By now, many readers of this page have probably read about "climategate"--the controversy over thousands of hacked emails that appear to reveal a conspiracy among climate change researchers to marginalize those that disagree with them and even manipulate data to support their points.
Others, particularly Reason's science correspondant Ron Bailey, are much more versed in this issue on the technical merits, but I believe a couple of issues are worth emphasizing. First, Ken Green from the American Enterprise Institute has an excellent article discussing the meaning of these revelations for the scientific community. Writing for the Frontier Center for PUblic Policy, Ken points out that the most troubling aspect of this behavior is the intentional actions of leading climate "scientists" to marginalize the legitimate research of those that might come to different conclusions. Notes Green:
"Finally, and most troubling, are the suggestions that a tribe of incestuous climate scientists may have actively conspired to undermine the peer-review process.
The climate change industry, along with people like Al Gore have slammed skeptics for not publishing in the peer reviewed literature. What the Climategate documents reveal is that this small group of scientists, who often peer-review each other's work as well as skeptical articles, have discussed ways of keeping findings they don't like out of the peer-reviewed literature as well as the IPCC reports, even if it required trying to oust editors, boycotting certain journals, or to reclassifying a prestigious journal that publishes skeptical articles as a fringe journal unworthy of consideration. They also discuss their specific intention to exclude contrary findings from the IPCC reports, even if they "have to redefine what the peer-reviewed literature is!"
A more scientifically provocative article (in my opinion) appeared in the Wall Street Journal on Monday by MIT professor Richard Lindzen. Rather than focus on the behavior of the scientists, Lindzen assesses the weak and highly uncertain nature of the data and methods used by climate scientists to reach their conclusions and the way this information is handled in the media. According to Lindzen:
The IPCC's Scientific Assessments generally consist of about 1,000 pages of text. The Summary for Policymakers is 20 pages. It is, of course, impossible to accurately summarize the 1,000-page assessment in just 20 pages; at the very least, nuances and caveats have to be omitted. However, it has been my experience that even the summary is hardly ever looked at. Rather, the whole report tends to be characterized by a single iconic claim.
The main statement publicized after the last IPCC Scientific Assessment two years ago was that it was likely that most of the warming since 1957 (a point of anomalous cold) was due to man. This claim was based on the weak argument that the current models used by the IPCC couldn't reproduce the warming from about 1978 to 1998 without some forcing, and that the only forcing that they could think of was man. Even this argument assumes that these models adequately deal with natural internal variability—that is, such naturally occurring cycles as El Nino, the Pacific Decadal Oscillation, the Atlantic Multidecadal Oscillation, etc.
Yet articles from major modeling centers acknowledged that the failure of these models to anticipate the absence of warming for the past dozen years was due to the failure of these models to account for this natural internal variability. Thus even the basis for the weak IPCC argument for anthropogenic climate change was shown to be false.
Of course, none of the articles stressed this. Rather they emphasized that according to models modified to account for the natural internal variability, warming would resume—in 2009, 2013 and 2030, respectively.
But even if the IPCC's iconic statement were correct, it still would not be cause for alarm. After all we are still talking about tenths of a degree for over 75% of the climate forcing associated with a doubling of CO2. The potential (and only the potential) for alarm enters with the issue of climate sensitivity—which refers to the change that a doubling of CO2 will produce in GATA. It is generally accepted that a doubling of CO2 will only produce a change of about two degrees Fahrenheit if all else is held constant. This is unlikely to be much to worry about.
Yet current climate models predict much higher sensitivities. They do so because in these models, the main greenhouse substances (water vapor and clouds) act to amplify anything that CO2 does. This is referred to as positive feedback. But as the IPCC notes, clouds continue to be a source of major uncertainty in current models. Since clouds and water vapor are intimately related, the IPCC claim that they are more confident about water vapor is quite implausible.
There is some evidence of a positive feedback effect for water vapor in cloud-free regions, but a major part of any water-vapor feedback would have to acknowledge that cloud-free areas are always changing, and this remains an unknown. At this point, few scientists would argue that the science is settled. In particular, the question remains as to whether water vapor and clouds have positive or negative feedbacks.
At the end of the day, I think climategate reflects the weakness of climate science, the big personalities and careers of those involved, and the inherent weakness of the media to really understand (let alone respect or communicate) the complexities of the phoneoma being studied.
For those interested in an excellent, extensive and largely objective summary of climate science from the point of view of global warming sceptics, I highly recoommend the Heartland Institute's recent book Climate Change Reconsidered.