Ex climate sceptic' Muller's latest BEST stuff is the worst so far
Non-partisan' group abandons pretence of neutrality
Posted in Energy, 31st July 2012 10:14 GMT The Register
Analysis Richard Muller's Berkeley Earth Surface Temperature (BEST) project, which began with goodwill from all corners of the climate debate, has made a series of bold announcements (without benefit of peer review) to the effect that global warming is definitely serious and definitely caused by humans. This has aroused derision among formerly supportive climate sceptics, caused an eminent climatologist to abandon the project, and even drawn criticism from generally alarmism-sympathetic media commentators.
Muller, professor of physics at UC Berkeley, is often regarded as a climate sceptic because he has frequently criticised the techniques used by climate scientists in the past and because he accepted funding for BEST from libertarian oil billionaire Charles Koch. When BEST launched in the wake of Climategate, it vowed to be "an independent, non-political, non-partisan group", with Muller promising that "there will be no spin, whatever we find". Critics of the existing temperature establishment, including well known sceptics Anthony Watts and Doug Keenan, welcomed it.
BEST renewed its science-by-release offensive last week, including an ambitious assertion that Prof Muller could attribute warming to the specific cause of carbon emissions by curve fitting (capturing the trend in the data by assigning a single mathematical function across the entire range).
Now an independent expert who peer-reviewed one of the four new BEST journal submissions has published his comments. The BEST team stated that the paper had not been rejected by peer review and no major flaws had been discovered. This does not appear to be true: the Journal of Geophysical Research ended up rejecting the BEST paper on UHI (Urban Heat Island) effects.
Last September, Ross McKitrick - an associate professor of economics - was asked by the geophysical research journal to review the BEST heat-island paper, which had been submitted to the journal. McKitrick is the economist whose statistical analysis, with Steve McIntyre, of a well-publicised temperature reconstruction led to Congressional hearings in 2006. These hearings endorsed McKitrick and McIntyre's work and raised serious questions about the conduct of the paleoclimate science community.
McKitrick was asked last year to review BEST's approach to grappling with the UHI (Urban Heat Island) effect. It's fair to say he wasn't impressed.
McKitrick said he had discovered "serious shortcomings" in BEST's methods and said "their analysis does not establish valid grounds for the conclusions they assert." He continues: "I suggested the authors be asked to undertake a major revision."
The second comment is worth taking the time to read, as new research using a much more comprehensive classification system puts the lack of rigour in dealing with the UHI effect in the spotlight. BEST appears to replicate the lack of rigour, and worse, appears not to care overmuch:
In their Journal of Geophysical Research submission, the BEST team writes:
"We are not asserting that surface temperature data are unaffected by urbanization, but that a global average based on data that includes stations that may have warmed due to urbanization is not significantly different to one based only on stations that are assumed not to contain urban effects."
McKitrick comments, rather acidly:
I suspect that any reasonable reader, upon completing the paper, would be startled to learn that the authors did not intend to assert that surface temperature data are unaffected by urbanization. I think the above sentence was meant to say something like: “We are not claiming there are no contaminating influences in individual locations, only that they are too small and isolated to affect the global average.”
Unfortunately the whole issue is whether their methodology reliably supports this conclusion, and in this draft they have done nothing to deal with the evidence that it does not, instead they simply assumed the problems away.
Muller also made the claim that he was a former climate skeptic, which was rapidly disputed.
"If [Al Gore] reaches more people and convinces the world that global warming is real, even if he does it through exaggeration and distortion — which he does, but he’s very effective at it — then let him fly any plane he wants," Muller told climate activist website Grist in October 2008, rather undermining his claim to be sceptical or even impartial at that point.
All this leaves much of the press, including the New York Times - which indulged Muller by giving him an op-ed space last week to announce his latest results - with some explaining to do.
This seems to have been acknowledged even by the New York Times Malthusian-in-Residence, Andy Revkin, a very widely read environment columnist who is generally sympathetic to the warmist position. Revkin wasn't impressed with the Mullers' "PT Barnum showmanship".
Meanwhile, the most distinguished co-author of the early BEST papers last year has declined to be involved in the latest. Dr Judith Curry, Professor and Chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology and President of Climate Forecast Applications Network (CFAN), describes the work as "oversimplistic and not at all convincing in my opinion".
There's a critical analysis by two early participants in BEST, writing in a personal capacity, on Curry's blog, here.
The BEST team uses some interesting techniques, such as kriging – estimating values at locations which haven't been sampled by using a weighted average of neighbouring samples to estimate the 'unknown' value at a given location, so named for geostatistics pioneer Danie Krige – to compensate for sampling biases in station coverage.
The team also examines more stations than existing temperature series. However, BEST fails to use the latest, and more comprehensive, WMO standard for station quality, which results in low quality data. And it's limited, by design, to ignore satellite and sea readings – thus ignoring most of the Earth, which is mostly covered by water.
All in all, it would seem that BEST's stated goal - to produce absolutely undisputable climate data and science, for all that this would mean a regrettable absence of simple, clear soundbites - has been abandoned.
Post a Comment