Many thanks to Jerome Bastien for this response to the John Moore article
It has now become customary for defenders of the theory of anthropogenic global warming (AGW) to resort to ad hominem attacks, arguments by authority, and to set up a number of straw man arguments which are easily and conveniently dismissed. John Moore proved that he is no exception in his piece “Climate skeptic arguments don’t hold ice
However, considering the enormous scale of the sacrifices we have been asked to make based on this theory, a growing proportion of voters are demanding to be convinced by more traditional means, namely empirical evidence. This has caused a problem for the alarmist camp, because such empirical evidence has failed to turn up, despite the billions of dollars thrown into research worldwide. However, before addressing the issue of the missing evidence, let’s address the points raised in Mr. Moore’s column.
First, Mr. Moore lampoons the skeptic side for its use of anecdotal evidence and its cherry-picking of data. So far, I am in full agreement with him. Unfortunately, he then goes on to cite as evidence of global warming the following carefully selected cherries: heat wave in India, drought in the prairies, floods in Manitoba, sea levels in the Netherlands, and the clincher: hockey rinks in southern Ontario.
Clearly, if it is wrong for the skeptic to cherry-pick unseasonably cool temperatures to make its case, it is equally wrong for the alarmist to use unseasonably warm temperatures. As for anecdotes, they have no place on either side of this debate. Anything that smacks “my Manitoba flood trumps your cool summer” is unworthy of a serious debate.
Next, Mr. Moore points to a graph which shows a clear warming trend between 1880 and today. This is his strongest point. What is missing, however, is that this warming trend dates back all the way to the end of the Little Ice Age, i.e. approximately 1850, and that human emissions of CO2 did not become significant until 1940. Moreover, evidence of warming is not evidence of anthropogenic warming (more on this below).
Finally, Mr. Moore turns to argument by authority, citing the disapproval of real climate.org scientists of a suppressed EPA report which makes a coherent case against destroying the world economy in an attempt to solve what may be a nonexistent problem. Specifically, the folks at realclimate.org say of the suppressed EPA report that it is a “ragbag collection of un-peer reviewed web pages, an unhealthy dose of sunstroke, a dash of astrology and more cherries than you can poke a cocktail stick at.” Well, the cocktail stick bit is certainly clever, but it's not an argument.
But seriously, now that we’ve dealt with Mr. Moore’s arguments, I will present at least some of the actual skeptic arguments he purported to address in his column, in the faint hope that he will address them at his next opportunity.
The main argument of the AGW skeptic, and generally of all skeptics, is that there is no evidence. In other words, there is no empirical evidence to support the proposition that human-produced CO2 will cause catastrophic warming. This may come as a shock to some readers, but it is in fact true.
Don’t get me wrong: there is evidence to show the earth is warming, and has been at least since the end of the Little Ice Age. There is also evidence that CO2 is a greenhouse gas. There is also evidence that greenhouse gases warm the earth. From this, the alarmist conclude that more CO2 in the atmosphere will add to the greenhouse effect and warm the earth uncontrollably, glaciers will melt, sea levels will rise, and what is left of humanity will be eking out an existence somewhere in Antarctica.
Except it’s not that simple. CO2 is a greenhouse gas, but as we add CO2 to the atmosphere, the amount of additional heat it absorbs follows a logarithmic curve. In other words, if CO2 levels were to double, the heat absorbed by CO2 would increase but it would not double. Furthermore, CO2 can only absorb infrared radiation at certain wavelengths, and these wavelengths are already almost fully absorbed.
But, the alarmists will retort, the earth is warming! Look at this graph! Yes, the earth is warming and has been since before humans began polluting our atmosphere at an industrial scale. In a system as complex as earth’s climate, there are any number of reasons why the earth may be warming or cooling. Human produced CO2 is certainly a factor which should be examined closely, and it has. But until the link between CO2 and rising temperatures is proven, we must be open to other possibilities. And this link has not yet been proven – in fact, the IPCC’s basis for choosing CO2 as the culprit is so pathetic it’s almost laughable. The following excerpt is taken from the IPCC’s own Fourth Assessment Report (AR4), in section 2.4 titled “Attribution of climate change”:
The observed patterns of warming, including greater warming over land than over the ocean, and their changes over time, are simulated only by models that include anthropogenic forcing.
If you’re having a hard time deciphering what they mean, let me help. The above is weasel-speak for “we cant think of anything else”.
My next point is so obvious I shouldn’t have to make it, but unfortunately I do: computer models are not evidence. Otherwise, dare I say that I have evidence that you can collect gold coins by hitting your head against a brick wall. Yes, I know that climate models are supposed to reflect reality and Super Mario is not. But in order to model the climate accurately we would need to understand the climate system almost perfectly, which we do not. We would need to be able to measure every relevant variable, of which there are thousands, with an accuracy which is beyond our means. Computer models are useful, but they are not evidence.
In order to properly test the theory that increased CO2 leads to catastrophic warming, we need to rely on the good old scientific method, which consists in using the theory to make a prediction, and testing that prediction against observations. If the observations fit the prediction, then the theory lives another day, otherwise, it doesn’t (or at least it shouldn’t). In the case of AGW, the theory predicts that there should be a measurable hotspot in the upper troposphere. Observations from satellites and weather balloons have been made, and no hotspot has been found. In a less politicized field, this would have been the end of it.