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Guest Post by Willis Eschenbach
Well, I had hoped for the best from BEST, the new Berkeley Earth Surface Temperature project looking at the global temperature record. I was disheartened, however, by the Congressional testimony of Dr. Richard Muller of BEST.
Photo Source He said (emphasis mine):
Prior groups at NOAA, NASA, and in the UK (HadCRU) estimate about a 1.2 degree C land temperature rise from the early 1900s to the present. This 1.2 degree rise is what we call global warming. Their work is excellent, and the Berkeley Earth project strives to build on it.
Human caused global warming is somewhat smaller. According to the most recent IPCC report (2007), the human component became apparent only after 1957, and it
amounts to “most” of the 0.7 degree rise since then. Let’s assume the human-caused warming is 0.6 degrees.
The magnitude of this temperature rise is a key scientific and public policy concern. A 0.2 degree uncertainty puts the human component between 0.4 and 0.8 degrees – a factor of two uncertainty. Policy depends on this number. It needs to be improved.
Why do I think his testimony doesn’t help in the slightest? Well, to start with, I’ve never heard anyone make the claim that the land surface air temperature (excluding oceans) of the earth has warmed 1.2°C since 1900.
Here’s the problem. The actual land surface air temperature warming since 1900 according to the existing datasets is:
NASA GISTEMP: 0.72°C
NOAA NCDC: 0.86°C
So Dr. Muller, in his first and most public appearance on the subject, has made some of the more unusual claims about the existing temperature datasets I’ve heard to date.
1. Since the largest temperature rise in the three datasets is 30% greater than the smallest rise, their work is not “excellent” in any sense of the word. Nor should the BEST team “strive to build on it.” Instead, they should strive to understand why the three vary so widely. What decisions make the difference? Which decisions make little difference?
2. Not one of the three datasets shows a temperature rise anywhere near the 1.2°C rise Muller is claiming since 1900. The largest one shows only about 3/4 of his claimed rise.
3. He claims a “0.2 degree uncertainty”. But the difference between the largest and smallest calculated warming from the three datasets is 0.2°C, so the uncertainty has to be a lot more than that …
4. He says that the land warming since 1957 is 0.7°C. The records beg to differ. Here’s the land warming since 1957:
NASA GISTEMP: 0.83°C
NOAA NCDC: 1.10°C
Note that none of them are anywhere near 0.7°C. Note also the huge difference in the trends in these “excellent” datasets, a difference of half a degree per century.
5. He fails to distinguish CRUTEM (the land-only temperature record produced by the Climategate folks) from HadCRU (a land-ocean record produced jointly by the Hadley folks and the Climategate folks). A minor point to be sure, but one indicating his unfamiliarity with the underlying datasets he is discussing.
It can’t be a Celsius versus Fahrenheit error, because it goes both ways. He claims a larger rise 1900-present than the datasets show, and a smaller rise 1958-present than the datasets.
I must confess, I’m mystified by all of this. With his testimony, Dr. Muller has totally destroyed any credibility he might have had with me. He might be able to rebuild it by explaining his strange numbers. But to give that kind of erroneous testimony, not in a random paper he might written quickly, but to Congress itself, marks him to me as a man driven by a very serious agenda, a man who doesn’t check his work and who pays insufficient attention to facts in testimony. I had hoped we wouldn’t have another temperature record hag-ridden by people with an axe to grind … foolish me.
Perhaps someone who knows Dr. Muller could ask him to explain his cheerleading before Congress. I call it cheerleading because it certainly wasn’t scientific testimony of any kind I’m familiar with. I hear Dr. Muller is a good guy, and very popular with the students, but still … color me very disappointed.
PS – Muller also said:
Let me now address the problem of
Poor Temperature Station Quality
Many temperature stations in the U.S. are located near buildings, in parking lots, or close to heat sources. Anthony Watts and his team has shown that most of the current stations in the US Historical Climatology Network would be ranked “poor” by NOAA’s own standards, with error uncertainties up to 5 degrees C.
Did such poor station quality exaggerate the estimates of global warming? We’ve studied this issue, and our preliminary answer is no.
The Berkeley Earth analysis shows that over the past 50 years the poor stations in the U.S. network do not show greater warming than do the good stations.
Thus, although poor station quality might affect absolute temperature, it does not appear to affect trends, and for global warming estimates, the trend is what is important.
Dr. Muller, I’m going to call foul on this one. For you to announce your pre-publication results on this issue is way, way out of line. You get to have your claim entered into the Congressional Record and you don’t even have to produce a single citation or publish a paper or show a scrap of data or code? That is scientific back-stabbing via Congressional testimony, and on my planet it is absolutely unacceptable.
That is taking unfair advantage of your fifteen minutes of fame. Show your work and numbers like anyone else and we’ll evaluate them. Then you may be able to crow, or not, before Congress.
But to stand up before Congress as an expert witness and refer solely to your own unpublished, uncited, and un-verifiable claims? Sorry, but if you want to make that most public scientific claim, that bad siting doesn’t affect temperature trends, you have to show your work just like anyone else. If you want to make that claim before Congress, then PUBLISH YOUR DATA AND CODE like the rest of us mortals. Put your results where your mouth is, or if not, leave it out of your Congressional testimony. Why is that not obvious?
Anthony’s unpublished and unverifiable claims are as strong as your similar claims. That is to say, neither have any strength or validity at all at this point … so how would you feel if Anthony trotted out his unverifiable claims before Congress to show that Dr. Richard Muller was wrong, and didn’t show his work?
Like I said … color me very disappointed, both scientifically and personally. Dr. Muller, I invite you to explain your Congressional testimony, because I certainly don’t understand it. I am totally confident that Anthony will be happy to publish your reply.
I also urge you to either a) publish the data and code that you think shows no difference in trends between good and poor stations, or b) publicly retract your premature and unverifiable claims. You don’t get to do one without the other, that’s not scientific in any sense of the word.
PPS – Does any of this mean that the BEST analysis is wrong or their numbers or data are wrong or that the BEST folks are fudging the results? ABSOLUTELY NOT. I am disappointed in Dr. Muller’s claims and his actions. The math and the data analysis is an entirely different question. Theirs may be flawless, we simply don’t know yet (nor would I expect to, it’s early days). I look forward to their results and their data and code, this kind of initiative is long overdue.
I want to be very clear than the validity of their actual methods depends only on the validity of their actual methods. The problem is, we don’t even know exactly what those methods are yet. We have rough descriptions, but not even any pseudocode, much less code. Which in part is why I find Dr. Muller’s testimony unsettling …
RELATED: See the rebuttal letter to congress:
UPDATE: in apparent response to Willis Eschenbach, BEST has added this below to their FAQs page. For fairness, I reproduce it here. – Anthony
NEW (4/1) – It appears that in Dr. Muller’s testimony he shows a temperature rise greater rise than others had previously published. Is this so? Can you explain?
The Berkeley Earth plot is for the land data only, since we have not yet begun analysis of ocean temperatures. Because we only analyze land, that was the fair comparison to make. The ocean temperature rise is less, and when included in, it reduces the value of the total temperature rise.
We started with the land data for several reasons:
- It is the data that is affected most by the most contentious issues: data selection bias, urban heat island, and station integrity issues. These are big concerns and we wanted to address them.
- The temperature rise on land is greater than on the oceans, mostly because the ocean distribute the heat over the mixed layer and thereby reduces the temperature rise. Land keeps the heat mostly on the surface. So the land temperature is actually more sensitive to greenhouse gases than is the world temperature.
- The land issue, with 1.6 billion measurements, was a huge one to tackle. It made sense to divide the effort into two stages.
The land only data for the other three groups are available on their websites, and agree with the plot provided in Dr. Richard Muller’s testimony.