Everyone Freaks Out About Two New Climate Change Studies

New reports on global temperature trends cause a predictable media uproar


How fast is the planet warming? Two new not-yet-peer reviewed studies were published online earlier this week that suggest somewhat different answers. The first agrees with earlier findings about the pace of global warming, while the second argues that half of the recent warming in the U.S. is artificial.**

The first is from the Berkeley Earth Surface Temperature (BEST) project run by physicist Richard Muller. That paper, "A New Estimate of the Average Earth Surface Land Temperature Spanning 1753 to 2011," reported that "the rise in average world land temperature globe is approximately 1.5 degrees C in the past 250 years, and about 0.9 degrees in the past 50 years." The BEST group concluded that the increase in carbon dioxide emissions from humanity was the likely cause of the increase in global average temperature. In its study, BEST claimed to have taken into account "issues raised by skeptics, such as possible biases from urban heating, data selection, poor station quality, and data adjustment. We have demonstrated that these do not unduly bias the results."

At the same time, Anthony Watts and his colleagues published their new study, "An area and distance weighted analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends," which found "for the years 1979 to 2008, yields a trend of +0.155C per decade from the high quality sites, a +0.248 C per decade trend for poorly sited locations, and a trend of +0.309 C per decade after NOAA adjusts the data." The press release for the new Watts study suggests that weather station quality would be a significant issue that undermines the higher global average temperature trends implied by the data reported in Global Historical Climatology Network and in the BEST network.

As is usual in the debates over issues in climatology, the online discussion was measured and polite. Left-wing climate blogger Joe Romm over at ClimateProgress calmly headlined the new BEST study, "Bombshell: Koch-Funded Study Finds 'Global Warming Is Real', 'On The High End' And 'Essentially All' Due To Carbon Pollution." With regard to the new Watts study, the folks over at the right-wing site serenely reported, "New Study Crushes Global Warming Data Claims."

So there you have it—a crushed bombshell!

The Watts study applies a nifty new classification system for the quality of weather station siting devised by French researcher Michel Leroy and adopted by the World Meteorological Association. For example, in order to be considered a class 1 or 2 station no artificial surfaces like parking lots or brick walls must be within 100 meters or 30 meters respectively. Such surfaces spuriously boost the amount of warming that a weather station thermometer would detect. For years, Watts has tirelessly analyzed the quality of weather stations in the United States to identify how their siting might bias their data. In his new study, Watts and his fellow researchers report that U.S. class 1 and 2 weather stations find that temperatures are increasing at a rate of +0.155 per decade in the continental U.S. Poorly sited stations (classes 3, 4, and 5) show a +0.248 per decade trend.

In an email, Watts additionally noted, "We identified the most representative thermometers for climate trend capture are the well sited, non-airport, Class 1 and 2 rural MMTS stations, which have a superior instrument shelter, an electronic memory to capture the high and low, and are removed both from the siting issues as well as urban heat island and airport growth and instrumentation problem effects." Other considerations include alterations to how the land in rural areas [PDF] is used by people. The trend for those stations is +0.032 C per decade. Watts added, "The value is not much greater than zero."

Over the years, the folks at the National Oceanic and Atmospheric Administration have tried to adjust the temperature data from the U.S. Historical Climatology Network to take into account many factors—urbanization, station and instrument changes, airports—that could affect the accuracy of the temperature record. Watts and his fellow researchers claim that while the well-sited stations show an overall trend of +0.155 C per decade and the trend at poorly sited stations is +0.248 C per decade, NOAA adjusts the data so the reported trend is +0.309 per decade. Watts reckons that the problem is that NOAA researchers use temperature data from poorly sited stations to adjust upward the data from the well-sited stations.

"This disparity suggests that a combination of siting issues and adjustments are creating a spurious doubling of the U.S. surface temperature record for the 30 year period of this study," concludes the Watts paper. Via email, Watts generously observes, "I don't believe the errors associated with NOAA adjustments are deliberate, but simply a case of confirmation bias. They expect to find global warming because a popular theory says they should."

Specifically with regard to the BEST study, the Watts study notes, "Given that USHCN [U.S. Historical Climatology Network] stations overlap and are part of the GHCN [Global Historical Climatology Network], the siting issue should be examined for all the GHCN and BEST sites." Translation: The BEST data very likely include a spurious warming trend of which they have not taken adequate account. Via email, Watts also points out that BEST study lumps class 1, 2, and 3 sites together as OK. "Only stations classified as 1 and 2 are acceptable," Watts argues. "I expect that errors such as these have contributed to the failure of all BEST papers in peer review."

Meanwhile, Muller and his colleagues report that their analysis of temperature data shows that the globe has warmed +0.87 degrees C over the past 50 years. Via email, Elizabeth Muller, co-director of Best with her father observes that they "have not looked at the new analysis by Watts in great detail," but add "as near as we can tell we are in agreement with his results. He is critical of our methods, but reached the same conclusions we did—that station quality does not unduly bias the temperature record." When they get around to looking in more detail, they will find that Watts and his colleagues do think station quality problems have in fact significantly biased their temperature records. In any case, Muller notes that an earlier study by BEST analyzed temperature data from only stations that are far from urban areas. "We found that in these very rural areas, there was the same amount of warming as for the global land," she writes.

To get some idea of the magnitude of the trends over which the argument is being conducted, let's do some rough calculations. The BEST trend is +0.87 C over the past 50 years. That implies a temperature increase of +0.174 degrees per decade. The satellite record from the University of Alabama Huntsville researchers John Christy and Roy Spencer finds a per decade increase of +0.14 C. The new Watts study looking only temperature trends for the continental U.S. of +0.155 C per decade.

Admittedly, these very rough calculations are a bit like comparing peaches to nectarines. For example, the satellites measure the temperature of the lower troposphere not the surface. But looking at the Watts study one finds that according to the satellite data, the U.S. tropospheric temperature trend is +0.24 degree C per decade. Watts notes that surface warming is typically amplified in the troposphere by a factor of 1.1 to 1.4, which implies surface temperatures "in the range of 0.17 to 0.22, which is close to the 0.155 degrees C per decade trend seen in the compliant class 1 & 2 stations." (A puzzlement: if Watts' best-sited stations exhibit a trend of +0.032 per decade and the amplification factors are applied, that would imply a U.S. tropospheric temperature per decade trend of +0.035 to +0.045, yet the satellite trend of +0.24 is more than five times that.)

The good news is that both Watts and BEST have been completely transparent about their calculations and their data. This should make it possible for each to check each other's work and get back to the rest of us with their results. They both are aiming to have their work published in peer-reviewed journals as well. In the meantime, I fully expect that the public conversation over climatology will continue to remain as just civil as it always has been.

NEXT: Justice Dept. Responds, Says "Fast and Furious" Report Distorted

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  1. In the meantime, I fully expect that the public conversation over climatology will continue to remain as just civil as it always has been.

    Good one, Bailey.

  2. Yaaaaaawn…I’m gettin’ kinda sleepy from the warmth.

    *lies down to die*

  3. Cue Johnny LTorso in 5, 4, 3, 2….

  4. Ron, I have a question. Whatever the merits of BEST or Muller’s credentials, is it fair to call him a former skeptic? I’ve seen a few things that make it sound like he’s been on the AGW bandwagon for quite some time, though he appears to have called out Mann in the past.

    I ask because much of the media is leading with him being a skeptic who was won over by the science.

    1. PL: My understanding is that Muller was “skeptical” about the magnitude of the global average temperature trend, not about man-made global warming in general. I believe that he was also suspicious about any Climategate number jiggering with respect to temperature trends, so he decided to check himself.

      1. Okay, thanks. Credit to him for not just accepting questionable science. Whether his results are valid is another question of course.

        It frustrates me that he’s being portrayed as some sort of total skeptic who has found the way to the truth, however.

        1. Yep he has been portrayed that way over and over and over. More disingenuity from Team Hot (credit to Epi).

          Once you catch someone in a lie, they are a liar from then on. By lie, I mean calculated attempts to deceive.

        2. Just like any topic, you can’t just lump people into two categories and expect everyone to fit neatly.

          Some non-scientist “skeptics” almost deserve being described by the other term that trivializes genocide. Almost. They know no science and it is largely a political issue to them.

          Most skeptics do not fall into this category and accept one or more of the arguments of the GW believers to some degree. Many, especially those with a science background, are rightly skeptical about how much is AGW as opposed to just GW and about when, if ever, we need to worry about CAGW.

          On top of that you have anyone with any economic sense who knows what types of things are the exact wrong way to try to “fix” it IF CAGW turns out to be a possibility.

          I think Muller has been a scientific skeptic (and as pointed out, worried about the CG1 and 2 e-mails) BUT from some of the statements he’s made, he also sounds like a typical progressive/greenie and made some odd claims that CO2 could be among the worst pollutants and his daughter works as a green consultant pushing govt. funded alternative energy:…..nsultancy/

          He did however almost give Rachel Maddow a stroke the other day when he said the world should move immediately to natural gas obtained via fracking. So he seems reasonable even if he is a bit of a self-promoter.

      2. if his skepticism is a matter of degrees, then calling him a skeptic implies a totally different definition of the word.

        1. I think the point is that he was skeptical of some particular research, not of AGW. However, my kindness ends if he’s going around saying that he had a road to Damascus moment.

          1. Be kind PL. He’s a publicity hound and the Road to Damascus is a great gimick. Let him make some noise about this paper he can’t get published.

      3. Not sure why you think Climategate was about jiggering the instrumental record rather than proxy reconstructions.

    2. Well, it is Richard Muller himself who is saying he is a former skeptic. Skeptics, like Anthony Watts, used to trot out lectures by Richard Muller as proof that there is not certainty to AGW. And I don’t think that the Koch brothers would have funded his research if he did not show at least a little skepticism.

      But he clearly has changed his mind…to the point that he says the IPCC is UNDERSTATED in its warnings. That is probably the more important point to take away from his recent work.

  5. Ron, where’s my credit for coming up with TEAM HOT and TEAM NOT? You big stealer!

    1. It’s with my credit for TEAM BE RULED–in the White House, next to the Nobel Peace Prize and the Winston Churchill bust that absolutely never left ever.

      1. You don’t deserve credit. For anything.

        1. I’ll accept royalties instead, then.

    2. E: All hail to you for the Team Hot and Team Not – take up any objections with the folks from whom I am “borrowing” the image. Also, the word “Team” is suspiciously absent from the image.

      1. Details, schmetails, Ron. So who did you steal it from?

        1. Pirated, not stolen.

      2. Also, the word “Team” is suspiciously absent from the image.

        So you admit you edited the word “Team” out of the image. We have you now, image truth-denier!

  6. Watts reckons that the problem is that NOAA researchers use temperature data from poorly sited stations to adjust upward the data from the well-sited stations.

    “But, let’s be clear, they’re all well intentioned and well meaning people, not shysters.”

    Yeah. They’re just stupid.

    How come only they get to get away with shit like that??? If I tried to do the same thing with my deductions, I would find my ass landing in jail.

  7. The good news is that both Watts and BEST have been completely transparent about their calculations and their data. This should make it possible for each to check each other’s work and get back to the rest of us with their results.

    In the meantime, let’s make a bet on which of the two is insanely jealous enough of the rate of growth of China to not concede any errors from his part?

    Any takers? Hmm?

  8. The BEST trend is +0.87 C per decade [sic] over the past 50 years. That implies a temperature increase of +0.174 degrees per decade.

    Ron, this should say: “The BEST trend is +0.87 C over the past 50 years. That implies a temperature increase of +0.174 degrees per decade.”

    1. Glad someone noticed that. Wish it had been Ron.

      1. Hi all: thanks for the catch – I do note that I mentioned a couple of times that the rate was 0.9 since the 1950s. Still I should always be accurate. Sorry for any confusion. Fixed now.

  9. As is usual in the debates over issues in climatology, the online discussion was measured and polite.

    Which pretty much made Climate Change irrelevant for everybody else.

  10. I fully expect that the public conversation over climatology will continue to remain as just civil as it always has been.

    In all fairness Watts and Muller seem more civil to one another then most climate debates.

    1. jc: That appears to be true, but as examples I did link to some of the other discussants.

      1. In my head I was comparing Watts and Muller to Mann’s and team ad hominem feces flinging at McIntyre every time McIntyre would simply request data.

  11. What would really be interesting is to see temperature rise findings since Mann’s all plotted on a single graph.

  12. Reading a little more, the main difference is not the warming that has occurred so far at a rate of between 0.1-0.2C/decade various estimates from a little google research), but the projections of what will happen in the future (lots of exponential curves highlighted). Everyone seems to be freaking out about runaway greenhouse warming, not a steady increase with counter-feedback mechanisms. So in the end, even if scientists agree on past warming, there’s still plenty of argument about what that means for the future and how that will trend, so panic can remain even if Watts is more correct than Muller.

  13. still not sure why I should care if the earth is getting a little warmer.

    1. Because of the policies it will be used to justify.

  14. How does current climate trends stand out from geologic history?
    Not at all:…..ture=share

  15. I have no idea what side to take. I work in communications (the radio wave kind, not the PR spokeshole kind). We sometimes measure things during test that are the equivalent to 0.1 degree per decade. We call that “data noise” and throw it away with no ill effect.

    You can generate very random numbers using a thermal diode noise source, and find slopes and trends similar to what they are finding in this temperature data, but they don’t mean anything. Truly random numbers will, in fact, appear to cluster and follow trends quite often.

  16. The usual intelligent response from the the GloBULL Warming Hoax Eco-Fascist crowd whenever some objective scientist proves them completely WRONG: LA, LA, LA, LA, LA…we can’t hear you…LA, LA, LA, LA, LA…send us some more taxpayer money for our phony “research”…LA, LA, LA, LA, LA….

  17. CUTE! but no scare quotes?


    “As is usual in the debates over issues in climatology, the online discussion was ”measured” and ”polite”. (scare quotes added by commenter as sarcasm, smile)

  18. One issue that I don’t think has been addressed is that ALL of the temperature measurements regardless of where they are are valid. The difference is that they are only valid FOR THE MICROCLIMATE they represent. If your thermometer is in the middle of NY City then it is representative of that but NOT the rest of NY State. The satellites are measuring all of the US both UHI contaminated sites and those that are not. I would expect them to measure more heat while Watt’s best sites should measure less since he is rejecting those that are exposed to urban environments when he derived the .035 value. Notice that his chart by region shows the NE to have a larger trend which I would conjecture is due to the fact that it is more urbanized and industrialized. I have no idea whether the area of the US encompassed by urban areas would have that large an effect, but I don’t think that has really been addressed.

  19. Curious that all of the aforementioned studies appear to treat climate now, as what’s “normal” which it isn’t, and therefore attempt to attribute changes to what’s changed, which is foolish.

    The average global temperature over the last 570,000,000 years is (given that scale) a virtual straight line 72F, barring the 4 major global freezes. Curiously, it’s currently 56F, as we’re in the midst of coming out of a global freeze. This is due to the closing of the Panama Isthmus, separating the Atlantic from the Pacific, the altered ocean currents triggered a series of ice ages. We’ve just finished number 23, and hopefully that’s it.

    End Part 1

  20. Glaciers, by definition, are formed during an ice age. Similary, by definition, they are supposed to melt after an ice age. Ocean levels have risen approximately 300 feet over the last 18,000 years, and will continue to do so until the previous equilibrium of ocean levels and temperature are reached. Ancient Greek Roman ports are 50-80 feet underwater. Just because man continues to build on an ever changing shoreline does not equate to its my V-8’s fault.

    Current CO2 levels of approximately 395ppmv are at historic lows over the last 570,000,000 years. True that CO2 levels were as low as 150 – 180ppmv during the recent global freeze, but CO2 levels typically drop during such climates. What’s important to know what’s “normal” is to look at the time frame prior to the global freeze. During the 145,000,000 year period prior to this recent 3 million year freeze, CO2 levels averaged between 900 – 3,300 ppmv, peaking as high as 4,000 ppmv. Even evolution proves that plant life is used to much higher CO2 levels. Current plants reach maximum photosynthetic performance when exposed to CO2 in the 1,000 – 1,500 ppmv range. As such genetic preferences adapt over time, the fact that they still prefer a much higher value demonstrates that they previous desired an even much higher amount and have adapted downward. Furthermore, plants that survived were those more adaptable to the current starvation diet levels of CO2.

    End Part 2

  21. Insofar as those professing scientific knowledge of our impending doom, such as famed Hockey Stick graph magician, who professes 560ppmv as a drop dead number, please note that a recent NASA mission concluded that current climate models “vastly overestimate the effect of CO2 on warming,” and “vastly underestimate Earth’s daily heat loss.” I find it laughable that anyone can say any science is settled when they’re proven to be “vastly” wrong.

    End Part 3 of 3

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