BIG NEWS – Verified by NOAA – poor weather station siting leads to artificial long term warming

I’ve been saying for years that surface temperature measurements (and long term trends) have been affected by encroachment of urbanization on the placement of weather stations used to measure surface air temperature, and track long term climate. In doing so we found some hilariously bad examples of climate science in action, such as the official USHCN climate monitoring station at the University of Arizona, Tucson:

USHCN weather station in a parking lot. University of Arizona, Tucson

I have published on the topic in the scientific literature, and found this to be true based on the science we’ve done of examining the USHCN and applying the siting methodology of Leroy 2010.

In Fall et al, 2011 we discovered that there was a change to the diurnal temperature range (DTR). It decreased where stations had been encroached upon, because of the heat sink effect of man-made materials (asphalt, concrete, bricks, etc.) that were near stations.

For layman readers that don’t know what diurnal variation is, it is the daily variation of temperature due to the variation of incoming solar radiation from rotation of the earth on its axis.

It looks like this:

Here is what we found; in the best-sited stations, the diurnal temperature range in the lower 48 states has no century-scale trend, but the poorly sited stations had a reduction in DTR:

These results suggest that the DTR in the United States has not decreased due to global warming, and that analyses to the contrary were at least partly contaminated by station siting problems.  Indeed, DTR tended to increase when temperatures were fairly stable and tended to decrease when temperatures rose. 

Fall, S., A. Watts, J. Nielsen-Gammon, E. Jones, D. Niyogi, J. Christy, and R.A. Pielke Sr., 2011: Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends. J. Geophys. Res., in press. Copyright (2011) American Geophysical Union.

A few years back in 2012, I noted that NOAA was doing an experiment to prove or disprove what we learned.

Initial funding was provided this year by the USRCRN Program for a multi-year experiment to better understand the thermal impacts of buildings with parking lots on air temperature measurements. A site near the offices of ATDD will be instrumented to measure accurately the air temperature and other variables at multiple distances from the potential thermal heat source, corresponding to the distances from thermal sources used in classifying USCRN stations (Figure 7).

This study will have several applied and practical outcomes. Determining the downwind range of influence of a typical building will be important for understanding built environment impacts on surface air temperature measurements. Other measurements of radiation and heat fluxes will help illuminate the physical processes responsible for any detected heat transfers. Finally, this information will help influence future USCRN/USRCRN siting decisions. Additional insight is being sought by collaborating with National Weather Service (NWS) and National Institute for Standards and Technology (NIST) on extensions of the basic project. This effort promises to be greatly useful to understanding climate quality temperature measurements and how they can be influenced by the station site environment.

They have finally published. (h/t to Steve Mosher) Guess what? Like I’ve said all along (and been excoriated for saying so) they found exactly what we did.

Impacts of Small-Scale Urban Encroachment on Air Temperature Observations

Ronald D. Leeper, John Kochendorfer, Timothy Henderson, and Michael A. Palecki

Abstract (bold mine)

A field experiment was performed in Oak Ridge, TN, with four instrumented towers placed over grass at increasing distances (4, 30, 50, 124, and 300 m) from a built-up area. Stations were aligned in such a way to simulate the impact of small-scale encroachment on temperature observations. As expected, temperature observations were warmest for the site closest to the built environment with an average temperature difference of 0.31 and 0.24 °C for aspirated and unaspirated sensors respectively. Mean aspirated temperature differences were greater during the evening (0.47 °C) than day (0.16 °C). This was particularly true for evenings following greater daytime solar insolation (20+ MJDay−1) with surface winds from the direction of the built environment where mean differences exceeded 0.80 °C. The impact of the built environment on air temperature diminished with distance with a warm bias only detectable out to tower-B’ located 50 meters away.

The experimental findings were comparable to a known case of urban encroachment at a U. S. Climate Reference Network station in Kingston, RI. The experimental and operational results both lead to reductions in the diurnal temperature range of ~0.39 °C for fan aspirated sensors. Interestingly, the unaspirated sensor had a larger reduction in DTR of 0.48 °C. These results suggest that small-scale urban encroachment within 50 meters of a station can have important impacts on daily temperature extrema (maximum and minimum) with the magnitude of these differences dependent upon prevailing environmental conditions and sensing technology.

And, we’ve published at AGU on the effects of siting on 30 year temperature trends:

The quality of temperature station siting matters for temperature trends

Anthony Watts / December 17, 2015

30 year trends of temperature are shown to be lower, using well-sited high quality NOAA weather stations that do not require adjustments to the data.



Figure 4 – Comparisons of 30 year trend for compliant Class 1,2 USHCN stations to non-compliant, Class 3,4,5 USHCN stations to NOAA final adjusted V2.5 USHCN data in the Continental United States

EMBARGOED UNTIL 13:30 PST (16:30 EST) December 17th, 2015

SAN FRANCISCO, CA – A new study about the surface temperature record presented at the 2015 Fall Meeting of the American Geophysical Union suggests that the 30-year trend of temperatures for the Continental United States (CONUS) since 1979 are about two thirds as strong as officially NOAA temperature trends.

Figure 3 - Comparisons of well sited (compliant Class 1&2) USHCN stations to poorly sited USHCN stations (non-compliant, Classes 3,4,&5) by CONUS and region to official NOAA adjusted USHCN data (V2.5) for the entire (compliant and non-compliant) USHCN dataset.

Figure 3 – Tmean Comparisons of well sited (compliant Class 1&2) USHCN stations to poorly sited USHCN stations (non-compliant, Classes 3,4,&5) by CONUS and region to official NOAA adjusted USHCN data (V2.5) for the entire (compliant and non-compliant) USHCN dataset.

Using NOAA’s U.S. Historical Climatology Network, which comprises 1218 weather stations in the CONUS, the researchers were able to identify a 410 station subset of “unperturbed” stations that have not been moved, had equipment changes, or changes in time of observations, and thus require no “adjustments” to their temperature record to account for these problems. The study focuses on finding trend differences between well sited and poorly sited weather stations, based on a WMO approved metric Leroy (2010)1for classification and assessment of the quality of the measurements based on proximity to artificial heat sources and heat sinks which affect temperature measurement. An example is shown in Figure 2 below, showing the NOAA USHCN temperature sensor for Ardmore, OK.


Figure 1 – USHCN Temperature sensor located on street corner in Ardmore, OK in full viewshed of multiple heatsinks.

Dare I call this new NOAA paper vindication?

Or, by doing so will the rabble of global warming zealots led by schmucks like Dr. Michael Mann find yet another reason to label me a “Koch funded science denier”?

I could use a beer right about now. You can support the work here.

340 thoughts on “BIG NEWS – Verified by NOAA – poor weather station siting leads to artificial long term warming

      • How quickly will “The Team” act to “Vanish” this paper of “Inconvenient Truth”?

    • “Any” normal person would know this just using common sense. Rocket science it ain’t.

      • Yes, but actual data is preferable to common sense. For a long time, common sense said heavy objects fall faster than light ones. Heavier than air vehicles could never fly.
        Anthony provided such hard data years ago. Now, NOAA is aware of this fact.

        • Yeah, well the last thing we need now is a bunch of empirical data when we have all of the computer models to paint the picture…

        • The world is awash in “actual data” and “professional” scientific analysis as well as “detached” reporting from “professional” journalists. So how come it’s B.S. from top to bottom?
          Science and reality have been hijacked by people who think their subjective truth makes the real facts irrelevant.

          • I note that the test towers are supposedly on “grass”. I wouldn’t turn the cows out on that if that’s what they’re calling it. It certainly doesn’t look like a natural environment to me.

          • Your comment “Science and reality have been hijacked by people who think their subjective truth makes the real facts irrelevant.” is true but needs a bit more explanation: Scientists – at least some of them who call themselves that – have fallen into the trap the media created. For years now the media have learned to assume that if any one of them reported something, it must be true. If something is reported as fact, no one else thinks they need to check.
            So this happens: A “scientist’ says something. If the media reports it – even if they miss-report the statement – other media pick up on it and repeat the error. Within about 10 seconds it becomes ‘fact’ and ‘consensus’.

          • The challenge is to get the TV indoctrinated to realize what both of you have iterated. “Most visited website on climate change” can’t quite compete with network TV.

        • I am sure NOAA was aware years ago…just could not find a reliable way to disappear it.

      • It is difficult for these zealots to grasp common sense when they are invested so heavily in a fraud, just look at all the Democrats running to gain the Democrat nomination or CNN. Same widespread illness.

    • Vindication yes, but will there be a effort to develop a systematic way to adjust past temperature records at compromised stations to properly account for these UHI effects or should we just throw them out?

      • Throw them out, as whoever who makes the the adjustments to data from badly placed weather stations controls the results according to their expectations.
        There needs to be a new series of measuring stations based N,N,E and W of UHIs at a range of distances to measure the effect of distance from the UHI as well as seeing what the effect of prevailing wind on temperature is.
        The cost should not be too great in comparison to building windmills or solar farms, and we would at least have some firm data.
        The local weather forecasters over here in the UK always finish their evening forecasts with ‘ the temperature in rural areas will be a degree or two lower than their previous forecast which is based on urban areas ‘.

      • Yes, they will adjust the highs upward at poorly sited stations to match the diurnal at well sited stations

    • BS! I talked to a farmer this week that said they have to buy different seed now because its so late and the ground is still too cold to germinate the usual seed!

  1. This new NOAA paper investigation is certainly a resounding vindication of the great work carried out by Anthony Watts over so many years. When even NOAA admits this, the message is finally getting through.

    • “When even NOAA admits this, the message is finally getting through”

      When it gets through the thick head of “Lord Deben”, aka John Selwyn Gummer of the UK’s Climate Change Committee, I might feel a little less depressed.

      “The deniers have lost the battle because the science is fundamentally clear”

      He might be right about “Crap” houses, but still wrong about everything else.

    • “Dare I call this new NOAA paper vindication?”

      What Toby, Brent, Nicholas Tesdorf and many many others all loudly agree, a very resounding vindication!
      With a hearty “Well Done!!”

      Now,if we can get NOAA to cease cooling the past and remove their rampant adjustments!

      • exactly……without their adjusting the past down….there would be no global warming at all

    • I will be charitable and presume that NOAA is looking for a graceful retreat from an untenable scientific position. This will allow them to ‘re-examine’ their past records and pronouncements with a plausible excuse of mere sloppiness and laxity.
      Perhaps an Emily Latella moment?

    • Who would have suspected that NOAA was being funded by nefarious oil interests? Shocking!

  2. Anthony, I’ve always had faith in your work on the siting of surface temperature stations. Every photo of a station that you have given as examples of the distortion caused by station siting has turned out to be validated by data derived in this latest study. You have every reason to say “I told you so.” Congratulations!

    In the wake of this result, it appears that the entire temperature record used by NOAA and GISS has been significantly overstated. It also appears to me that some of the warming that has been shown is more characteristic of UHI than of carbon dioxide. But will this quell the doomsayers? Probably not. Because this has always been more about power and control over human affairs than about climate.

    • Those of us living out here in Realville stopped listening to doomsayers a long time ago. When Democrat Socialists (they finally came out of the closet) are selling global warming instinct tells us it’s all about power and control over our lives. Also, I have noticed that where I live in Southern Arizona the summer highs have been slowly dropping since 1991. The lows have been getting slightly warmer due to increased moisture from the warm Pacific. This has been real climate change.

  3. Berkley Earth looked at tens of thousands of weather stations and concluded that urban heat wasn’t distorting the overall figures and that there was a clear warming trend.

    continuing to cherry pick urban weather stations and claiming this shows the evidence is not there for warming is not science or an adequate refutation of the scientific evidence.

    • Oh Griff PLEASE… Where exactly in this article did you read someone “claiming this shows the evidence is not there for warming”?

    • You know, I always thought “griff” aka Edward Griffin was dense, but this comment of his really takes the cake.

      By his comment, Griff shows he is incapable of assimilating new information, even when it comes from an official source.

      That’s the mark of a paid troll. Now, get the hell off my site. I’m done being nice to you.

        • There might be a little ‘fertilizer’ on the site.

          Anthony – you might be the most patient, armor-skinned human being I’ve ever come to be aware of.

      • Dammit! You booting griff the troll just FORCED me to donate $20 to your cause of ridding WUWT of trolls.

        Thank you for the work you’ve done and the work you continue to do. Like I said above, this Bud is for you!

      • Never thought I would see this day! NOAA doing actual science to check their surface station networks accuracy followed by an admission that it has a bias that runs counter to the warming meme? Then Anthony throwing the Grifftard off his site? Somebody wake me up, I must be dreaming!

        • Most of the time I just laugh at Griff’s non sequiturs and carry on reading down the line. For a while I was almost looking forward to his chiming in with the lamest of warmunist positions just so I could laugh and move on. Lately though, he has gotten just bothersome.

          We do need some pure doctrinal warmunists on the site though. Sometimes there is more good information in the rebuttals given by other commenters than there was in the original article. (Many of the articles, while informative, are on aspects of the problem I’ve already looked at, while the comments provide sources I’ve sometimes never seen.)

          • We still have Mosh and Nick, though Mosh has been reduced to drive by’s lately and Nick isn’t showing up very often.

          • I also do not want to see skeptic purity enforced as alarmist purity is enforced with an iron hand at various alarmists sites and “news” organs. However there is a big difference between thoughtful and informed counterpoints or just posting a joke on the subject at hand and the just plain ridged ideological bull hockey that Griff spouts. It is already difficult enough to sift through the chaff to get to the wheat in the comments in some places. Dr. Spencer’s otherwise excellent blog being a case in point where a few wackos inundate the site with their never ending arguments over the same points over and over and over again on most every post.

          • Yes, I could almost miss Griff. It’s the high-volume spammers like David Appell who can make a good blog like Roy Spencer’s become almost unreadable.

          • MarkW
            May 3, 2019 at 6:39 am

            We still have Mosh and Nick, though Mosh has been reduced to drive by’s lately and Nick isn’t showing up very often.

            To be fair, Steven and Nick have their own sites and work to do, which I’m sure occupies a lot of their time. How many of us here have spent much time on their sites to see what they’re up to, and comment on their work on their home ground?

            Sometimes they don’t get treated very well here, and there’s a bit of name-calling and insinuation that I’d rather not see directed toward people who are doing serious work. I know I’d trust results from them more than I would from Mann or The Gang.

            But this is Anthony’s Day of Affirmation, and a hearty congratulations to him and everyone who worked on that effort. A great job all around!

          • I’m with you, Owen. His comments were usually silly, and provided a guffaw. I also agree we need serious rebuttal consisting of real logic. Mosh is not bad at this, although his arguments have not been sufficient to do more than make me do more research – and conclude his comments were either inadequate of just misleading.

          • “…To be fair, Steven and Nick have their own sites and work to do, which I’m sure occupies a lot of their time. How many of us here have spent much time on their sites to see what they’re up to, and comment on their work on their home ground?…”

            They historically have posted frequently on any number of sites. Seems like Nick’s full-time hobby was posting 99% on sites other than his own.

            I have visited it many times. Usually he takes an argument he is losing here and spins it to his echo chamber to make it appear the opposite. At least he has not recently claimed that Anthony was deleting his posts here and swearing to never return here. “Comment on their work on their home ground?” Lol, give it a shot.

      • Here, here! Griff should have been booted a long ago after he slandered Dr Crockford and Willie Soon! He is a slime and does not deserve any time on any site.

        Anthony koodos for your continuing efforts to try a hold back the hoards of crazies from taking over this world and for constantly trying to bring reason, facts and integrity to the debate.

      • He’s not incapable of assimilating new information, he is unwilling to; especially new information that might not confirm his existing bias.

      • Anthony – you should “Suffer fools gladly”. Otherwise, we risk becoming as closed minded as the climate alarmists.

        • Walt,
          Griff is not a simple fool, he is either willfully ignorant, or more likely, here to disrupt serious conversation with outright lies and slander. Either way, I think we have all suffered him long enough.

      • He’s not ‘dense’ – he’s a deliberate hack and he damn well knows it.

        • Perhaps Griff is a lesson in Orwellian doublespeak. I think he should stay as an exercise of our critical thinking skills.

      • While I can’t recall ever agreeing with (or even respecting) anything Griff has posted, I think having people like him here is a good thing. If nothing else, it highlights our willingness to hear the other side.

        Of course, it also puts the other side on display, which is often laughable.

        • It’s true, Anthony. If Griff provides the best arguments for CAGW, then it is obvious to all what a waste that belief is.

        • Now if Dr Spencer would just boot appel from his site reading the comments might be just that nicer !

      • Spoken like “The Great One” Mark Levin, who is known for telling obnoxious callers to his talk radio program; “get off my phone, you big jerk!” Griff deserves it.

      • Anthony – Thank you for your final decision regarding ‘ole Griff (and thanks for the insider info in that he is in fact a he – I think the kids have a word for this – ‘Doxxing”? Did I get that right?). Over the years, Griffy-baby and I have have a few back-and-forths over his inane stances on most things regarding ‘sustainability’ (such as bio-fuel usage by the US Armed Forces during a future wartime situation) and a number of his dig-in-your-heels views on CAGW.

        However, on some level I will miss taking him out to the verbal woodshed from time to time. But, for the sanity of all concerned, probably best that he is gone.



      • God Bless you Anthony Watts. You took time to help your staff and neighbors through the fires and all of us Americans who love liberty and truth by looking for the warming trend in plain site. Be not weary in well doing.

      • Griff is so funny! Don’t kick him out please. His hilarious statements always spark interesting reactions. I understand your frustration, but why should you think he will ever change?

    • This work demonstrates that not only urban stations but also rural stations can be influenced by small-scale urban encroachment.

      • Indeed small-scale. But it is not only that. Small scale stuff other that buildings affect temperature. When a building is built, anomaly increases. When it is demolished the anomaly decreases. A statistical processing meant to remove these artifacts might actually end up detecting only one half (like painting the wall, fast process), but not the other half (paint slowly deteriorating). Which way these asymmetrical changes work, I have no idea. Stevenson screens at least would be affected.

        • That’s why the proper response when discovering such a problem is to increase the error bars. Not try to fix the data. Whenever you start fiddling with the data, you might make the data “better” for some periods, but you will end up making it worse for others.
          Beyond that, there will always be questions of timing as you point out.

          • MarkW
            The problem is, ‘climatologists’ rarely even use error bars. And, the general Rule of Thumb is that in adding numbers with different precision, all the numbers in the data set should be rounded off to the same precision as the least precise. That creates a whole lot of trouble for those trying to push two or three orders of magnitude greater precision for averages than the actual readings.

        • Hugs, your “detecting only one half” argument is one of the two objections I have to the Berkeley Earth process. As highlighted in one post from 2015,, we discussed how the scalpel could, ne should, cut a temperature at the rapid change of conditions at a station site, yet treat the gradual change (deteriorating paint, growth of nearby bushes and trees, population growth nearby) as real climate signal. However, the instances of site recalibration (replacement of thermometers, repainting, plant trimming), would be seen as discontinuities rather than vital recalibration information .

          The other half of my objection is firmly in the Fourier Space information content argument. A scalpel is a low cut filter — it removes low frequency information content. High frequency information content cannot be used to predict low frequency content. Climate is a low frequency signal. Therefore the BEST process removes the most critical information from the records before homogenizing.

          MarkW: Amen, Brother! It is amazing how many people forget that a “correction” is the addition of a signed value which itself has uncertainty. Errors always add. Covariance can mitigate, but variance adds! With every correction, the error bars must increase without very strong evidence.

    • “there was a clear warming trend.”

      The question is not if there is a warming trend. At least if you get your science from scientists. The question is (according to the IPCC) if the trend is 4.5C per doubling or 1.5C per doubling. That’s is a big difference. At the moment, it appears theory (models) give higher numbers. This finding lowers observed “real” temperatures where people live, which gives us more certainty that the models are just too sensitive and the warming is less than 3C per doubling. That means a lot when impacts of 3C is unknown, but in the end, we are talking about this not because we disagree on warming or impacts, but because we disagree on climate politics: the amount of money used and how that money is used to tackle climate issues.

      My take is that money is best used to adapt. We can’t stop using energy because that would be an economical disaster, and eventually, a disaster in non-economical terms.

      • There never has been a question about our current warming trend. The questions would be. Is the trend unprecedented or unusual, is the duration long enough to be significant, is the warming trend likely to continue, accelerate or decelerate, and are there any dangers associated with this extent of warming.
        Related questions are. Is the warming caused by humanity and is CO2 the primary driver, and is it necessary, possible, or desirable for warming to be stopped or lessened.
        Clearly the political will for action is evident in only a few jurisdictions and their combined actions are not likely to have a significant effect, if any.
        If someone is a true believer in CAGW, I would suggest they take action to reduce their own vulnerability rather than waste time and energy trying to change the world.

        • Some of the warming is caused by the humanity. More than 50 % since 1950 says the IPCC. Could be near 100 per cent, Gavin says over 100%.

          But even if it is 150%, it appears not to be a reason to panic. Humanity can adapt. It must adapt since we don’t have an ongoing energy revolution. Cheap solar is not here, only worthless solar. And that’s the fact.

    • griff May 3, 2019 at 1:45 am

      Actually griff ,,, it is scientific . Game over

      • I did a study of 2013 records from the CRN top rated US surface stations, as rated by It was published Aug. 20, 2014 at No Tricks Zone. Most remarkable about these records is the extensive local climate diversity that appears when station sites are relatively free of urban heat sources. 35% (8 of 23) of the stations reported cooling over the century. Indeed, if we remove the 8 warmest records, the average rate flips from +0.16°C to -0.14°C. In order to respect the intrinsic quality of temperatures, I calculated monthly slopes for each station, and averaged them for station trends.

        Later I updated that study with 2014 data and compared adjusted to unadjusted records. The analysis shows the effect of GHCN adjustments on each of the 23 stations in the sample. The average station was warmed by +0.58 C/Century, from +.18 to +.76, comparing adjusted to unadjusted records. 19 station records were warmed, 6 of them by more than +1 C/century. 4 stations were cooled, most of the total cooling coming at one station, Tallahassee. So for this set of stations, the chance of adjustments producing warming is 19/23 or 83%.

        • Ron
          Do I understand correctly that your analysis showed greater variance in the high quality stations than those influenced (buffered) by thermal ballast?

          • Clyde, not sure what you mean by “thermal ballast.” It is the case that the well-sited stations records (uncontaminated by UHI) displayed local climate diversity, until of course that was adjusted away.

    • Griff,

      Berkley Earth sorted urban and rural stations by use of satellite measurements of nigh time lights. They provide no information regarding the validity of that means of sorting. For example a temperature station to a building which operates during the day and is closed at night may have few lights a night but would remain a source of man-made heat nonetheless. They concluded from this work that the urban effect is small. What NOAA has shown by running an experiment whereby temperature stations were placed at increasing distances from a known building heat source is that the urban effect is quite large.

      I’ll have to go with NOAA on this one. It seems that Berkley Earth, despite being at a great university, is simply careless.

      • I’ve checked the “night-light” method for Swedish GHCN sites. It’s completely useless. The GHCN coordinates are not nearly precise enough. They can be off by anything up to several kilometers.

        You have to verify the coordinates by actually finding the measurement site on air/satellite photos, plus have access to reliable metadata about site shifts.

      • Berkeley Earth isn’t Berkeley U. Berkeley Earth is an independent non-profit.Note this one donor: Charles G. Koch Charitable Foundation ($150,000)

    • Berkley Earth looked at tens of thousands of weather stations and concluded that …

      Griff – do you have a real study here written by people? If so, cite it. At least give us the year and lead or corresponding author’s name so we don’t get confused with some other Berkley Earth study, of which there are many.

      Why do I suspect “confusing us” is exactly your aim?

    • I live a mile outside of a small 6,000 person rural town. On cold mornings in the winter I’ve seen the temperature 12 degrees Fahrenheit cooler where I live than in town. Yes I’m using the thermometer from my car dash, but it goes up as I go into town and down when I leave town. Most days there is no real noticeable difference but on some of those cold winter days there is a big difference and all that UHI is caused by a small rural town that grew from from 700 people in 1880 to 6,000 today.

      • …and Berkley adjusts 0.2 degrees for UHI

        and get to claim adjustments lower the temp

        • Serious question: Does anyone know what the surface pixel size of the satellite temperature data is? If it is ~100 meters or less (10 ideally), I propose the following experiment: Every time the satellite flies over a weather station (that is not blocked by clouds), the data from the satellite is recorded with the weather station’s temperature, humidity, wind speed and direction, along with the satellite temperature for the pixels going out a kilometer or so. After a while, with variable winds directions and speeds, a good map of the transported UHI heat at various times of day and lighting (or night) conditions would be created that would allow the clever to put the weather station temperature record in much better calibration and context. (I use to work for an organization that was developing space based sub-ten meter multi-spectral imaging sensor.)

      • I agree, but remember…it is the change over time of urban development around a sensor that is key to the ‘trendline’. If the sensor was always there and no further development occurred than we might be able to use its trend with some sort of confidence, but if development increased over time then we cannot have confidence and in most cases, development has increased or sensors were moved etc…

      • My place is about 5 miles northwest as the crow flies from the closest town, which also is a small (less than 5000) country community. Lately, I have been using weather underground for my local forecast. There is a PWS in the town,near thew school complex, and another PWS about a mile due west of me. There is a consistent temperature difference of 3-5 degrees (f) every time I go to the site and toggle between the 2 stations. It should be obvious to anyone open minded that even small rural development has more of an effect on temperature than CO2 ever can.

      • In the Phoenix area in summer nighttime temperatures vary greatly: hot in the metro areas, warm in the desert, and cool in the groves and fields. Placement is everything.

    • I wonder what Berkley Earth and NOAA did differently that the NOAA concluded that temperature trends ARE being distorted. And by that I mean, what did Berkley Earth NOT do that they failed to identify what was going on?

      • See post above….they did not inspect each site’s location directly, they used satellite ‘night light’.

    • Griff, what is it about you acolytes that you insist on lying about what others are saying.
      Nobody is saying that there is NO warming. What we are saying is that the tiny amount of real warming (as opposed to the artificially generated warming) is well within the range of normal and is not in any way dangerous.

      The problems with Berkeley Earth and there well cooked and seasoned books has been documented over and over again.

      • I’ve used this quote from Richard Lindzen innumerable times:

        “Stated briefly, I will simply try to clarify what the debate over climate change is really about. It most certainly is not about whether climate is changing: it always is. It is not about whether CO2 is increasing: it clearly is. It is not about whether the increase in CO2, by itself, will lead to some warming: it should. The debate is simply over the matter of how much warming the increase in CO2 can lead to, and the connection of such warming to the innumerable claimed catastrophes. The evidence is that the increase in CO2 will lead to very little warming, and that the connection of this minimal warming (or even significant warming) to the purported catastrophes is also minimal. The arguments on which the catastrophic claims are made are extremely weak – and commonly acknowledged as such. They are sometimes overtly dishonest.”

        But the marching brooms just pause… and then just keep right on going.

        • Not to hurt anyone’s feelings, including the knowledgeable scientists contributing to this site, but Richard Lindzen, years ago, had already told us everything we need to know about global warming, CO2 and unworkable biofuels, wind and solar. Continuing to beat this dead horse is a gross waste of time and money-including me reading almost every word of every posting on WUWT. I’m retired so me wasting my time on these subjects is no different than reading fiction. But to continue to waste tax $billions studying this “dead horse” and subsidizing building monuments of stupidity: Ethanol plants, wind towers, and solar panels is senseless. I’d love to be wrong. Please tell me any meaningful, significant new finding that disputes Lindzen.

      • His computer likely has an ID-10t operator issue; The IT people tell me that this problem is (after initial investigation) somewhat easy to diagnose, but it is very difficult to correct.

        (they gave up trying to fix mine & told me I just have to live with it.)

    • The “real warming” is more accurately represented by the compliant stations that it is by the non-complaint stations.
      What part of THAT statement do you want to take issue with, Griff?

      The temperatures of non-complaint stations are influenced by their surrounding environment to show a warming trend. This warming trend is of a greater magnitude in non-compliant stations than in complaint stations!
      Once you accept what the data is telling you, then wisdom can find a home between your ears.

    • Actually, Berkeley was rejected because they failed to consider that delta T varies as delta Urbanization.

      Instead Berkeley looked at delta T versus sum(delta Urbanization).

      Berkeley made the classic mistake of comparing acceleration to distance rather than speed and thus missed the correlation.

      When looking for correlations you must consider derivatives and integrals. Otherwise Time can obscure the relationship.

    • Berkeley Earth doesn’t even know to include the resolution limits of the historical instruments. That is a freshman mistake. They are literally inventing data out of thin air.

      Also, the USHCN sensors are unaspirated. Even well-sited stations will have an uncertainty range of about ±0.4 C, because of uncompensated irradiance and wind-speed effects.

      The global average air temperature record is a monument to false precision. The people involved are incompetent.

    • Griff, BEST looked a urban vs. non-urban but many non-urban stations have been effected by artificial changes to the local environment.

    • Griff,

      it appears you forgot a few things, you didn’t post the source, failed to back up your cherrypick claims, not address the post, and that you show no intention to be involved in a meaningful debate with anyone.

      This means you will NOT be missed around here.

    • It’s funny when you call picking unbiased sites “cherry picking.” Also ironic.

    • Berkley Earth looked at tens of thousands of weather stations and concluded that urban heat wasn’t distorting the overall figures and that there was a clear warming trend.

      Thank you, Griff, for demonstrating through your insightful comment that the Berkley Earth analysis is dishonest and not to be trusted.

      I take this message to heart. Although, in truth, it has been demonstrated before, it really must be given even more credence when a catastrophist admits it.

      ===|==============/ Keith DeHavelle (@DeHavelle)

    • Griff

      The UK met office recognises UHI. They make an allowance for it in CEntral England temperature dating to 1659 . The general records they use dating to 1910 Do not allow for it which is why they generally run too high and temperatures break records sometimes

      We are a very small country with 65 million people. Of course millions of buildings and road will make a difference. The impact of UHI was recognised in ancient Rome

  4. It took NOAA long enough, but the wait was worth it.

    Congrats, Anthony, et al.


      • “It is difficult to get a man to understand something, when his salary depends on his not understanding it.”

    • In their defense, to do this study right would take 10 years or more to get enough data to make statistical significance determinations.

      Kudos to them for finally undertaking a real scientific experiment to quantify the effect. I have a feeling this will have to run for quite a while to nail the numbers down with any precision. Also they will probably need to do the same sort of thing for station siting near asphalt paved surface and various field plantings and irrigation setups. (I don’t think doing it for burn barrel positioning is really needed, that one was always one of my favorites.)

      • I don’t think it would take 10 years. If you blanket an area with hundreds of weather stations in a grid, you could quickly piece together the thermal profile of the area. If you do that in several different areas you would learn a lot within a single year. Whether that’s enough may depend on the data.

        Given the stakes and the spending levels being proposed, it’s imperative that such a study be commenced immediately.

        • While qualitatively you can get answers in a year, it really takes all the different seasonal types, complete with rainy years and drought years, El Nino/La Nina years, to quantify how the different weather patterns quantitatively affected the readings.

          Of course if they don’t do that they need to just admit the current database is not fit for the purpose of climate assessment and start over. They probably need to do that anyway. Real adjustments will need real data that is quantified on all the various parameters of a site. Or they can wait for the USCRN to get enough data for climate use and project from there. If the Climate Reference Network is showing less warming, then likely the databases currently in use are wrong.

          • I think after one year you’d have enough to justify a restatement of the data. Another nine years will get you more accuracy, but I suspect you’ll be 90% of the way there after a relatively short period of time.

  5. Anthony looks like vindication to me. And when ever I hear about the “official” adjustments to the temperature record, the adage “figures lie and liars figure” comes to mind. It’s always struck me that you posses that rare commodity “common sense” when you look at the AGW claims. It’$$$ pretty clear who the real “climate denier$$$ are”. I hope you enjoyed that beer, would buy you one if I could.

  6. Anthony, looks like vindication to me. Whenever I hear about the adjustments to the “official” temperature record, the adage “figures lie and liars figure” comes to mind. Wish I could buy you that beer.

  7. Congratulations. Had Anthony Watts and the surfacestations project not highlighted this issue years ago, this would not have happened today. Many thanks.

    • Greg

      I think we have to assume this is true. I don’t see that anyone else has put in the time to make a convincing argument. We realise there were many others participating in the citizen science reassessment of station performance. Absent that, who would have thought NOAA or other highly touted services were not doing their jobs properly, especially something as simple as recording temperatures.

      I tip my hat to all those who literally went the extra mile to examine the condition of these national data-gathering assets.

  8. Good man Anthony! I’ve just put enough for a bottle of “Vin”dication in the top jar. Cheers!

  9. Science 101 , yous means of collecting data must be at least as good as the certainty of the statements you make based on that data.
    Let us be honest and clear for years climate ‘science’ has got away with a ‘better then nothing ‘ standard in various areas such has oceans , proxies , land measurements etc The use of airport based system never intended to be used in this manner being merely on example while ‘magic tree rings ‘ is perhaps both the most hilarious and missed-used . Given the difficulty of accurate weather predictions for years when all of issue where near this did not matter. Now with the claims of ‘settled science’ and the demands based on this claim . This ‘better than nothing ‘ system really is a bloody problem that needs addressing , and so its oddity given the hug sums of money poured into the area and the claims of ‘most important event ever and no time to lose ‘ and the data collection system which really would allow us to understand what is going on , remains a long way below the scientific standard required to take measurements in a meaningful way .

  10. I’ve been following this since the beginning and always knew you were right. I live just outside of a small town and , particularly in winter, when I drive the mile into town the car’s external thermometer always increases by 1 or 2 degrees C. Congratulations.

    • Same for me. I live outside a small rural town. Typically in winter it’s a few degrees Fahrenheit warmer in town than outside of town. I’ve seen it up to 12 degrees F warmer in town than just outside of town on extremely cold winter mornings. Just a small 6,000 person rural town.

  11. very good stuff!

    despite the lack of an x-axis, the trends in Fig4 are also appear interesting – the “pause” and recent downward trends might be worthy of comment….

  12. yup thats vindication in spades!! 😉
    it was damned obvious and your work really showed it up.

    as for griffs comment… facepalm mate! Anthonys proved correct and sometimes you should man up and admit that the clisci mob are WRONG

  13. Surface Station rules! Congratulation. But didn’t adjustments take care of poor locations. LOL

  14. Not so fast

    ‘The impact of the built environment on air temperature diminished with distance with a warm bias only detectable out to tower-B’ located 50 meters away.”

    Now, one major problem with the Le Roy standard that anthony has used is the the Le Roy
    standard ( CRN 1,2,3,4,5) was never FIELD TESTED.

    So now we have a good first test of how far away from a built structure you should be.

    50 meters at least.

    So this is just the beginning. But its good news because the Le Roy standard has never been tested.
    and now it would be a good time to go revist all of the station ratings

      • Sceptical Sam – “And, how many of [Steven Mosher’s] other givens have never been field tested?

        Steven Mosher commented on a recent article here, and in an effort to imply that CO2 can be dangerous at high concentrations, he said water becomes toxic at high concentrations. I’m curious if Steven Mosher is aware of the marine ecosystem.

        • Food is lethal over time if you eat too little or too much.

          We need a food tax to fix this.

          • !!! BREAD IS DANGEROUS !!!
            Research on bread indicates that:

            1. More than 98 percent of convicted felons are bread users.
            2. Fully HALF of all children who grow up in bread-consuming households score below average on standardized tests.
            3. In the 18th century, when virtually all bread was baked in the home, the average life expectancy was less than 50 years; infant mortality rates were unacceptably high; many women died in childbirth; and diseases such as typhoid, yellow fever, and influenza ravaged whole nations.
            4. More than 90 percent of violent crimes are committed within 24 hours of eating bread.
            5. Bread is made from a substance called “dough.” It has been proven that as little as one pound of dough can be used to suffocate a mouse. The average American eats more bread than that in one month!
            6. Primitive tribal societies that have no bread exhibit a low incidence of cancer, Alzheimer’s, Parkinson’s disease, and osteoporosis.
            7. Bread has been proven to be addictive. Subjects deprived of bread and given only water to eat begged for bread after as little as two days.
            8. Bread is often a “gateway” food item, leading the user to “harder” items such as butter, jelly, peanut butter, and even cold cuts.
            9. Bread has been proven to absorb water. Since the human body is more than 90 percent water, it follows that eating bread could lead to your body being taken over by this absorptive food product, turning you into a soggy, gooey bread-pudding person.
            10. Newborn babies can choke on bread.
            11. Bread is baked at temperatures as high as 400 degrees Fahrenheit! That kind of heat can kill an adult in less than one minute.
            12. Most American bread eaters are utterly unable to distinguish between significant scientific fact and meaningless statistical babbling.

            In light of these frightening statistics, it has been proposed that the following bread restrictions be made:

            1. No sale of bread to minors.
            2. A nationwide “Just Say No To Toast” campaign, complete celebrity TV spots and bumper stickers.
            3. A 300 percent federal tax on all bread to pay for all the societal ills we might associate with bread.
            4. No animal or human images, nor any primary colors (which may appeal to children) may be used to promote bread usage.
            5. The establishment of “Bread-free” zones around schools.

        • Have you ever read the Safety Data Sheet for DiHydrogen Oxide? You would never touch another drop of that stuff its so hazardous. Especially dangerous are the acute respirational effects and excessive ingestion leading to the thinning of vascular electrolytes. Bad stuff.

          • Did you know that fresh dihydrogen Monoxide is some 1800% more acidic than sea water !!

    • ‘The impact of the built environment on air temperature diminished with distance with a warm bias only detectable out to tower-B’ located 50 meters away.”

      That is the impact from a building at only one quadrant. What happens when encroachment occurs on one or more other sides, as towns and roads are built? The second parking lot will have less of an impact as the first, but nevertheless, detection of a warming bias well past 50 meters away seems logical. Few stations will be unaffected by UHI bias for 100 years. Anthony has been on the right track all along. There is undoubtedly a warm bias in the official record, probably significant.

      • Great news – well done. I flashed back to the NOAA/NASA warmest year ever press release a few years ago (2015?). The global temp was 0.04C higher, with a 38% probably. One can only imagine how badly located many of the “global sites” used are (and homogenized, pasteurized etc). Surely the location of a sensor could easily result in a 0.04 difference. When records and averages are based on 0.001, 0.01 and 0.10Ts, results and press releases are meaningless. Every government and academic “scientist” should take a course in the climate near the ground based on Geiger’s classic text.

      • Seconding BobM’s observation!

        “This study will have several applied and practical outcomes. Determining the downwind range of influence of a typical building will be important for understanding built environment impacts on surface air temperature measurements.”

        N.B. The picture demonstrates this with a single almost linear line of stations in one direction out of 360+ directions.
        downwind” is only valid when downwind happens to align with USRCRN’s feeble attempt to assess downwind UHI temperature influences.
        An attempt that is so feeble that one can be surprised USRCRN admitted any UHI influences as the research experiment appears to minimize ability to assess downwind exposures.

        Why didn’t NOAA install an array of sensors around their somewhat UHI isolated building? An array that should have thoroughly covered 360° of downwind influences.

        Leaving us with an emphasis upon USRCRN’s “small-scale encroachment on temperature observations”!
        That is; these research observations are strictly for small building complexes.

        Undetermined are those UHI influences for small towns up through urban centers and airports. Small-scale encroachment on temperature observations should be considered the minimum UHI possible.

        These results clarify the need for USRCRN to fully and properly investigate UHI throughout the range of human developments.

        • ATheoK,
          RE: “Undetermined are those UHI influences for small towns up through urban centers and airports. Small-scale encroachment on temperature observations should be considered the minimum UHI possible.”

          As I was reading Anthony’s article and the related posts and comments, I came to the same conclusions that you so succinctly stated above.

    • The Le Roy Standards: Class 1 > 100m from heat sources, Class 2 > 30m

      Class 1 • Flat, horizontal land, surrounded by an open space, slope less than 1/3 (19°). • Ground covered with natural and low vegetation (< 10 cm) representative of the region. • Measurement point situated: o at more than 100 m from heat sources or reflective surfaces (buildings, concrete surfaces, car parks etc.) o at more than 100 m from an expanse of water (unless significant of the region) o away from all projected shade when the Sun is higher than 5°. A source of heat (or expanse of water) is considered to have an impact if it occupies more than 10 % of the surface within a circular area of 100 m surrounding the screen, makes up 5% of an annulus of 10m-30m, or covers 1% of a 10 m circle.

      Class 2 • Flat, horizontal land, surrounded by an open space, slope inclination less than 1/3 (19°). • Ground covered with natural and low vegetation ( 10m, Class 4 “close” to sources, Class 5 everything not included in Class 4…

      So this study shows that even Le Roy Class 2 stations have some warming bias, and Anthony’s study using Class 1 and 2 may be understating the actual bias.

    • Steven Mosher, you’re absolutely correct. Now let’s test the impact of different size communities. If 1 building is 50 meters how about a small 6,000 person community? Or …

      Anyone living in a rural environment knows there’s a significant difference, now let’s put some some numbers to “significant” and apply them to the current stations.

      One thing it does do is prove mankind’s BIGGEST impact on temperature is LAND USE, but adds a series of questions to the science as currently practiced.

      • Exactly. The next phase of study should be to select a test area to blanket with weather stations to measure all those various impacts.

        Politicians are proposing to spend trillions of dollars. Any funds expended here will be money well spent.

    • My understanding is the experiment assessed the presence of a building. Were a big city adjacent to the to the building out of the picture, it would have an effect beyond 50m.

      • Gary
        Yes, Dale Quotrochi (NASA remote sensing scientist) studied Atlanta and found evidence that weather was being affected out to 20 miles (if I remember correctly) downwind. I would guess that the affected distance is proportional to the size of the city, and may vary with the climate.

    • That was a small building and parking lot. Many of the stations are being encroached by much bigger buildings and parking lots, and on multiple sides as well. Many have been surrounded as well.

      The well documented trend difference between stations that actually are well sited vs the rest is well documented and can’t be explained away with your standard wishful thinking.

    • Secondly, there’s a big gap between the second station and the third. 50 meters to 124 meters.

      An honest scientist would say that the difference is not detectable at 124 meters.
      A dishonest scientist would say, as Steve does, that the difference isn’t detected past 50 meters.

    • Now would also be the time to specify the measurement uncertainty at the 95% confidence limit for all stations used all over the world. Now would be the time to demonstrate how these uncertainties would be combined. Now would be the time to include the combined uncertainty in all temperature graphs as upper and lower bounds. Now would also be the time to demonstrate how these uncertainties are calculated and publish the methods for critical examination by other scientists, mathematicians, engineers and metrologists.

    • Mr. Mosher:

      I just wanted to thank you for bringing this NOAA study to Mr. Watts attention. I agree with you that “now it would be a good time to go revisit all of the station ratings”. Also, I agree with Sceptical Sam that it would also be a good time to review all of the assumption that go into the theory of Global Warming.

    • “So now we have a good first test of how far away from a built structure you should be.”

      Certainly, this is just a first step to determining what sort of adjustments need to be made to the data.

      As a first pass, could we simply discard all the data from all the stations that became compromised over time? The difference between the temperature rise of the uncompromised stations and the discarded stations should be close to the average required downward adjustment.

      • I have thought for many years that statistical outliers due to UHI should be removed from the temperature calculations instead of adjusted and subsequently averaged back. There has never been any real attempt to calculate an accurate UHI for any site, only estimates and conjecture. Without a highly reliable downward adjustment, those data points are useless for any purpose. The data points should be excluded from any calculation. Inclusion of any data that is known to be incorrect is poor procedure and produces a specious result. Guessing at an adjustment and then using the data anyway is fraud.

        • I found on the NOAA site, in 2010, information describing how they handle and compensate for what they call “Urbanization Effects.”

          The link I saved is no longer active. I wonder why!

          I wish that I would have captured the text, but assumed the link would be preserved.
          NOAA explained that temperatures which are used (and then called data) go through “several algorithms” to give the results. The algorithms adjusted for population change and some other indirect measurements to improve the data. There was a statement in there that they knew the algorithms worked because the results were what they expected.

          • Send a FOIA (Freedom of Information Act) request to NOAA and they will send you the paper.

          • I found this, Mario. Hope you find it helpful…

            In the fourth paragraph from the top, “urbanization effects” are mentioned. While this is only the “Introduction,” it may provide you with papers/search terms to find out more.


            That Karl guy, as you likely recall, proved to be a shyster. See WUWT articles about him — you can find some by searching for “Karl” in Watts Up With That and the Battle for Science — The First Ten Years , compiled and edited by me and offered as a donation to Anthony to raise money for WUWT and to celebrate in 2016. I don’t think he is making it available anymore — no mention of it or link to it anywhere on WUWT that I could find, so, here is the link to the 2016 page where the pdf is linked to:

            I hope this was helpful. You did ask for Moore help, didn’t you? What??? Oh. (smile)

          • I am looking for the specific article which spoke to several algorithms to give the results. In that article, NOAA explained that they knew the algorithms were correct because the results were as expected.

          • Sorry that wasn’t helpful, Mario.

            When I go to my mom’s apartment where my laptop is, I will use her wifi and try to find that article for you.

            If this thread is closed before I can do that, I will try to find you somewhere else on WUWT.

          • Dear Mario,

            I’m writing this little note to let you know that I’ve tried and tried for hours today here at my mom’s apartment to find that NOAA quote. I can only find related articles and blog entries and some “Page Not Found” Error messages. I’m sorry to disappoint you, but, I am giving up. So bummed… I really wanted to find that for you. Grr. I think I will swear like that old loser, Nye — NOT 🙂

            Rather, I will focus on the positive: I learned quite a bit from all that reading! 🙂

            I hope that all is well with you.


          • Dear Mario,

            I’m writing this little note to let you know that I’ve tried and tried for hours today here at my mom’s apartment to find that NOAA quote. I can only find related articles and blog entries and some “Page Not Found” Error messages. I’m sorry to disappoint you, but, I am giving up. So bummed… I really wanted to find that for you. Grr. I think I will swear like that old loser, N.y.e. — NOT 🙂

            Rather, I will focus on the positive: I learned quite a bit from all that reading! 🙂

            I hope that all is well with you.


          • Dear Mario (P.S. I left a lot out of this third attempt — trying to get past spm bin!)

            I’m writing this little note to let you know that I’ve tried and tried for hours today here at my mom’s apartment to find that quote. I can only find related articles and blog entries and other stuff. I’m sorry to disappoint you, but, I am giving up. So bummed… I really wanted to find that for you. Grr. I think I will swear like that old loser, N-word (heh) — NOT 🙂

            Rather, I will focus on the positive: I learned quite a bit from all that reading! 🙂

            I hope that all is well with you.


    • Now that’s funny. Usually, if necessary, you put lipstick on a pig that is not of your own face. Mosher says “ Not so fast”, then goes on to say positive things about the study. Ergo, lipstick on a pig.

    • Mosher
      Well now, if we take many readings over a long period of time we can add another one or two significant figures and we might well discern an influence (albeit small) out to Station C! After all, what is what is done routinely for reporting global averages. /sarc

    • The time to review the station ratings was long ago when they were chosen as being representative of global trends.

    • That works fine for me. I placed my VPII 300 feet away. The other problem this doesn’t deal with is rapid build out in local cities that become a much larger heat sink than a single building.

    • Unfortunately all we have learned is that an otherwise pristine site needs to be further than 50 metres from any new building. This in no way provides guidance on how much we can rely on any sites that are located near larger build structures, like for example airports, new developments, cities etc. It is likely that the influence is far greater that 50m for larger thermal sinks like airports.
      Attempting to claim that the limit is a minimum of 50m is ignoring the fact that size of the built structure is likely very important.

      What it does say is that there are very few sites that are currently in use that aren’t adversely affected by development.

  15. I will crack a beer in your honour Anthony. You deserve the accolades. Does anyone have a link to the paper…..It is paywalled.

  16. Anthony, congratulations on being totally vindicated!
    You should change “BIG NEWS” in the title to “NO SHIT SHERLOCK!”
    Did they credit you or your work in their study?

  17. Well done Anthony. When will the powers that be start taking an interest in what individual well sited and well maintained temperature recording stations are showing? Mixing junk with good stuff and then using statistics to try and get reliable figures never seemed a good idea to me.

  18. I have always considered this to be very important work, Anthony. I am convinced the global land temperature record has a warming bias, especially when we go back 100+ years since previous studies have shown that the UHI effect comes on the strongest at the start of urbanization.

    • Doesn’t global warming theory say night time temps would increase the most?…

      “Mean aspirated temperature differences were greater during the evening”

      …now, isn’t that convenient

  19. What this suggests to me is that the problem is so complex, with so many variables, that it’s meaningless, or can mean anything you want, which is a shame, considering the $$$$s spent on dealing with the claimed reasons.

  20. It always looked like you were right but to actually have it proven is a big deal.

    Frankly, considering the profile of climate change and the importance attached to temperature trends it looks like you should attract the attention of Oslo.
    But you won’t, of course.

    • MC: I think the elite global gov folk have a lock on the Nobel Committee. Obama got a prize as a bribe to go with totalitarian plans. As it turned out he didn’t need an inducement anyway. But some of the recent clowns and reprobates that have received Nobel Ps have compromised the meaning of it. Greta will get the prize and that will be the final degradation of its value.

      Virtually all universities and scholarship in general has been perhaps irredeemably impaired. We probably need to just make new smaller universities of very high standards and let the rest be starved out.

  21. A beer?
    Never stop at one.
    I’ve bought you a carton.
    Now, what’s next?

  22. Griff,

    Berkley Earth sorted urban and rural stations by use of satellite measurements of nigh time lights. They provide no information regarding the validity of that means of sorting. For example a temperature station next to a building which operates during the day and is closed at night may have few lights a night but would remain a source of man-made heat nonetheless. They concluded from this work that the urban effect is small. What NOAA has shown by running an experiment whereby temperature stations were placed at increasing distances from a known building heat source is that the urban effect is quite large.

    I’ll have to go with NOAA on this one. It seems that Berkley Earth, despite being at a great university, is simply careless.

    • DHR
      Lights make for a good first-order proxy for urban areas, but there are many things that can impact the accuracy. The important actual influences are impervious surfaces, waste heat from cars, heating, and air-conditioning. Humidity plays a role in moderating temperature changes. I have observed that some areas in the mid-west are abnormally bright with lights in areas that are little built up. On the other hand, some suburban areas that are more ‘enlightened’ may work harder at suppressing stray light up into the sky. Older communities tend not to be as well lit along streets as newer ones. There are far too many variables to give credence to lights as being the best indicator of urbanization. I think that a better approach would be the use of GIS shape files that are based on thematic classification of impervious surfaces.

  23. what’s really amazing is that this should surprise anybody with a mind of his own.
    Anybody who ever dealt with temp. measurements knows this problem for years.

  24. Congratulations to Mr. Watts.

    NOAA temperature data for my region clearly show a downward trend in diurnal temperature range over the past century.

  25. This is a huge win by Anthony Watts. It will be interesting to see how Big Green responds as yet another of its lies is exposed.

    • They will handwave it away with “extreme weather”, “polar ice meltdown”, “hottest year EVAH”, SLR “acceleration”, and their latest claim of “species extinction”. Plus others, I’m sure. It’s like playing whack-a-mole with the Climate Liars.

  26. Pardon the following off-topic question, which this temperature-record post suggested to me. It’s about “Steve Goddard’s” data. Obviously, there’s nothing that would insulate those data from the siting-caused reduction in diurnal temperature range to which the head post is directed.

    But does anyone have a good sense of whether those data are what they purport to be: the longest records from US stations that haven’t moved?

    I’m inclined to believe that the data are what Tony Heller says they are. But Mr. Heller’s obvious errors in theory, and his general prickliness, give me pause.

  27. Just a related comment : Isn’t there reason to expect that diurnal-temperature-range reduction can additionally be caused by increased CO2 concentration, independently of siting effects? I.e., wouldn’t CO2’s radiation effects would be more pronounced under low-absolute-humidity conditions than under high ones?

    • DTR would absolutely be impacted by higher CO2. Even by its direct specific heat properties. It is also actually capable of slowing cooling modestly, which keeps moisture in the air longer. This result would be much much more pronounced at night.

      If the site can cool to its baseline over night, though, CO2 will have had no net effect on daytime temperatures. If the site can’t cool to baseline by sunrise, then CO2 will have induced some daytime warming.

      Night time warming, though, is almost exclusively beneficial – loss of dew excepting.

  28. When I came across your station research years ago it was one of the first cracks in my then trust in climate science.

    Nice to see you vindicated.

  29. So far, the adjustments have been the opposite of what they should have been.

    INSTEAD of ‘adjusting’ out the 1-3C differences between urban and rural station data in the latter half of 20th century raw data, agencies like NASA GISS are cooling the past, namely the as warm 1930’s as seen in the US T-max temps in this post. The exact opposite of the adjustments that they should be making to correct UHI caused by urban sprawl. link

    I’m not at all confident that the acknowledgement of UHI will have any effect on the adjustments.

    • “I’m not at all confident that the acknowledgement of UHI will have any effect on the adjustments.” On the adjustments”???? How about on the actual average ADJUSTED temperatures by locale?

  30. It is heartening that NOAA has done this. Now to get the so-called Climate Science community to stop using flawed data, and to stop guessing when there is no data at all because of lack of any temperature records.
    Willie Sing has gone one step further and only uses the highs for well sited rural thermometers. He reports a strong (but not perfect) correlation between TSI (Total Solar Irradiance) and daylight highs. This would indicated that TSI is a large factor, but not the whole picture.

  31. ???? …. how is it that in Wyoming, the good stations are light green, the bad stations are yellow, but the official record is even hotter than the bad stations at orange?

    Trentberth’s missing heat?

  32. Congratulations Anthony. You were right all along and it only took NOAA 15 years to admit it. Surfacestations rules!

  33. So, once all land is developed into civilized structures, will there even be such a thing as a temperature reading not affected by human structures?

    If most of our lives are lived in or in the vicinity of such structures, then isn’t the temperature of interest the temperature in which humans actually live? Non-human-influenced temperatures, thus, become a fantasy, irrelevant to daily life, especially in the range of less than one degree, seemingly.

    • “Isn’t the temperature of interest the temperature in which humans actually live?”

      Yes, but what causes it affects what, if anything, we should do about it.

      Average temperatures may be trending upward in some region, so “planners” conclude that heat-related deaths will become a bigger problem. Because of the reduction in diurnal temperature range, though, summer highs may actually be trending downward.

  34. For the curious, especially those who might wonder what else is close by, and what else the terrain is doing nearby, here is the location of the experiment in Oak Ridge. (35.9832292, -84.2199978)

  35. Nice results 🙂
    It is not enough to know whether a weather station has not been moved or is in a rural environment. What matters is did land use change during it’s operational period. Even a transition from natural to agricultural will rise temperatures. If you search for weather stations with a long track record and always in a natural environment you will notice that it is hard to find a rising temperature trend. As soon a agricultural activity is employed near a station, temperature trends rise. A century ago 70% of land use was natural, today it is about 30% (following a sigmoid like pattern, hint ?). Human activity changes the rate at which moister can be exchanged between soil and air. And thus hindering cooling by convection. Human activity also changes the emissivity of the ground, mostly towards 1 thus capturing more heat. Heat as a product of energy consumption can be neglected.

  36. Vindication for Anthony, acceptance of the true state of land temperature monitoring stations for the scientific community.

    Yes, there’s been warming since the end of the LIA but there isn’t certainty regarding how much since even the “pristine” stations’ data collection has an error range.

  37. It will be interesting to see what adjustments to the data scientists believe are appropriate and whether scientists in other countries will perform similar reviews of their own weather stations.

    If one-third of the warming is attributable to bad data, you can imagine the impact the corrections will have an on all the models.

  38. “increasing distances (4, 30, 50, 124, and 300 m)”

    Idle question. Was there something at 125 meters that caused them to move the sensor 1 meter closer, or is there a mathematical reason for choosing that distance.

  39. So in the distant future climate science and public policy derived from climate science discovers the obvious after years of struggle. How pathetic.

  40. A problem with this finding, though splendid for confirmation of Athony’s work over many years, is that it simply tempts authority to add another set of adjustments & carry merrily on, or certain others to go back to raw measurements & surface station siting records and adjust there.

    I really don’t like data adjustments here, as opposed to limiting records to prisine stations, even if they are few.
    Absent perfect data, thinking about global statements, I would rather deal with to few good data points but generally god data than adjusted data.

    It seem to me that the longest, most accurate record we have of ‘climate’ is the planting & harvest data from around the world….crop selections, yields, last & first frost. We love our proxies where we have no instrument data; why not love them even when we have instrument data. We are not really going to measure anything even to the nearest whole degree with much accuracy, and the temptation to do math on streams of numbers has been the source of much angst.

    Perahaps, as a casual observer I’ve missed the obvious…is anyone running proxies into the present? We often cite agriculture records as evidence of the MWP….how do we compare today? Can we farm in Greenland where the VIkings did?

    • Richard/Anthony,

      Your first paragraph regarding the new NOAA study results justifying
      yet more rounds of sloppy, warm-infested “adjustments” to the record
      is spot on.

      The study results need to be inserted into the Congressional debates,
      even though many “climate emergency” advocates will claim it to be a
      one-off case. Otherwise, we’ll get more of the “nothing to see here”
      comments from the conductors as the climate train keeps on rolling.

  41. Having observed from the air, the boundary of snow/melt to a small community of sparsely built-up semi-rural farms–whilst flying to Toronto one spring–I’d venture the real boundary is further than 50 meters, depending on other conditions.

    • All we can say from this experiment is that for a building/parking lot of this size, the boundary is between 50 meters and 124 meters.
      That we can’t detect a difference at 124 meters is not evidence that the difference stopped at the 50 meter mark. Only someone completely ignorant, or who doesn’t care about telling the truth would make the claim that the affect actually stopped at 50 meters.

      • I 2nd MarkW’s comment. Additionally, there should have been sensors placed all around that building, not just in a line in the direction of average air flow:

        “Mean aspirated temperature differences were greater during the evening (0.47 °C) than day (0.16 °C). This was particularly true for evenings following greater daytime solar insolation (20+ MJDay−1) with surface winds from the direction of the built environment”

        If winds only carried the building’s heat to the sensors 60% of the time, 40% of its influence went undetected.

        This one test is good for confirmation that UHI exists and has affected official temperature records, but does not reveal the full extent of that effect.


        • Indeed, this one good test has shown that UHI is
          a) not zero, and
          b) bigger than hypothesized.
          It does not help estimate a new “adjustment” factor, for there are far too many “degrees’ of freedom to corral any such beast with the limited scientific test they employed.

          It HAS established that ALL UHI correction factors used to date are WRONG. Hopelessly, unrepairably wrong.

  42. How about a UA campus resolution by faculty calling for good science practice and a campus review of how the climate station ended up so poorly sited and ignored and students, faculty, and administrators?

    • Not hard to figure out why. The poor siting helped support the position that the people at NOAA wanted to support. If you look at the downward adjustments to temperature in prior years, it is clear that NOAA has no interest in doing legitimate analysis.

  43. It was Anthony’s case study and findings about disqualifying Stevenson screens siting that convinced me that something was terribly wrong with the early IPCC reports. As I recall, none of some 88 or 89 screens that the IPCC called the best sited screens in the US past siting muster; some were ludicrously sited – nearby A/C, brick buildings, airport taxiway, etc. etc. They had apparently not looked at a one of them. And the warmies call that “science”.

  44. Some basic physics. When water or ice at the interface between air, the skin surface temperature will tend to be the dew point (saturation at 100% humidity). This is true for both evaporation and condensation. Evaporation is endothermic and keeps the surface cool. Hard surfaces such as concrete and asphalt that contain no water or ice heat up during the day and radiate at the higher temperatures. At night, they continue to radiate and that is observed as a temperature drop at the surface. Dew and frost will occur on these surfaces when the temperature gets to the dew point. So the amount of moisture in the air at the surface is controlling the surface temperature at night. The water cycle is controlling the skin surface temperature where water or ice is present, not CO2.

    • Indeed. I noticed that the actual overnight lows were within 1 degree Fahrenheit of the actual dew point at that spot, many years ago, under most actual conditions. You can get evaporational cooling when ground is covered in dew, like it is out here where I am most days, away from big cities, somewhat away from small cities; but suburban by population density; for the first hour or so after sunrise. If it is clear and calm, the greatest drop in temps happen within the last hour before sunset and the first hour afterwards. A graph of the temperature, if done, would look like arterial blood flow. It’d be near the low point for hours, a slow rise then a fast rise, then the rise slows, peaks, slow fall, fast fall, then a slow fall near the trough.

      There is a diurnal variation in the dew point temperature, too. And vegetation matters as well as local water precipitation amounts. Actual skin temperatures vary more than the air temperature does, too. The sun facing side of a metal building can get quite warm, even when the air doesn’t. A metal roof, at/near noon, which is getting about 1KW per m^2 gets *very* hot; enough to thin tar; where I live, from April through September.

      I do wish, though, people would quit talking about IR as if IR is heat. No, IR is light. Internal kinetic energy of a sample of matter is heat. Sure, you can convert one to the other; and back, yet they are *not* the same thing. Energy is energy, but the form matters; since what can be done with one isn’t necessarily what can be done with the other.

  45. Anthony, were you the person who did an experiment comparing the impact of changing from white wash to white latex on temperature stations?
    If I remember correctly the experiment showed that while white was and white latex were equally good at reflecting visible light, white wash was superior at reflecting infra-red.
    As a result stations warmed up by about 0.1C when the white was was replaced by white latex.

  46. You got my PayPal donation as a thank you for your past and present work. The role of citizen science is greatly under rated. You are a credit to the rich tradition.

  47. Heh.
    Anyway, the diurnal variation actually looks more like arterial blood flow than the sawtooth wave depicted; unless other weather factors intervene. It’s a damped-driven system, with multiple causative factors.

  48. So NOAA now is going to adjust the official temperature record downward accordingly, right?
    And they are going to insist on doing the same for temperature records in other countries that have the same siting problems, right?
    And then the lower data is going to be fed into the computer models that project future doomsday predictions for the IPCC, and lower those predictions considerably, right?

    Or is all this just going to be ignored and nothing will change?

    • TD: the same guys adjust all the worlds reporting stations. Interestingly, the actual record highs are in the late 1930s, not just in USA, but Canada, Greenland, Scandinavia and the rest of Europe in the NH, and in South Africa, Paraguay, Ecuador and other locations with long series. Here is one from Capetown that looks like the US raw temperatures:

      It has been adjusted by US and UK fiddlers. See Paul Homewood’s ” Not a lot of people know” website for South American and other similar graphs that must be validation of the US unadjusted longterm set that is now unrecognizable in the fiddled “product”.

  49. Congratulations, Anthony, and thank you for your unrelenting work.

    We know the attacks and insults from the usual suspects will continue but we also know that such parties care primarily about their positions, income and power rather than finding the truth.

  50. Congratulations on showing how the very fundamental measurements used by scientists has flaws!!!!

    Several of us here have been saying over the last several months that the current temperature databases are simply not fit for purpose due to several reasons. My own pet peeve is the treatment of measurement errors or perhaps I should say the lack of treatment of measurement errors. Other physical science scientists such as physicists and chemists would not be allowed to ignore this concept like climate scientists do.

    I think another issue is going to be the use of Tmax – Tmin for daily temperature averages. Some recent comments have convinced me that the increase of averages is occurring because of the increase in night time temps and not daytime temps. I think this is an area ripe for examination. Is it UHI or water vapor or both.

    Lastly, I am old enough to have seen a phenomena out here on the plains where storm fronts follow natural boundaries such as major rivers. They also seem follow man-made boundaries like interstate highways more often than not. In fact, weatherman quite often use the interstates when describing storm tracks. Is this coincidence or anecdotal? Maybe. But if true, I wonder why.

    What all this means to me is that climate scientists have become computer gamers with no interest in doing the physical work to collect real physical data and analyze it from the ground up. All they want is some lowly person to feed them some data that they can massage into whatever virtual world they are creating. This will also let them place the blame on others should their projections be wrong. That isn’t worthwhile science or engineering in my book!

  51. Two conclusions from Leeper et al are interesting:

    “In summary, the field experiment supports the recommendation that air temperature
    observations sites should be located over 100 m from artificial heat sources, which is in line with
    WMO recommendations Leroy 1998, WMO 2014….”

    My memory is that some tiny percentage (2%?) of the stations in Anthony’s Surface Stations project meet that requirement. Here we have NOAA reaching an even more stringent requirement than Anthony himself, who included Leroy Class 2 stations (within 30 m of a heat source) in his paper.

    “Finally, the reported reduction in DTR due to encroachment-1 related warming of
    minimum temperatures is interesting given that climatologically, over the latter half of the 20th
    century, DTR has decreased due to warming minimum temperatures, especially from the 1960s
    to 1980s (Liu et al. 2018, Thorne et al. 2016a, 2016b). Because this is a global signal, seen at
    rural climate stations as well as urban and suburban (Thorne et al. 2016a; Vose et al. 2005; Karl
    et al. 1993), the decrease in DTR has been attributed mainly to non-urban processes (i.e.,
    changes in cloud cover (Xia 2013), precipitation and energy budgets (Dai et al. 1999; Dai et al.
    1997) aerosols (Guo et al. 2017) and others (Kukla and Karl 1993). However, even small-scale
    urban encroachment can result in asymmetric responses between daytime and nighttime air
    temperatures. As a result, DTR and other temperature studies would stand to benefit from the
    availability of land cover and instrumentation metadata. Other observation networks should
    consider USCRN’s practice of taking land-cover photos during annual maintenance visits to
    document changes in station siting.”

    Another common-sense observation, made use of by Anthony’s citizen-science volunteers, but not by those who are maintaining (OK, not actually “maintaining”, just using the data from) the surface station network.

  52. Great news. It makes all of the past effort and expense well worth it. Yes Anthony, you and the rest of us should feel vindicated. Great work and perserverence, but also a sad commentary on the professionalism , or rather lack thereof, in much of the climate science community.

  53. Hats off, Mr Watts – well earned justification!!

    I rather wish I’d kept a diary of my reading and musing about Goebbels Warming – some of the nonsense involved was obvious to my own eyes unprompted. But on some topics – such as the woeful siting of instruments – I needed the help of others. So three cheers for WUWT.

    Hip, hip, hooray. Hip, hip, hooray. Hip, hip, hooray.

  54. Congrats Mr. Watts! But my analytical, conspiratorial mind is spinning with the myriad possibilities of what this NOAA acquiescence might mean.

    I was drawn to your site years ago by (what I considered to be) your rather simple notion that poor (if not intentional) weather station siting was corrupting the climate “warming” data. And in the interim, I’ve learned about temperature “smoothing” and a host of other questionable processes from our highly paid climate “intelligentsia” to explain-away your concerns. I’ve read countless articles that cast aspersions on your science, conclusions, and motives. Never once did these attacks on your character move me. Why? Because the simple LOGIC of your premise, backed up by hard data, made YOUR proposition more believable than your detractor’s beliefs. In fact, the more your detractor’s doubled-down on Watts-HATE … the more believable you’ve become.

    So why now? After ALL these years … has NOAA FINALLY taken your premise seriously? The hopeful, positive, happy side of my brain suggests that the Warmists may be looking for a ‘way out’ of the corner they’ve painted themselves into. That they KNOW the public is fed up with their CAGW ruse, and are looking for a way out of the climate cul-de-sac they’ve driven themselves into. And then the sarcastic, skeptical, realistic part of my brain says HA! What a load of tosh from the ‘happy’ side of my brain. That it is far more likely NOAA is conducting their own ‘Study’ version of your long term Study in order to KILL everything you’ve claimed. But in order to thoroughly KILL it … they must first acknowledge a LITTLE sliver of TRUTH in what you claimed … so they appear unbiased and purely ‘scientific’ in their work. I fear this tiny sliver of agreement will rapidly be followed with the oh so predictable … “but none of this matters, because evil fossil fuels are STILL wrecking the planet”. “Only a worldwide central fascist government imposing communistic control over everyone will ‘save’ the planet from a fiery, hellish demise”.

    All I know is that the pure LOGIC of your initial observations has made me a fan of you and your efforts. I am no scientist, but can claim a rather broad engineering-centric higher education. I suggest it is that educational background which keeps me coming back to read what you, and like-minded people here who are much smarter than I on the topic … to add to my education. Sorry Warmists, I am no slack-jawed yokel from the hinterlands that you imagine every “denier” to be. Wouldn’t it be wonderful if the ‘happy side’ of my brain was right for once?

    • My first thought about this study by NOAA was that they wanted to acknowledge the UHI effect upon the temp record so they could avoid accusations of a cover-up, but designed a test set-up that minimized that effect. This allows them to continue claiming CO2 is causing damage to the climate.


      • Yep. That’s what the logical side of my brain is telling me. Because THAT fits a pattern of behavior by the Warmists

  55. I’m really not sure why we needed a “scientific study” to point out putting a weather reporting station on concrete next to a building isn’t the same as one sited in grass in a rural setting. Anyone with a brain knows you will get two different readings and the urban siting will be warmer than the rural one.

    I guess by how much is of value but even then there are various degrees (no pun intended) of urban and rural placements. Why this is a Eureka moment is beyond me.

    • Climate Science isn’t about right or wrong. It is about proving fossil fuels are evil.

      Not so evil that we make them illegal. Just evil enough that they must be taxed to forgive our sins.

  56. It was about when the Real-Climate-Scientists(tm) started claiming there were no urban heat island or citing effects that they lost the last shred of credibility with me.

    When some is screaming “la la la la CAN’T HEAR YOU” to basic heat transfer equations you realize that their version of the scientific method has gone full cargo cult.

  57. Will they spin this or ignore it?

    I go with “ignore it.” After all, this is just one experiment with only a couple of temperature stations in one location. What does this have to do with “global warming.” Did the world “global” appear anywhere in the paper? Nothing to see here.

    You guys celebrating are very naive. This will change nothing. The AGW people have moved beyond landbased weather stations. Now it is ocean rise and species extinction and melting glaciers and disappearing Arctic ice.

    You don’t understand. This is about money first. Always follow the money. The science does. How many billions of dollars do you control?

    • I think you are correct Joel, the AGW people have moved beyond landbased weather stations….way beyond.

      Think of the fork in the road and the sign indicates one path for low sensitivity (do nothing) on the right and the other for high sensitivity (act now) on the left, which is where we are at…estimates vary, answers not yet available.

      The climate horsey went left years ago. That so many of our educated and elite population bet on this horse and side with Vice President Al Gore’s “settled” narrative is truly remarkable and very difficult to explain.

      Only time will tell

  58. This is great Anthony! Your paper made so much sense, it was hard to believe it garnered no response from NOAA et. al. Not sure what kind of beer you like, but I will tip something malty your way tonight after work.

  59. Would the use of urban heat island stations not further distort the temperature record through the temperature homogenizing process?

  60. As expected, temperature observations were warmest
    BS. UHI has been assumed to be the opposite based on Jones I Lost The Data.

  61. Homogenization has now spread this warming due to urbanization to all stations. Even the most rural have been corrupted by urbanization.

  62. Homogenization has now spread this warming due to urbanization to all stations. Even the most rural have been corrupted by urbanization.

  63. I could use a beer right about now. You can support the work here.

    Done … good sir. Well done!

  64. Next step for the warmists: walk back the anthropogenic attributions. (That retreat will be a lot tougher.)

  65. I wonder if the results of the NOAA study will be reported by the MSM? I doubt it.

    Congratulations Mr. Watts.

    • Yeah, I expect tomorrow’s headline at CNN to be all about the good news that maybe we don’t need to raise taxes or adopt socialism after all!

  66. If the Human race is worried about “Global Warming”, then we should only worry about Avg Max T. If we start worrying about “Global Cooling”, then we should only worry about Avg Min T….IMHO…

  67. Congrats, Anthony.

    I was telling my kids recently that I participated in this study as their science classes were both discussing the impact of cow farts on climate change. I framed it as a lesson to not take anything at face value, and do your own investigation.

  68. warm bias only detectable out to tower-B’ located 50 meters away.
    I fear this will be abused to claim urban site are not affected because they are more than 50 meters away.

    It is faulty reasoning so it is likely to appeal to climate scientists tasked with proving CO2 is the dominant driver of climate.

  69. Please don’t ban Griff as I need an occasional reminder as to why I refuse point blank to go along with the doomsday plant food meme even in polite company as the wife says I should. Meanwhile I’m trying to imagine how the commanding heights Griffs will twist this into an explanation as how the past temps needs coldening even more.

  70. Question: Why were data from such stations used to begin with? There are two responses that I can think of: one is that the people who call themselves scientists were practicing very haphazard, sloppy science, and they didn’t care enough to check their sources; the other answer, the more cynical one, is that they know the flaws of these sites and use them anyway because they yield predictably warmer results, and that allows them to perpetuate an alarmist narrative.

    When “climate scientists” admit there is no mean global temperature for the Earth, let alone an “ideal” temperature (or climate), they’ll have no reason to torture data in the first place.

  71. It was through the surface stations project that I first became aware of this site, and Anthony Watts. I have spread the word about the project as far and wide as my puny contacts will allow. I am a lukewarmer who knows that CO2 should have some impact (no self respecting engineer could say otherwise because H2O and CO2 have to be taken into account for heat transfer calculations within boilers), but knowing what I do about the difficulty with temperature measurements, I couldn’t say by how much the planet has actually warmed. Now I have a reason to suppose it is possibly about one-half as much as NOAA and its various satellite suggest.

    I notice that a lesson many people here are talking about is the effect per distance from structures. I think one should keep in mind that distance per structure is not the whole story, but rather effect per distance from a built-up region. There is a scale size which one must apply to this effect. A large urban area has an effect that often can be observed for kms downwind, even without an individual building within a few hundred meters of the observation.

  72. I think this dilemma partly arose because no one 30 years ago in their right mind could ever have imagined that temperature data would one day be used by political activists to push an agenda. But here we are. If you’re going to use measurements to justify economic and government policy, then at least make sure the data is RELEVANT. Oy vey.

    • Spot on as the move of one of the longest serving Stevenson Screens in the SH in Adelaide South Australia attests. In 1977 the BOM moved it from the West Parklands to their new offices at Kent Town on the eastern side of the CBD ostensibly because it was more convenient to take the manual observations. That would make Anthony’s top rubbish station list particularly as our prevailing winds and weather come from the west and then came automation anyway removing the need for the shift.

      They were building another SC back on the West Parklands so they could get a couple of year’s readings to marry the new Kent Town readings with the old. As if?

  73. I would like to see a REAL study that deals with where to put land based heat detecting measurement devices.

    My first contention is that temperature is not an appropriate measure to use when measuring the heat content of the atmosphere. No one can convince me that the heat content of 98 degrees at 10% humidity in Tuscon, Ariz. is the same as 98 degrees at 80% humidity in Salina, Kansas. Consequently, is pure temperature a useful proxy for heat content? I submit that it is not.

    Once one has decided that heat content is what should be measured, how does one do it? We have both accurate temperature and humidity digital devices. It should not be hard to develop a simple small computer like a Raspberry Pi to combine the two and provide a heat calculation number to transmit.

    With a new device where to site it is a question. If measuring CO2 change to heat in the atmosphere then one needs to find raw undisturbed locations that are totally natural, I wouldn’t think you’d need many. If total heat being added to the atmosphere is what is interesting then put them everywhere even in UHI locations. ICE generates heat, charging batteries generates heat, electric cars generate heat, air conditioners, etc. all generate heat that is added to the atmosphere. If climate scientists and politicians are really worried about artificial heating of the earth, this is what they should be examining.

  74. Years ago at Oklahoma City I participated in a large multi-agency field experiment known as URBAN 2000, where data were collected throughout the citywide area to determine the influence of the urban environment on the properties and movement of chemical plumes there. It might be useful to refer to some of the data with regard to the DTR as well. See:

  75. Did the current paper cite Fall, Watt, and coauthors? The first thing I was taught to do was conduct a literature search of pertinent research. Similar studies were discussed and agreement/disagreement noted. If I disagreed with another set of data, I had to offer a reason why. If I failed to acknowledge earlier work in the field, the paper was considered incomplete.

  76. There are several land use changes that affect the temperature measurements. Both UHI and siting have warming effects. Agriculture/irrigation affects humidity levels which often warm the evenings in rural areas for summer months. And, CO2 probably has a warming influence at night and in the winter. Tough to tease out exactly how much these are influencing GAST.

    When we add in the poor ocean coverage it really does highlight just how much uncertainty exists.

    Related to this topic, I have a theory that the ocean cooling that took place in the 1940s, and was mostly adjusted out of existence, was due to all the ships that were destroyed during WWII. Thousands of them including many oil tankers. How many barrels of oil were spilled into the oceans and might this oil have increased the albedo of the ocean surface and/or prevented deeper penetration of sunlight? Only for a couple of years but that might have been enough to have cut off the warming trend over that period. Thoughts?

  77. I believe that this is a step that NOAA are taking to “cover themselves” in event of a public backlash when eventually common sense prevails and questions are asked as to how the warming trends were calculated. Thanks to Anthony they have finally been pressured to replicate his conclusions.

  78. As an ex yachts person, I LOVE VALENTIA I’m the remote SW Ireland – 120 years record and I think plus 0.43 degs C a century. Untampered

  79. Nice work Anthony, congrats to you and your team for your perseverance!

    I remember reading a discussion over at Real Climate several years ago about the effects of UHI on the temperature record. They were claiming UHI can be ignored because temperature anomaly measurements were not affected by station bias. Does anyone know if this is still being argued by Gavin, Mann and their associates? I completely agree with many others here that at the very least, we should remove all biasing effects on the temp data and then make the calculations.

  80. Report is only based on 5 stations. That’s not exactly a statistically significant sample. Then it talks about the relatively large difference between aspirated and non-aspirated which is a separate issue from distance from a built-up area. What criterion was used to ‘adjust’ historical non-aspirated thermometric data for this effect ? Trend lines of select stations. The possibility for confirmation bias is big. Probably bigger than the high readings given by fast electronic sensors compared to old slow mercury min/max thermometers. Probably more than time-of day readings of old mercury min/max too.

    • I can see all the stations around my city (using WeatherUnderground).

      These are the temperatures being read within 5 miles of my house.

      75, 76, 76, 77, 77, 78, 78, 79, 79, 80, 80

      The spread is just UHI and siting issues.

      I am reading 77 with my own sensors, because I’m just outside of town. Zooming out so I can see 50 miles outside of town, where I know there’s not much development, I see 72, 72, 72, 72, 72, 72, 72, 73, 74.

      Being familiar with the area is critical. The difference can be far more pronounced at night.

  81. Anthony, this is very encouraging! Two decades of simply telling the truth has finally paid its first dividend. A tiny chink has been chipped from the armor of the climate mafia. For the first time in a decade, progress in changing the “official” narrative is evident.

    But there is a larger issue that has yet to be properly addressed. If we are concerned about “climate”, then we must really be focused on the response to specific temperatures and the effects of humidity. The freezing point of water is one obvious discontinuity, and changes in the minimum temperature that fall below this level must have significantly less effect on “climate” than variations in minimum temperatures above this point. And there are important thresholds above this value. Wine grapes, for example, require about 2000 “degree days” to ensure a crop, where the critical value is the positive difference between 55F and the daily maximum temperature. This year in the Puget Sound region, we had, for the first time in the current growing season, about a week of +55F temperatures in early April. Grape vines that had been dormant since last November finally pushed forth some tiny buds. This was followed by two weeks of temperatures that never exceeded 55F, and growth stopped. We’ve now had about two weeks of +55F weather, and the new canes are beginning to grow once more. This is about 3 months later than in the past seven years. We’ve had Februaries that finished with much more growth than we can see in the first week of May. And the reverse temperature sensitivity is probably true if we want to grow huge western cedars such as those that the settlers found in the 1850s. The historical surface temperature records, being nothing more than minimum and maximum temperatures, are useless for such concerns, especially if we are looking at their mean value. And then there’s humidity, which changes the significance of any simple temperature measurement as it modifies the heat content of the air. So the entire focus on an average temperature, approximated as the mid-point between the historical minimum and maximum temperatures is a lot like counting angels on the head of pin. Your critique of the data is entirely correct, and it’s a starting point. But we should question the usefulness this data, even if it had been perfectly measured and recorded, if our concern is understanding the change in climate.

  82. Anthony,
    Congratulations! Your diligent work has illuminated the fundamental flaws in the basic CONUS surface temperature measurement methods and data base. The results of NOAA’s simple experiment confirming your prior conclusions is akin to the ‘unsettling’ tremors that precede a foundation shifting quake! The very flawed foundation for AGW is threatened by peer reviewed NOAA publication. Unsettling science, there’s no denying!

    I discovered WUWT about the time you and a cadre of volunteers were performing USCRN site assessments of USHCN monitoring stations across the USA. The results informed and reinforced my own conclusions that the AGW hypothesis was crippled by many fundamental flaws.

    Thank You! Well Done!

  83. It will be very interesting to see how much media coverage, if any, these findings generate. Given the fundamental nature of the results there should be a great deal of interest from the media, but will that happen in the current frenzy of scare stories?

    The question is how to make the public aware of this paper and its importance.

  84. After seeing the lead picture from UA, Tucson, I understand why someone might think the world is ending. If you stand in a Tucson parking lot in summer, Hell doesn’t seem that far away.

      • Do you know how you can tell if someone is from Phoenix? He is the one that parks at the far end of the parking lot so that he can take advantage of the shade from the light pole.

        When I lived in Phoenix, I’d go for hikes in the desert with my Rhodesian Ridgeback. She’d usually walk about 20 yards out in front of me. There were many times I’d come up over the crest of a hill and find her waiting for me — in the ‘shade’ of a singular saguaro cactus.

  85. So combining the evidence of poor siting,civilization encroachment and the change from mercury in glass to platinum resistor thermometers, we can say what?

    Of temperature today with respect to temperature past?

    I suspect the only answer to “What trend?” is “We cannot say”, based on the inherent error range of the methods used.

    However we can be sure the usual suspects will shriek and fling filth.

  86. One of the articles I remember when I first started visiting this site years ago was Anthony’s pictures of misplaced weather reporting stations. Among the first things we learned in our Air Force Weather Observers training at Chanute AFB was the proper positioning and design for weather reporting stations (must be located in a grassy areas, X number of feet from a building, on flat ground, X number of feet away from concrete and asphalt, X number of feet above ground level, enclosure painted white and so on). The acquisition of good weather data is critical in aviation where false data can lead to immediate threat to life, equipment and property. That so-called weather professionals could be so ham-handed in approach still astounds me. Garbage in, Garbage out. Thank you Anthony for all the good work you do.

  87. Congrats Anthony! It was this UHI-effect you talked about that got me hooked to WUWT, like common-sense trumping “science”.

    The problem with scientist is, they do now a lot about a well-defined field of study with well-defined specialized tools that zoom in on special phenomena within their field. Or stated differently, they know a lot about something that is very small indeed compared to the avalanche of very relevant other things happening all the time in the real world outside their scope.

    So there will always be need of common-sense critique on science, and scientists should welcome it.

  88. Prodding the NOAA into doing this study might save society hundreds of billions of dollars in wasteful spending. Think how many man-years of labor it could be. How many thousands of man-years?

    Not very many people in the history of the world have had as significant an impact as that. Yes Anthony, you deserve a beer.

  89. I live at the edge of city limits. there is a park and golf course between my home and the built up portion of the city. You can feel the temperature drop as you start driving by the golf course. Years ago I installed a weather station with remote temperature sensor. Except on some of the very cold days in winter, the temperature is always at least 2 degrees cooler than the report from the NWS reading at the airport. About 50 miles north of me is a NWS station in a park like setting near a small airport. Twenty-five years ago it looked like the pictures for the ideal station. However today the trees have grown from saplings, about eight feet tall to large stately trees with a canopy protecting the the area from direct radiation of the heat into the atmosphere once the sun sets. Like the area around my house we do not get the dew and frost that develops on the golf course where the area is more open.

  90. At the same time NOAA have been cooling the past temp data to dramatise the global warming meme.

  91. Congratulations Anthony. I’ve been following your studies all these years. I wonder if you or someone can devise a way to better test the pre-WWII annual temperature reductions that NASA, NOAA and others have made. If I’m not mistaken, most all time high temperatures in the United States were recorded in the 1930s and early 1940’s, yet none of those years (after adjustments downward) are in the top 10 warmest years. One would expect a correlation between the all time high temperature records and warmest years , and that correlation existed before the yearly downward adjustments and the encroachment of urbanization which selectively raises night time temperatures more than day time ones.

  92. Anyone with experience in dealing with the data facility in Ashville NC should readily grasp why NOAA is usually the last to recognize self-evident reality.

  93. Yes, I had fun putting together those graphs and maps. But they do not account for CRS bias. The differences are even more stark. Tmean comes in at 0.165C/decade, not 0.204. We take that into account in our upcoming paper.

    We are in the last stages of review by the co-authors before submission. When it’s done, I’ll have a whole new set of maps and graphs for your reading pleasure.

  94. They’ll fix the problem by adjusting the old temperature readings down and the new temperature readings up – that’s their cure for everything. Global warming will be worse than we thought.

  95. They’ll fix the problem by adjusting the old temperature readings down and the new temperature readings up – that’s their cure for everything. Global warming will be worse than we thought.

  96. Anthony, you changed my life some years ago, because you made me consider something that should have been self-evident.

    congratulations. you have been vindicated.

    add to the all of the above, the hyper sensitivity of the new thermometers used in Australia, which JoNova often covers, and you pretty much account for much of the so-called warming, it seems.

    add to that the push to further increase urbanisation over the coming decades by more hundreds of millions and the “alarmists” have pretty much guaranteed a little more warming to fit their narrative, which requires tens of trillions of dollars to “fix”.

    18 Apr: BBC: Climate change: Where we are in seven charts and what you can do to help
    By Nassos Stylianou, Clara Guibourg, Daniel Dunford and Lucy Rodgers
    2. The year 2018 set all sorts of records
    The concern is that such hot and cold weather fronts are being blocked – stuck over regions for long periods – more frequently because of climate change, leading to more extreme weather events…

    (UHI? UHI? UHI?)
    5. Urban areas are particularly under threat
    And it’s the faster-growing cities that are most at risk, including megacities like Lagos in Nigeria and Kinshasa in the Democratic Republic of Congo.
    Some 84 of the world’s 100 fastest-growing cities face “extreme” risks from rising temperatures and extreme weather brought on by climate change…

  97. I recognized the site when I saw the article this morning so I managed a drive by on my way to Oak Ridge today. Located at the intersection of Bethel Valley Road and Scarboro the site is far from level so the out stations are a few feet lower and not visible from the road. It is flanked by ridges on both sides. While the study makes some good inferences it should be set up more carefully and repeated.

    The site is also a few miles downwind from ornl’s Supercomputer center that houses Summit and GAEA.

  98. further “warming” baked in; public to be fleeced to implement the SDGs:

    16 May 2018: UN: 68% of the world population projected to live in urban areas by 2050, says UN
    Today, 55% of the world’s population lives in urban areas, a proportion that is expected to increase to 68% by 2050. Projections show that urbanization, the gradual shift in residence of the human population from rural to urban areas, combined with the overall growth of the world’s population could add another 2.5 billion people to urban areas by 2050…
    The urban population of the world has grown rapidly from 751 million in 1950 to 4.2 billion in 2018…

    Sustainable urbanization is key to successful development
    Understanding the key trends in urbanization likely to unfold over the coming years is crucial to the implementation of the 2030 Agenda for Sustainable Development, including efforts to forge a new framework of urban development…

  99. “As expected, temperature observations were warmest for the site closest to the built environment with an average temperature difference of 0.31 and 0.24 °C for aspirated and unaspirated sensors respectively. Mean aspirated temperature differences were greater during the evening (0.47 °C) than day (0.16 °C). ”

    Very large numbers for the conversation we should be having in this country.

    The people need to hear and understand this.

  100. I live in the country, as opposed to the city. When I drive from the city back to the house in the countryside, I usually experience a drop in temperature. It is usually enough to feel even without looking at the thermometer. Must be a fluke and have nothing whatsoever to do with all of the trees and absence of pavement.

  101. Congratulations Mr Watts !

    Logically, the next steps for NOAA (and other institutions) might (should) be :
    – questioning the “selection” rules of weather stations,
    – questioning the “homogenization” rules of measured data,
    – questioning the several “correction” rules applied to historical data …

    Seems to me that you hit a hell of a shot at the very base of the climatistas’ house of cards 🙂

  102. I used to amaze the folks at the university on summer afternoons by pointing my infra-red thermometer at the parking lot pavement and showing them the readings. UHI has been the golden egg for those who further the alarmist indoctrination and protecting that fragile nugget has been vital. What now can support the claims that the planet warms anywhere besides the poles?

  103. Anthony – it was your examination of biases and siting issues that sucked me in to discussions early on here. You’ve endured a lot of mud slinging and worse. From our small acquaintance, I don’t think ‘smug’ is in your nature, but you should feel very pleased. Vindicated? Yup!

  104. Isn’t the whole point of using temperature anomalies instead of actual temps that they are unaffected by things like site movement, calibrated sensor changes, etc.? There is no need to ever adjust historical data, esp when using anomalies

  105. Congratulations, Anthony! This certainly validates the hard work.

    Now, when do we get to see the official U.S. temperature history get adjusted downward?

  106. I looked through their references, but didn’t see your name, even though you were the prime reference for all of this. You deserve the full credit for this with all the work and sweat you have put into this study.

    I remember when you posted the info the first time. There were over 1,000 “helpful” comments.
    This was the first climate change paper which had public peer reviews. I also remember that peeps got stuck on Time of Observation or whatever the acronym was.
    I assume that all the other earlier papers on global warming used hottest temp + coldest temp for the day, and divided by 2, but you weren’t allowed to do that for some reason.

    Then you posted it again, and I think got another 1,000 comments.
    Hope you can now get this published soon…

    You are our “hero”, when it comes to this information….truth vs fiction.

    • Damn, I tried to donate for a 12 pack for you, but i entered all my VISA debit card info, which was correct, including the security code – everything was OK, but they seem to want me to have a pay pal account…
      I had one maybe 6 years ago… seems you can’t donate unless you have a pay pal account…I know I have donated more recently than 6 years ago…They called me and wanted me to enter a pay pal password, so sorry I just gave up – maybe I’ll try later when I have more time to figure out what they want…sorry.
      I will try and try again…JPP

  107. Nice work Anthony. I like the term “urban encroachment” rather than using “urban heat island”. The former can occur in large and small communities, whereas the latter is usually most pronounced with large cities. It is the changes over time that can have the most impact on trying to assess temperature trends over time. Your study indicates there is an impact in the US on assessing the regional temperature trend.

    The urban encroachment impact is on micro-climates and usually not representative of larger regional and global scales. And yes, micro-climates can be important locally, but these impacts are not caused by increasing CO2 and need to be recognized as separate. Furthermore, these localized impacts need to be removed from global scale assessments if possible, similar to how you removed them from the US regional perspective. Easier said than done, but we have to start somewhere. I would also like to see a Global Climate Reference Network, including ocean buoy sites. A GCRN could easily be funded by a tiny portion of the money being wasted on “green” “renewable” energy.

  108. 27% of land based temp data is in Urban areas so we can eliminate that. Add on all the areas of the world that are estimated including Africa, one fifth of the world’s land mass.

    Not looking good for the alarmist crowd.

  109. Anthony, I remember the big row over your being interviewed on NPR, and the extraordinary intervention by their ombudsman. One of the complaints was that your work had “been invalidated”, etc. I doubt that NPR would dare interview you again, despite these findings, such is the sad state of public discourse these days.

    Oh, and somewhere, I’m sure John V’s head is exploding about now…

  110. About two yeas ago I was walking around the U.C. Berkeley campus with an old childhood friend of mine, whom I learned during our chat was an AGW True Believer, and he actually became angry with me when I expressed some skepticism on the topic. Then we came across an infamous example of one of these now-poorly-sited temperature stations on campus (not by accident — I steered our tour there on purpose). I pointed to it: “Know what that is?” Him: “A beehive?” Me: “No — it’s a temperature-measuring station. Been there since the 19th century.” Him: “Ooooh, wow.” Me (pointing to adjacent building): “And see that vent? It’s the heating exhaust duct for that building, about 25 feet away. Built in the 1960s. Prior to that, this temperature gauge was isolated out in a field. I call it the ‘Urban Heat Island Effect.'”

    Ooooh, boy, did he get mad. He spluttered at first, then fell silent, then broke off the tour and left. Since that time he has never recontacted me. Totally shunned. And yet, I recently went and read his twitter feed, and he STILL rants and raves about Global Warming and fossil fuels. He did NOT learn any lesson.

    As devastating as this new study is, I fear that it will have the same affect on the AGW True Believers as my tour did on my friend — i.e. none. They are way past being affected by evidence and data. It has become a religion.

  111. Rather a large swing from withholding the sites from you at the beginning of surface of station, to this. Congratulations. It’s been a while since you were out in the backyard whitewashing boards and who could have seen how long and how much of you it would take. Thanks for that too.

  112. What is NOAA’s siting criteria ? Shouldn’t everyone one of them be moved off or away from asphalt ?

  113. Anthony Watts, Roy Spencer

    Even if not necessarily agreeing with all results published by, an independent person always enjoys the success of independent volunteers in criticising a major institution, especially when the latter accepts and acknowledges their results:

    And so I do as well.

    But nevertheless, I still have problems with a claim like ‘poor weather station siting leads to artificial long term warming’.

    I tried to compare, by using the ‘GHCN daily’ data set, the data provided by those CONUS stations recognised by as to be ‘well sited’, with all CONUS stations available in the data set. There are in the sum actually a bit over 18000 which were/are active since measurement begin.

    If there is a data set containing a considerable amount of poorly sited stations, then it is GHCN daily!

    I did not find within the exact place for the list of these USHCN ‘sirloin’ stations, and used therefore that communicated by NOAA instead, described there as ‘stations identified as having good siting by the volunteers at’:

    { Should the list contain the wrong station set, so I would welcome the correct one, and would restart the comparison. }

    This file contains a list of 71 USHCN stations. To have the comparison as fair as possible, it was imho better not to use USHCN data, but rather to search for those GHCN daily stations having a perfect match to those found in the ‘set 1’ list. There were 46 of them, visible in a merging of GHCN daily and USHCN station metadata:

    Here is a first comparison of the monthly averaging time series for the 46 stations with the entire set (a mix of daily TMIN, TMAX and TAVG data):

    All anomalies are computed locally for each station; all stations lacking sufficient data for the reference period were rejected (none of the 46 ‘sirloin’ stations was; nearly 8000 were in the full data set).

    Linear estimates, in °C / decade
    – 1900-2018
    – sirloin 46: 0.07 ± 0.01
    – full: 0.03 ± 0.01
    – 1979-2018
    – sirloin 46: 0.21 ± 0.04
    – full: 0.21 ± 0.04

    If you now restrict the comparison to the daily TMINs, you obtain the following graph:

    The best for the end: a comparison of the ‘sirloin’ and the full set with UAH6.0’s monthly time series for CONUS:

    You might reply: OK, but GHCN daily is raw, inofficial data!
    And… you would be right.

    But a worldwide comparison of GHCN daily with GISS land-only looks like this:

    Linear estimates for 1979-2018, in °C / decade
    – GHCN daily: 0.21
    – GISS land-only: 0.22

    J.-P. D.

  114. May I ask , are we just talking about USA weather sites ? Also I am not clear, if the readings are high due to nearby buildings etc.. Will this make any difference to the changes of temps?

    How significant do you think this is to the Global average temp?

    many thanks

  115. May I ask , are we just talking about USA weather sites ?

    While the study appears to be only of US sites, the lessons learned are applicable to any site in the world.

    Also I am not clear, if the readings are high due to nearby buildings etc.. Will this make any difference to the changes of temps?

    Yes. the “urban heat island” (UHI) effect causes temp readings to be higher than they would be absent the influence of the UHI. So if you want a reading that is uncontaminated by UHI, you need to place your sensors far enough away (something greater than 50m) for UHI sources.

  116. Just wondering how much this is news. Some folks commenting seem to be under the impression that UHI has not been considered, analysed and estimated by NOAA etc. But even the paper says that this factor has been addressed by NOAA. This paper is an addition to an ongoing field of study. What impact it will have on the records remains to be seen.

    The UAH temp record for the US shows higher trends than the surface records over the long term, and as I understand it, satellite derived lower trop temperatures are not affected by UHI.

    Anthony, I’ve in the past congratulated you on the surfacestations project where it was used purely for science. Were you really excoriated for it? I seem to remember the criticisms were regarding extrapolating a conclusion about the temp records from a handful of stations early in the project’s history. I followed Mosh and John V (at climateaudit?) as they investigated differences between the official record and different classes of weather stations as your project rated them. Fall et al came out and found similar to the experimental study cited here (min/max bias: low to non-existent diurnal range trend), as well as verified the mean US temperature trend.

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