A critique of: >Global Warming: >A Boon for Humans and Other Animals* >Thomas Gale Moore >Senior Fellow >Hoover Institution >(Revised February 22, 1995) To be fair to Moore, I feel that I should quote his abstract untouched. Hopefully this will not constitute copyright infringement, as I am reviewing his paper. I am not an atmospheric scientist, but as far as I know neither is Moore. >Abstract > >Contrary to the doom and gloom scenarios that environmentalists >propound, both evidence and theory suggest that global warming would >in general be beneficial for mankind. Simple logic indicates that most >of modern man's activities would be unaffected by warming of 5¡ to 9¡ >Fahrenheit. Agriculture and some services might actually >benefit. Moreover, past history shows two periods that were >significantly warmer than today and during both eras mankind >flourished. The first epoch, which has been dubbed by climatologists >ÒThe Climatic Optimum,Ó brought temperatures which were as warm as the >median prediction for the next century. During this period, Homo >Sapiens shifted from surviving in small tribes through hunting and >gathering to settled farming communities and from the stone age to the >bronze age. During the second warming, ÒThe Little Climate Optimum,Ó >Europe enjoyed the High Middle Ages and went on one of the largest >building sprees ever recorded. This abstract sets out the basic logical fallacies used in Moore's paper. First, there is the argument from personal incredulity ("simple logic" indicates that our infrastructure wouldn't be affected by 5-9 degree warming; i.e. Moore can't beleive that it would be affected). Secondly, there is a mind-numbingly long list of "post hoc ergo propter hoc" stories about how good things happened during warm periods and bad things during cold periods. By picking and choosing from historical occurances, one can try to prove anything, especially when there is no clear causation between the event and what you are trying to prove. For instance, Moore spends a good page or so blaming the Black Death on a cooler climate. While it is tempting to buttress one's theory with an event which killed 1/3 of Europe, a more likely proximate explanation is that caravans of the Mongol Empire, which was at its height at the time, carried plague rats across the steppes from China to Europe (_Plagues and Peoples_, W.H. McNeill, 1977). Cold temperatures may have contributed to lower human disease resistance, but that may not have been a determining factor; cold certainly wasn't necessary for the plague to occur. A representative sample of this type of story-telling is quoted below: >In July of 1789, just prior to the French Revolution, wet >weather and air temperatures between 59 and 85 caused an ergot blight in the r >ye crop of Brittany and other parts of France. This blight caused hallucination >s, paralysis, abortions and convulsions and came after a very cold winter that >had created severe food shortages.209 Obviously, if I went through history looking for examples of cold winters and crop failures, I could find a good many. I daresay that I could come up with an equal number of hot summers and droughts that "proved" that hot weather is bad for people. In terms of historical eras, Moore spends a great deal of time extolling the accomplishments of the High Middle Ages, a warm period. I could just as easily quote all of the accomplishments of the Renaissance to prove that cold periods were better! Finally, Moore ignores almost all of the basis for modern concern about global warming. Scientists are not worried about a "runaway greenhouse" that would destroy society; they are worried about the cumulative effects of rising sea levels, changing weather patterns, and higher temperatures on our physical and ecological infrastructure. Global warming "do-nothingists" like Moore are fond of claiming that we should do nothing about global warming because it would cost 3.5% of our GNP to do so; how much would it cost to counter the effects of warming? Moore doesn't know. Instead, he attempts to reassure us that hunter-gatherer tribes do just fine in warmer areas, as if this has anything to do with the question at hand. Moore's stunning optimism about the low cost of conversion to a warmer climate can be summed up by the quote below: >Scandinavia. The Midwest of the United States was somewhat drier than >it is today, similar to contemporary western Kansas or eastern >Colorado; but Canada enjoyed a warmer climate and more rainfall. So how much will it cost to turn the bread basket of the U.S. into eastern Colorado? Less than 3.5% of GNP? Moore also plays fast and loose with his scientific references in an attempt to gloss over points that he might have trouble defending. An example: >Warmer periods bring benign rather than more violent weather. Milder >temperatures will induce more evaporation from oceans and thus more >rainfall Ñ where it will fall we cannot be sure but the earth as a >whole should receive greater precipitation. Meteorologists now believe >that any rise in sea levels over the next century will be at most a >foot or more, not twenty.2 Here a startling claim (that global climate change would cause benign weather) is camouflaged by being followed by a referenced claim. That rise in sea level will be measured in feet rather than tens of feet has been accepted for some time; that climate change should result in benign weather across the globe has not. Moore himself spares no effort to denigrate existing science: >In fact, the evidence supporting the claim that the earth has grown >warmer is shaky; the theory is weak; and the models on which the >conclusions are based cannot even replicate the current climate. It is This short quotation constitutes such a farrago of misleading half-truths that it is hard to know where to begin in criticising it. First of all, our best models of global climate change predict that observable warming should just now be emerging as a detectable signal from the background climactic noise; scientists don't claim that the Earth has as of yet grown measurably warmer. Second, "the theory" is _not_ weak, there are well-understood reasons based on simple physics why increasing CO2 in the atmosphere should cause the Earth to get warmer. Thirdly, Moore attacks the computer models used in global climate change studies; those models are not necessary in order to "prove" why global warming might occur, they simply attempt to predict the effects of higher CO2 concentration. Their ability to make good predictions is a matter for experts to argue over; even if one supposes that the state of technical development of the models is currently poor, that says nothing about global warming. Like Dixie Lee Ray's work, this is a political tract trying to pass as a scientific one. Thankfully for the state of U.S. scientific education, Moore doesn't have the writing style of Dixie Lee Ray; still I expect that this paper will be picked up and used by those whose economic interests are against sensible precautions regarding global climate change.