Author Stuart D. Jordan responds to critics

The topic of climate change driven by global warming is clearly generating a lot of heat. In reply, it is important to note that my own articles are reports of research performed by thousands of scientists worldwide, whose work has appeared in the peer-reviewed scientific literature. This leads directly into my reply to the first critic.

Mr. Titus claims that there is no evidence that "overwhelmingly presents a conclusion [for, in his words, 'so-called global warming'] that additional research confirms." I believe that, if Titus reads my article carefully in light of the above comment regarding the sources, he might reconsider this view. However, he raises an even more disturbing point when he suggests that scientists should stick to their research and not attempt to assess the most probable outcome of these thousands of refereed studies--which overwhelmingly support the existence of significant recent global warming. Accepting this approach would conveniently serve the interests of those who wish to do nothing to address the problems caused by global warming.

Thomas Gray seems to feel that this refereed worldwide research constitutes "the madness of the crowd" and that the associated climate change is a "popular delusion." That needs no response. However, the expression in his second paragraph, "this scientific controversy," does require one. If Gray can demonstrate that a significant number of active research scientists who publish in the refereed scientific literature have presented convincing evidence for a scientific controversy that calls the current rapid global warming into question, let him present it. Otherwise, one is reminded of the approach of the creationists, who have moved from creation science to intelligent design, and now on to irreducible complexity in their desperate effort to persuade the rest of us that there is a real scientific controversy where none exists. Much of what is written in denial of the recent global warming appears in nonrefereed pamphlets, tracts, and books published by the deniers.

Todd Seavey is correct that current climate models, by which I assume he refers to the so-called General Circulation Models (GCMs), do not deal with the ice ages, but he fails to note that they do not attempt to. The Milankovich effect, thought to be responsible for these large-scale global coolings, is generally not included in the current models, which are dedicated to explaining the variations in the mean global surface temperature over the past one thousand years. For this, the recent climate models have done an admirable job. The comments in his second paragraph suggest that he is noting, correctly, that correlation is not cause; but they also suggest that he has not read carefully the large body of evidence in my article that supports the robustness of the current evidence for climate change.

Alan Cheetham seems to think I have presented "no scientific information." I would suggest that he might reread my article. Perhaps Mr. Cheetham was looking for an original research paper and not a critical review. The rationale for these articles was to present a scientist's perspective on a major scientific problem of genuine concern to all of us. A single research paper could not do that. Cheetham notes correctly that one scientist who analyzed the "hockey stick" made an error in his analysis. However, these data have been reanalyzed, the error has been corrected, and the extremely rapid and disturbing rise in the mean global surface temperature over the last three decades is still there. This is not noted by the critic. He is simply wrong in suggesting that the recent rapid rise is not abnormal when compared to the last one thousand years.

James Libby errs in saying at the outset of his comments that the latest IPCC document "was not written by scientists, but edited by government and NGO bureaucrats." Perhaps he was thinking of the Summary for Policy Makers, which is entirely different. Many terms that he finds offensive are in fact direct quotes one can find in the extensive report I did use, The Scientific Basis. He alludes to "the really serious objections" of the global-warming minimizers and deniers that I do not address. Melting ice caps on Mars is a current favorite. Before any conclusion can be drawn from this work, we would need to consider, among other things, a great deal more of the Martian geohistory than we know today. What we do know is that a postulated increase in solar radiation is not the cause of any recent melting of the Martian polar ice caps. An upper limit has already been placed on recent changes in solar radiation that is far too small to produce the alleged effects. It is also necessary to correct a misconception of some competent meteorologists, of whom the distinguished Richard Lindzen of MIT is mentioned by Mr. Libby. While these scientists are right in noting that models cannot predict what the local weather will be even two weeks from now, climate modeling is quite different. When much longer temporal and spatial scales are involved, boundary conditions are changed and fast, local, large-scale fluctuations damp out rather quickly. Libby's final paragraph offers a flat denial of the evidence for anthropogenic causes of global warming. I recommend my second article to him.