Published by On Line Opinion 18 January.
A report by the Pew Center on Global Climate Change finds no evidence for fraud or scientific misconduct in the emails hacked from the University of East Anglias Climate Research Unit. To quote the Pew report:
Although a small percentage of the emails are impolite and some express animosity toward opponents, when placed into proper context they do not appear to reveal fraud or other scientific misconduct by Dr. Jones or his correspondents.
An allegation that an analysis was deliberately fudged arises from a misunderstanding. Allegations that data were suppressed are incorrect. Allegations that papers sceptical of climate change were suppressed, and allegations of unethical behaviour, are also not substantiated. The case for human-caused global warming is not significantly undermined.
The Pew Center, located near Washington D.C., is an independent, non-partisan organisation dedicated to bridging among climate science, policy and practical measures. The Pew Center has conducted its own examination of the emails, but official inquiries are also being conducted by the University of East Anglia and by the United Nations. The emails in contention were hacked from the East Anglia unit late last year. From a much larger number of emails, the hackers posted about 1000. Of these perhaps one or two dozen are controversial. Many of those involved the Director of the CRU, Dr. Phil Jones.
Perhaps the most serious allegation has been that an analysis of data was manipulated to obscure an alleged decline in temperature which, it is also alleged, would undermine the case for global warming. Since the emails are private correspondence that are at times terse it is possible to misinterpret them. Based on what was in published papers before and after this email, Pew explains that the data that were allegedly hidden were a particular set of tree-ring data that were inconsistent with actual temperature measurements in the same area, the latter showing no decline. Jones said in an email he had found a trick to hide the decline. As Pew points out, trick is to be interpreted (based on publications) as meaning in this context clever solution rather than devious ploy. Hide the deline is to be interpreted as explain the discrepancy between the tree-ring results and the actual temperature measurements. There was no actual decline to be hidden, and no data were suppressed. It is worth quoting the Pew report in full on this point.
In an email dated Nov. 12, 1999, Prof. Phil Jones stated that he had used a trick to hide the decline. The email does not say what decline he was talking about, so it has been widely misreported that he was hiding a decline in temperatures. Those reports are not correct, nor is it accurate to say that he was actually hiding data, even though he chose the word. The word trick was used as it is in common parlance to mean a clever solution to a problem (e.g., I know a trick to get that stain off your shirt.). The decline he said he was hiding referred to one series of high‐latitude tree ring data from 1960 to 1994 that did not follow measured temperatures at the same locations, even though they had followed measured temperatures for about a century before 1960. That set of tree ring data incorrectly implied a downward temperature trend after 1960. It cannot be said that Jones was literally hiding this fact because two years before he wrote this email he was a co‐author on the first paper to document this divergence issue. That paper, published in Nature in February of 1998, concluded publicly that these post‐1960 tree ring data produce inaccurate temperature estimates. Hence, hiding this decline simply meant following the advice that Jones and colleagues had already aired in the peer‐reviewed literature two years earlier. Many more papers have since been published on the same topic.
So what Jones was referring to was the need to explain why one data set (out of many) that is a proxy for temperature (i.e. tree-ring data) were inconsistent with actual temperature measurements. Subsequent investigation revealed the source of the discrepancy. That is good and proper science. If the data look dodgy for any reason, find out why, and document what you find. If what you find allows, compensate for the problem you have found, though that is not always possible.
Pews interpretation is based on what was published in peer-reviewed papers before and after the email, which make clear what Jones was referring to. It must be remembered that the emails were private correspondence among experts very familiar with the topic and each other, so they are often terse and laden with jargon and colloquialisms.
Regarding the alleged suppression or deletion of data, some of the data the CRU receives may not be publicly released, by requirement of the countries of origin. Some data (about 5%) were deleted in the 1980s from a database collated by CRU staff. The data were deleted because they did not pass quality control processes. The original data, from weather stations, are still available. As Pew notes, the deletion was done at a time before climate became such a politically heated issue, and the scientists did not foresee the need to archive every bit of data regardless of its scientific value. It is not very reasonable to suggest that because the CRU is publicly funded it should have retained every last scrap of data it dealt with even from those less fraught times.
The remaining allegations concern two papers that the correspondents regarded as not having been properly (or at all) peer reviewed before publication, and as having serious flaws, and whether one of the journals involved should be boycotted because it had failed to maintain professional standards. Regarding the first paper, the publisher eventually admitted that the paper should not have been published in the form it was, because its conclusions were not justified by its content. Before he made that admission, he had blocked a restructuring of the editorial board designed to prevent recurrences of the problem, prompting several members of the editorial board to resign, because they did not want to be associated with a journal that was unwilling to maintain professional peer review standards. The second paper was not reviewed at all, and the Editor of the journal (Energy and Environment) openly stated that she was following her political agenda, according to Pew Senior Scientist Jay Gulledge.
The emails include discussion of the possibility of avoiding referring to the two papers and of not submitting papers to the first journal (Climate Research). There is nothing untoward about either suggestion. It is not unusual for scientists not to refer to papers they regard as flawed and they are under no general obligation to (though editors sometimes ask them to do so, and allow them to state their objections). Scientists also send their papers to those journals they consider will give their paper the highest exposure to the relevant audience, and a journals reputation in the field is a normal consideration in that decision.
Potentially of more concern is a discussion of whether the two papers should not be referred to by the IPCC Fourth Assessment Report. The correspondents regarded those papers as deeply flawed. Presumably a line can be drawn somewhere to exclude the most eggregiously flawed or insubstantial papers, particularly if they are not peer-reviewed. There is nothing unethical about the correspondents voicing their opinions and discussing the options. In the end the papers were referred to and discussed in the IPCC report.
The emails also include some impolite language. Science is always contentious, and it is common for scientists in private conversation to use loose and often impolite language regarding some other scientists work. Such behaviour is certainly not confined to climate scientists, nor to scientists in general, as our Prime Minister might attest.
The Pew Center report is written by people who know the field well and are well-qualified to put the emails in context. It is not the last word, the two official inquiries will also report in due course.
At this stage it seems that the allegation of fudging is based on a misunderstanding that is readily clarified by people who know the topic. There was no fudging, there was no hiding of an inconvenient trend, the actual temperature data show there was no trend. The allegations of data suppression and deletion are not supported when the situation is clarified. Regarding alleged attempts to muzzle contrary views, there was robust discussion of whether an improperly refereed paper and an unrefereed paper ought to be referred to in an IPCC report. That discussion was not unethical, and in the end the papers were referred to anyway.
The Pew report points out that the data sets in contention comprise only a very small fraction of data relevant to climate change. They have been reproduced independently by other scientists in other countries who reach similar conclusions. There is a great deal of evidence of many kinds that global warming has ocurred over the past few decades (nine separate lines of evidence are cited). There is also very strong evidence for human dominance of the recent warming. The report highlights three lines of evidence for the latter conclusion.
- Concomitant warming of the troposphere and cooling of the stratosphere (a greenhouse effect signature).
- Without the strong warming effect of human‐induced rise in atmospheric greenhouse concentrations, the observed changes in solar activity over the past several decades would have led to a slight cooling of the Earths surface.
- Climate models reproduce the warming of the past 50 years only when they include the observed rise in atmospheric greenhouse gas concentrations.
Thus there is no basis for claims that the case for human-caused global warming has collapsed, nor that these or any climate scientists have been discredited.