2015/08/14

What I cannot understand about Professor Robert Brown of Duke University.

A post at wuwt data fudging / incompetence:
Problematic Adjustments And Divergences (Now Includes June Data)

Rgbatduke June 10, 2015 at 5:52 am [the full entry]

The two data sets should not be diverging, period, unless everything we understand about atmospheric thermal dynamics is wrong. That is, I will add my “opinion” to Werner’s and point out that it is based on simple atmospheric physics taught in any relevant textbook.

This does not mean that they cannot and are not systematically differing; it just means that the growing difference is strong evidence of bias in the computation of the surface record. This bias is not really surprising, given that every new version of HadCRUT and GISS has had the overall effect of cooling the past and/or warming the present! This is as unlikely as flipping a coin (at this point) ten or twelve times each, and having it come up heads every time for both products. In fact, if one formulates the null hypothesis “the global surface temperature anomaly corrections are unbiased”, the p-value of this hypothesis is less than 0.01, let alone 0.05. If one considers both of the major products collectively, it is less than 0.001. IMO, there is absolutely no question that GISS and HadCRUT, at least, are at this point hopelessly corrupted.

One way in which they are corrupted with the well-known Urban Heat Island effect, wherein urban data or data from poorly sited weather stations shows local warming that does not accurately reflect the spatial average surface temperature in the surrounding countryside. This effect is substantial, and clearly visible if you visit e.g. Weather Underground and look at the temperature distributions from personal weather stations in an area that includes both in-town and rural PWSs. The city temperatures (and sometimes a few isolated PWSs) show a consistent temperature 1 to 2 C higher than the surrounding country temperatures. Airport temperatures often have this problem as well, as the temperatures they report come from stations that are deliberately sited right next to large asphalt runways, as they are primarily used by pilots and air traffic controllers to help planes land safely, and only secondarily are the temperatures they report almost invariably used as “the official temperature” of their location. Anthony has done a fair bit of systematic work on this, and it is a serious problem corrupting all of the major ground surface temperature anomalies.

The problem with the UHI is that it continues to systematically increase independent of what the climate is doing. Urban centers continue to grow, more shopping centers continue to be built, more roadway is laid down, more vehicle exhaust and household furnace exhaust and water vapor from watering lawns bumps greenhouse gases in a poorly-mixed blanket over the city and suburbs proper, and their perimeter extends, increasing the distance between the poorly sited official weather stations and the nearest actual unbiased countryside.

HadCRUT does not correct in any way for UHI. If it did, the correction would be the more or less uniform subtraction of a trend proportional to global population across the entire data set. This correction, of course, would be a cooling correction, not a warming correction, and while it is impossible to tell how large it is without working through the unknown details of how HadCRUT is computed and from what data (and without using e.g. the PWS field to build a topological correction field, as UHI corrupts even well-sited official stations compared to the lower troposphere temperatures that are a much better estimator of the true areal average) IMO it would knock at least 0.3 C off of 2015 relative to 1850, and would knock off around 0.1 C off of 2015 relative to 1980 (as the number of corrupted stations and the magnitude of the error is not linear — it is heavily loaded in the recent past as population increases exponentially and global wealth reflected in “urbanization” has outpaced the population).

GISS is even worse. They do correct for UHI, but somehow, after they got through with UHI the correction ended up being neutral to negative. That’s right, UHI, which is the urban heat island effect, something that has to strictly cool present temperatures relative to past ones in unbiased estimation of global temperatures ended up warming them instead. Learning that left me speechless, and in awe of the team that did it. I want them to do my taxes for me. I’ll end up with the government owing me money.
However, in science, this leaves both GISS and HadCRUT (and any of the other temperature estimates that play similar games) with a serious, serious problem. Sure, they can get headlines out of rewriting the present and erasing the hiatus/pause. They might please their political masters and allow them to convince a skeptical (and sensible!) public that we need to spend hundreds of billions of dollars a year to unilaterally eliminate the emission of carbon dioxide, escalating to a trillion a year, sustained, if we decide that we have to “help” the rest of the world do the same. They might get the warm fuzzies themselves from the belief that their scientific mendacity serves the higher purpose of “saving the planet”. But science itself is indifferent to their human wishes or needs! A continuing divergence between any major temperature index and RSS/UAH is inconceivable and simple proof that the major temperature indices are corrupt.

Right now, to be frank, the divergence is already large enough to be raising eyebrows, and is concealed only by the fact that RSS/UAH only have a 35+ year base. If the owners of HadCRUT and GISSTEMP had the sense god gave a goose, they’d be working feverishly to cool the present to better match the satellites, not warm it and increase the already growing divergence because no atmospheric physicist is going to buy a systematic divergence between the two, as Werner has pointed out, given that both are necessarily linked by the Adiabatic Lapse Rate which is both well understood and directly measurable and measured (via e.g. weather balloon soundings) more than often enough to validate that it accurately links surface temperatures and lower troposphere temperatures in a predictable way. The lapse rate is (on average) 6.5 C/km. Lower Troposphere temperatures from e.g. RSS sample predominantly the layer of atmosphere centered roughly 1.5 km above the ground, and by their nature smooth over both height and surrounding area (that is, they don’t measure temperatures at points, they directly measure a volume averaged temperature above an area on the surface. They by their nature give the correct weight to the local warming above urban areas in the actual global anomaly, and really should also be corrected to estimate the CO_2 linked warming, or rather the latter should be estimated only from unbiased rural areas or better yet, completely unpopulated areas like the Sahara desert (where it isn’t likely to be mixed with much confounding water vapor feedback).

RSS and UAH are directly and regularly confirmed by balloon soundings and, over time, each other. They are not unconstrained or unchecked. They are generally accepted as accurate representations of LTT’s (and the atmospheric temperature profile in general).
The question remains as to how accurate/precise they are. RSS uses a sophisticated Monte Carlo process to assess error bounds, and eyeballing it suggests that it is likely to be accurate to 0.1-0.2 C month to month (similar to error claims for HadCRUT4) but much more accurate than this when smoothed over months or years to estimate a trend as the error is generally expected to be unbiased. Again this ought to be true for HadCRUT4, but all this ends up meaning is that a trend difference is a serious problem in the consistency of the two estimators given that they must be linked by the ALR and the precision is adequate even month by month to make it well over 95% certain that they are not, not monthly and not on average.

If they grow any more, I would predict that the current mutter about the anomaly between the anomalies will grow to an absolute roar, and will not go away until the anomaly anomaly is resolved. The resolution process — if the gods are good to us — will involve a serious appraisal of the actual series of “corrections” to HadCRUT and GISSTEMP, reveal to the public eye that they have somehow always been warming ones, reveal the fact that UHI is ignored or computed to be negative, and with any luck find definitive evidence of specific thumbs placed on these important scales. HadCRUT5 might — just might — end up being corrected down by the ~0.3 C that has probably been added to it or erroneously computed in it over time.
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What I would like RGB to answer is:

He is basically stating that all major providers of temperature series of either
1 being incompetent
2 purposefully changing the data to match their belief.

IF 1. How can so many intelligent educated people be so incompetent. This seems very unlikely. Have he approached the scientists concerned and shown them where they are in error. If not, Why not?
IF 2. This is a serious accusation of scientific fraud. As such have he approached any of the scientists involved and asked for an explanation? If not, why not? he is part of the same scientific community.
Can he give reasons why he thinks scientists over the whole globe would all be party to the same fraud. Do climate scientists live in luxury mansions taking expensive family holidays - perhaps he could provide proof?. What manages to keep so many scientists in line - are there families/careers/lives threated to maintain the silence. why is there no Julian Assange or Edward Snowden, willing to expose them?


2 comments:

  1. Brown: HadCRUT does not correct in any way for UHI.

    They do.

    Brown: This bias is not really surprising, given that every new version of HadCRUT and GISS has had the overall effect of cooling the past and/or warming the present!

    Not sure if it is true, but the temperature record has a cooling bias. Thus one would expect that with increasing abilities to remove this, better algorithms and more data to see data quality problems, more of this cooling bias is removed.


    Brown: One way in which they are corrupted with the well-known Urban Heat Island effect

    But Brown "forgets" that stations in urban areas are not only affected by warming in their surrounding, but are also regularly moved away from the centre because the measurement conditions become too bad or because the meteorological office can no longer pay the rent. What matters is how much UHI did the station notice in the beginning and how much UHI it notices now. That is an empirical question and can go both ways. Evidence from many studies show that in practice urban series do not warm much more.

    Brown on UHI: water vapor from watering lawns

    The heat of the sun can either go into warming of the air or into evaporation. More watering means more evaporation and cooler temperatures. Irrigated regions are on average about 1°C cooler. The watering of vegetation in cities and especially suburbs is one reason for cooling biases in urban stations.

    In any case, the claim is wrong, the opposite is true.

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  2. Brown: GISS is even worse. They do correct for UHI, but somehow, after they got through with UHI the correction ended up being neutral to negative.

    Later in the text the "neutral to" is dropped. When this correction is negative it is extremely small. This is not as surprising as Brown seems to think. Urbanization only has a small effect and GISS nowadays uses data that is homogenized by NOAA by comparison with neighbours. This should remove most of the trend bias due to homogenization already and the additional correction for urbanization is actually not really necessary any more (they used to use raw data and maybe kept this correction for historical consistency).

    Brown: They might get the warm fuzzies themselves from the belief that their scientific mendacity serves the higher purpose of “saving the planet”.

    If this were the case Brown will have to explain why these fuzzies reduce global warming when they remove non-climatic changes in the temperature record. (The warming adjustments of the land temperatures, which WUWT likes to write about, are dwarfed by the cooling adjustments of the sea surface temperature.) My explanation would be that these scientists are trying to do a good job and try to be better than their colleagues to show how good they are.

    Brown: A continuing divergence between any major temperature index and RSS/UAH is inconceivable and simple proof that the major temperature indices are corrupt.

    I would have no problems when improving the surface temperature record makes the difference with satellite temperatures larger. If that is what the evidence shows, then that is what the evidence shows. The buggy satellite temperatures is just a minute part of the evidence. This data is full of non-climatic changes, which are very hard to correct because there is little redundant data. There are only two groups working on it and they dedicate only a small part of their time to it because there are no users (humans do not live up in the sky) and the satellite record is short and buggy. Sometimes nice for a global overview, but not the best for trends.

    he is part of the same scientific community.

    I think you are very generous. Scientists would at least inform themselves. And the confidence they display would at least fit somewhat to the expertise they actually have. With all the errors in the comment of Brown (and I only pointed out the most clear ones) and the overconfidence, I would not see him as a peer even if he has been granted to visit his home university as a visiting professor.

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