1910 and 1978. These are approximately 60-70 year cycles. As I understand it these cycles can be traced back to the 1500s in the hurricane record. We seem to have just crested a warming portion and if so, can expect a continuation of cooling for a few decades.

    Underlying these cycles (hey, did any of the “climate scientists” ever actually study what causes those cycles?) is a slight trend of increase. Is it the continuation of the warm-up from the LIA? And if so, what was the cause of the LIA and why is it warming? Is there actually an answer, or are the CO2 theorists still pretending the LIA didn’t exist?

    It’s also possible that the underlying trend shows the result of increasing urbanization. Or meddling with records, or increasing accuracy since switching from eyeballs on mercury thermometers to electronic measurements.

    Bottom line: I personally see no acceleration of warming, no correlation between CO2 emissions and that slight warming, nothing at all to be alarmed about. In fact, the only thing possibly alarming to me is the possibility that the second half of my life will be lived in a cooling, crappy climate with the possibility of seeing food shortages and horrific hurricanes and tornadoes, and paying too much to heat my home.

  15. The supposed human influence on climate, instead of becoming more clear as one would expect, with C02 reaching levels (supposedly) not seen in 800,000 years is melting away faster than an ice floe in the mid-day summer’s sun. It’s hilarious to watch the comedy show of climatists casting about wildly for “reasons” why the warming has stopped, such as Trendberth’s claim that the warmth has decided to heat the deep oceans instead, or side-stepping the issue altogether and just pointing at weather events as “evidence”. One wonders how much longer the charade can continue.

  16. I used to like using Hadcrut3 because they did not play around with the data and restate it every month like NCDC and GISS do (actually they do it even more often than monthly).

    But now with Hadcrut4, it seems Hadley and the Met Office have decided to join the crowd and start adjusting their numbers every month. It is now version Hadcrut 4.2.0.0 – they even have four digits set aside for future changes.

    http://www.metoffice.gov.uk/hadobs/hadcrut4/data/versions/version_numbering.html

  17. “The least-squares linear-regression trend across the entire 1959-month period shows warming equivalent to 0.47 Cº/century (0.9 Fº/century), well within the natural variability of the climate.” This raises the question as to whether there is a good estimate of the natural variability. I have looked quite hard for any assessment. Without finding any thus far, I have got a long way towards developing my own (Nature rejected a first pass, so they probably felt I was onto something). I would be grateful if anyone could point me to a decent estimate of the natural variability.

  18. richard verney says:
    May 28, 2013 at 4:15 am
    “This year I have not yet been swimming” (southern Spain).

    Thanks Richard. Only Melbourne says it’s having a milder than average Autumn according to WUWT replies so far.

    But it’s colder than normal for this time of year in Germany, Mid West USA, North Carolina, New York, UK (nationwide), Brisbane, France & Southern Spain.

    Anyone else care to tell us of other countries/regions where there is evidence of ‘significant’ warming for this time of year? As we know, GISS anomalies for May won’t be available for while.

  19. Perhaps the team is praying for a large volcanic eruption, then they can claim accuracy and blame the volcano for the decline.
    Of course given behaviour to date, they will eventually concur with their critics, will insisting those critics were wrong.

  20. “The result should be adjusted to allow for the finding in Michaels & McKitrick (2007) that urban heat island effects and other extraneous influences over the past 30 years have led to overestimation of the warming rate over land by as much as double. On the assumption that this bias may have existed since 1850, the true warming rate since then is equivalent to just 0.4 Cº (0.7 Fº) per century.”

    Ah yes, the paper which assumed that the population of antarctica was 56Million people, and that St Helna had a population in the 10s of millions.. The same paper which assumed the population density of alaska was the same as California, and new jersey and utah. The paper which assumed that the population in the Gobi desert was the same as Bejing.. The same paper which used this population as a regressor.. The same paper that explained UHI by the regressor of literacy.. That paper?

    I suppose one could imagine that the UHI bias went back to the 1850s at the same rate as this bogus result. Perhaps it was the airports and Jet engines in 1800’s, or the air conditioners.

    If we work hard enough at this we can disappear the LIA, or rather we can find ourselves in a position where we have to say that it is no warming than in those days when the Thames froze. Damn ice must be in on the conspiracy.

  21. The Iceman Cometh says:
    May 28, 2013 at 6:06 am
    I would be grateful if anyone could point me to a decent estimate of the natural variability.
    =========
    the estimate depends on the statistical model used.

    http://bishophill.squarespace.com/blog/2013/5/27/met-office-admits-claims-of-significant-temperature-rise-unt.html

    the underlying problem is that a lot of statistics assumes that climate data is “normal”, which assumes the data will follow the bell curve. however, there are many other possibilities. For example, the repeating cycle of ice ages and interglacials tends to suggest bi-modal or cyclical data. We see this cyclical bi-modal activity on smaller and larger scales, which suggests we may be dealing with a chaotic fractal. A strange attractor. Something like the Lorenz attractor, which shows a system orbiting two preferred states,much like we see in the climate data over both long and short terms.

    https://en.wikipedia.org/wiki/File:Lorenz_attractor_yb.svg

    have a look at the Lyapunov exponent. Matlab has the improved method implemented, based on some recent mathematical work on chaos. Likely other libraries do as well. you should be able to calculate this exponent for the various temperature series available to see if they are chaotic (positive Lyapunov exponent). If they are, then attempts to predict temperature via computer models are likely futile. this would likely make a great WUWT article, which in the end is likely to be much more widely read than most scientific journals.

  22. Mike McMillan

    David Kelly was an honourable man who was only interested in the truth, as represented by the data.

    Unfortunately there are also many victims of the policies being pursued in the name of global warming/climate change. Fuel poverty in the older generation has reached unacceptable levels, as have excess deaths through cold this winter.

  23. Bruce Cobb says:
    May 28, 2013 at 8:23 am
    ——————————–

    Various data sets from around the world, such as the Greenland ice cores, show that each succeeding warm period has been cooler than the previous. That is, the Minoan Warm Period was toastier than the Roman, which was balmier than the Medieval, which was more clement than the Modern, which we now enjoy.

    We’re headed inexorably out of this interglacial toward the next glacial.

  24. Re: volcanic sourcing of released El Nino heat.

    The vulcanism itself has not (I very much doubt) enough energy to turn over the deep oceanic waters, but long wavelength disturbances might push waters above or into upwelling zones, i.e. pushing processes beyond a threshold for at least a short-time effect.

    We see Argo data of 0-700 & 700-2000 m lumped into large time periods as if there were two layers that we were not interacting. I’m surprised we aren’t seeing a continuous profile by year, so-as to determine in there is a warming pulse that comes from below.

    The deeper waters are warming at twice the rate of the surface waters. That immediately strikes me as a warming from below that loses heat at the top more efficiently than it loses it to higher water layers. Since we know there are thermoclines, this is of no surprise. But the time element of the heat transfer is not being discussed.

    If volcanic action (including the energy gained through mass movement of water, possibly the principal was the earth-quake/volcanic activity is removed) is significant, we should see a transfer of deep energy to shallow energy through time and the column.

    We need more time and depth change information from Argo. It could be that the data is insufficient for this, but even that would be telling us something to look for.

  25. It must be terrible for the record keepers to know their fiddling is being watched. You are such a nuisance your lordship. Keep it up.

    “calculated to depress temperatures substantially in the earlier part of the record and to nudge them upward a little in more recent times”

    I believe Hansen was the earliest practitioner of what I have termed the “Thumbtack Adjustment Method” for the temperature record. I believe the tack is inserted in the early 40s and the record levered counterclockwise. It was used in the late 90s by GISS to push that pesky 1936 instrumental record high down below the 1998 El Nino high. I’ve always hoped that some one would actually do this to see how close the result is to the revised highs. I’m not very good at this type of graphical manipulation.

  26. From Steven Mosher on May 28, 2013 at 7:49 am:

    Ah yes, the paper which assumed that the population of antarctica was 56Million people, and that St Helna had a population in the 10s of millions.. The same paper which assumed the population density of alaska was the same as California, and new jersey and utah. The paper which assumed that the population in the Gobi desert was the same as Bejing.. The same paper which used this population as a regressor.. The same paper that explained UHI by the regressor of literacy.. That paper?

    Wow. Who pissed in your Wheaties?

    I don’t see where you found all that in the McKitrick and Michaels 2007 paper. Googling “michaels mckitrick 2007 56 million” goes nowhere.

    Finally tracked it down to where you stirred up some muck at Judith Curry’s blog when they were looking at a new McKitrick paper.

    http://judithcurry.com/2012/06/21/three-new-papers-on-interpreting-temperature-trends/#comment-211553

    Five years after intense peer-review and with many hordes of warmists wanting to tear McKitrick down, you suddenly found something so amazing that it totally tore the paper apart. You emailed McKitrick your great and grandiose findings, didn’t like the reply, and spent time pointing out the other many flaws with those commenting how McKitrick was always an incompetent hack as has been thoroughly detailed at Deltoid.

    Would you mind writing up all those findings of yours as a WUWT guest post? Maybe you’ll finally force that well-deserved retraction out of that weasel McKitrick, that you have so obviously been hungering for since last year.

  27. Re: Mosher 7:49 am on Michaels & McKitrick (2007) (preprint) that urban heat island effects

    Ah yes, the paper which assumed that:
    the population of antarctica was 56Million people,
    and that St Helna had a population in the 10s of millions.
    … population density of alaska was the same as California, and new jersey and utah.
    population in the Gobi desert was the same as Bejing..

    What Michaels and McKtrick wrote in their preprint on line:
    On Antarctica:
    This left 451 usable locations. 11 cells are in Antarctica, where there is no economy to speak of, several countries share jurisdiction over different research sites, and there is an anomalously high rate of missing values, probably due to the extreme conditions in which data are collected, so these were also removed.
    After removing the Antarctic stations only 95 out of 440 remaining cells (22%) had at least one missing month, and only 5 (1% of the sample) had more than 12 months missing.

    Helna is not mentioned. Neither is St. Helena.
    But St. Helena Island has 1400 people crowed into two towns.
    Note worthy in Google Earth is an outsized tarmac (Falkland’s War Era?) at the Royal Air Force Station Ascension (-14.438794,-7.9842234). I wonder where the weather station is? And how it might have changed.

    On “Alaska”
    Magee, N., J. Curtis, and N. Wendler (1999), The urban heat island effect at Fairbanks, Alaska, Theor. Appl. Climatol., 64, 39– 47

    On “Gobi”,
    Jones et al. [1990] ran a similar comparison on three regions: Eastern Australia, Eastern China and Western USSR. Their definition of ‘‘rural’’ included towns of up to 10,000 in the USSR and up to 100,000 in China.
    GDP density in China is 0.16 million$/square km while in the US it is three times higher, at 0.47 million$/square km and in Canada it is only one third as large, at 0.05 million$/square km.

    So, Steven, what are you talking aobut? He is referring to what appears to be a blunder in the gridding of population density. [Please provide us with a link next time.] So the M&M2007 gridding is un.

    Nevertheless, on the subject of UHI effects, the changes over time in population, economy, and facilities locally around the weather stations is the key point about UHI contamination.
    The few inhabited and growing places in Antarctica shouldn’t represent the continent without a big caution.
    Fairbanks shouldn’t represent the state of Alaska, much less be unchanged before and after the Pipeline in 1977.
    Major facility changes on small islands ought not be ignored,
    and population centers of 90,000 ought not be considered rural anywhere.

    Has the M&M2007 gridding study been revised in later papers?

    Has the M&M2007 gridding study been revised in later papers?

  28. Dear Mod, delete this if you feel it’s inappropriate:

    The CRUtem3 Santa Craz “ghost” station, I previously alluded to. Only 23 monthly values.

    879140 -500 685 -999 SANTA CRUZ PUERTO ARGENTINA 19201958 101920
    1920 151 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1921 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1922 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1923 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1924 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1925 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1926 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1927 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1928 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1929 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1930 -999 -999 -999 -999 -999 -999 -999 -999 -999 79 133 144
    1931 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1932 156 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1933 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1934 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1935 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1936 -999 -999 94 -999 -999 -999 -999 -999 -999 95 -999 -999
    1937 151 146 117 103 51 42 24 28 72 -999 -999 -999
    1938 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 119 -999
    1939 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1940 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1941 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1942 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1943 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1944 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1945 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1946 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1947 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1948 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1949 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1950 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1951 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1952 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1953 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1954 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1955 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1956 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1957 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999
    1958 -999 111 -999 -999 -999 -999 36 43 63 119 122 135

  29. @ Ferd Berple – Thanks for your suggestions, The data I am studying seems to be something like a truncated normal once detrended. I think it important that the properties of this data don’t seem to change from millennium to millennium during the Holocene up to ~8kyBP. I seem to be converging on ~0.8 deg C per century, up from ~0.5 deg C per decade, as the standard deviation. I would be very happy to have some other estimates. I came across Trenberth et al in AR4 “The standard deviation of the HadCRUT3 annual average temperatures for the globe for 1850 to 2005 shown in Figure 3.6 is 0.24°C. The greatest difference between two consecutive years in the global average since 1901 is 0.29°C between 1976 and 1977, demonstrating the importance of the 0.75°C and 0.74°C temperature increases (the HadCRUT3 linear trend estimates for 1901 to 2005 and 1906 to 2005, respectively) in a centennial time-scale context.” This can only be regarded as naïve – the standard deviation of annual temperatures can indicate very little about the standard deviation over a century!

  30. Bloke down the pub says:
    May 28, 2013 at 3:23 am
    The longer they keep their thumb on the scales, the more embarrassing the correction will be when they realise that Gaia isn’t playing ball.
    ==========================================================================

    Finally the Gore hypocrisy makes sense! He is trying desperately to warm the planet all on his own to meet model predictions!

  31. A further thought on the gridding problem Steven Mosher is on about regards Michaels & McKitrick (2007) (preprint) as also commented on by kadaka 10:56 am.

    Assuming Steven is right that M&M took a country’s population and divided by area to get a population density uniform across the country’s cells. But M&M didn’t stop there. They did this at more than one time period. So in the end, they were using the change in population density as a parameter in the study. The numerical value in the change in population density would be uniform in the grid and this is clearly unrealistic. At the same time, however, the percentage change in population density would also be uniform across the grid and that is justifiable first order assumption for a UHI effect.

    So, if the end result is that all stations are experiencing a UHI effect proportional to the GROWTH RATE of population in a country, and averaged out across all grid cells, I’m not convinced it is a gridding problem. Whether that adjustment is better than none at all might be debatable.

    Granted it would be better to know the population change in Fairbanks, Alaska over the past 100 years and equate a unique UHI value to that cell. Then do that same thing with the tens of thousands of other cells.

    Similarly, it would be better to know which trees bears and bucks fertilized in the past 200 years before some one cored them. I suppose you could also make the crude assumption that UHI is proportional to night-time light density at scales no smaller than 6 minutes lat and lon and ignore several socio-economic factors.

    In this case, a broad brush change in population density growth rate may do as a first-order proxy across the dataset when you lack finer data and funding.

  32. The result should be adjusted to allow for the finding in Michaels & McKitrick (2007) that urban heat island effects and other extraneous influences over the past 30 years have led to overestimation of the warming rate over land by as much as double.

    The main reason warming has been overestimated is decreasing aerosols and aerosol seeded clouds have resulted in increased early morning solar insolation, causing earlier and higher minimum temperatures.

    Which is not to say UHI and increasing urbanization haven’t contributed substantially. They have.

  33. So, if the end result is that all stations are experiencing a UHI effect proportional to the GROWTH RATE of population in a country

    There is a fair amount of mis-understanding about the effect of UHI on the surface temperature. Quite a lot of it by climate scientists, which to my jaundiced eye looks intentional.

    UHI per se doesn’t significantly affect the surface temperature over time (the anomaly). The main effect over time is from increasing urbanization, both horizontally, ie more buildings etc and vertically, ie taller buildings.

    In the developed world, growth rate of populations should be a good proxy for change in urbanization. Although not in Asia.

  34. Wow….Mosher has really stuck his neck out this time!
    Shouldn’t be hard for him to post the chapter, verse and line from the Michaels and Mc Kitrick paper wherein they claim the population of Antarctica is 56 million!

  35. RE: correction to 11:25 am Re St. Helena

    I conflated Ascension Island and Georgetown (Google Earth put a St. Helena ref on Ascension) with Saint Helena and Jamestown.
    The Air Station on Ascension is 7°58’06″S 14°24’9″W

    Saint Helena does not have an airport, but it seems they are building one:
    (Panaramio pic at 15°57’53″S 5°38’53″W). Jamestown is one crowded village.

    There is a Panaramio Picture: “From the MET Station”
    15°56’37″S 5°40’01″W
    And this looks like a place that UHI is not a problem.
    Whether it has always been there is another question.

  36. However with Hadcrut3, the slope for the last complete 30 years is no higher than the slope for a 30 year period 70 years ago, despite the fact that CO2 is now the highest in history. See:

    http://www.woodfortrees.org/plot/hadcrut3gl/from:1900/plot/hadcrut3gl/from:1912/to:1942/trend/plot/hadcrut3gl/from:1983/to:2013/trend

    #Selected data from 1912
    #Selected data up to 1942
    #Least squares trend line; slope = 0.0154487 per year
    #Selected data from 1983
    #Selected data up to 2013
    #Least squares trend line; slope = 0.0150735 per year

  37. We know that the rainfall cycle is thirty years and can therefore assume that this applies to other weather and climate cycles too. If this is the case then no period under sixty years is actually trustworthy and period less than this should only be used as a general guide.

  38. Ever since McKitrick tore apart the crappy BEST paper idolised by Mosher, he’s been in a huff and wasted no inch of space to slime McKitrick.

  39. Jeremy Shiers says:
    May 29, 2013 at 7:27 am

    Why fit a straight line to data which clearly has cycles.

    People have been talking about fitting cycles to temperature data but I haven’t seen anyone actually doing it. So I had a go.

    Check these out.

    Multi-decadal oscillation pluse recovery from LIA:

    http://wattsupwiththat.com/2009/03/20/dr-syun-akasofu-on-ipccs-forecast-accuracy/

    2500 years:

    http://wattsupwiththat.com/2011/12/07/in-china-there-are-no-hockey-sticks/

  40. “Finally the Gore hypocrisy makes sense! He is trying desperately to warm the planet all on his own to meet model predictions!”
    Maybe this is the anthropogenic global warming according UNFCCC ?

  41. There is a tendency towards progressive revisionism in the terrestrial temperature datasets, in a manner calculated to depress temperatures substantially in the earlier part of the record and to nudge them upward a little in more recent times (but not by too much: the satellites are watching).

    There is a built-in conflict of interest here. I would ask would this be allowed in other areas?
    If businesses could audit their own accounts, and set their own accounting standards, what do you think might happen?
    If pharmaceutical companies could devise the tests for the efficacy of their own drugs, what do you think might happen?
    If a manager could sign off their own expenses, what do you think might happen?
    If the prosecution could decide what was admissible as evidence in every criminal case, what do you think might happen?
    People are passionate about what they do, and even those that are scrupulously honest will have a built-in bias towards their own case. A lack of independent standards and controls, tends to give incentives to dishonesty. Which is why the most honest favor checking. For them it merely improves the accuracy and quality of what they do,

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