Introduction:
For over 30 years, I have been giving talks on the science of climate change. When, however, I speak to a non-expert audience, and attempt to explain such matters as climate sensitivity, the relation of global mean temperature anomaly to extreme weather, that warming has decreased profoundly for the past 18 years, etc., it is obvious that the audience’s eyes are glazing over. Although I have presented evidence as to why the issue is not a catastrophe and may likely be beneficial, the response is puzzlement. I am typically asked how this is possible. After all, 97% of scientists agree, several of the hottest years on record have occurred during the past 18 years, all sorts of extremes have become more common, polar bears are disappearing, as is arctic ice, etc. In brief, there is overwhelming evidence of warming, etc. I tended to be surprised that anyone could get away with such sophistry or even downright dishonesty, but it is, unfortunately, the case that this was not evident to many of my listeners. I will try in this brief article to explain why such claims are, in fact, evidence of the dishonesty of the alarmist position.
The 97% meme:
This claim is actually a come-down from the 1988 claim on the cover of
Newsweek that all scientists agree. In either case, the claim is meant to satisfy the non-expert that he or she has no need to understand the science. Mere agreement with the 97% will indicate that one is a supporter of science and superior to anyone denying disaster. This actually satisfies a psychological need for many people. The claim is made by a number of individuals and there are a number of ways in which the claim is presented. A thorough
debunking has been given in the Wall Street Journal by Bast and Spencer. One of the dodges is to poll scientists as to whether they agree that CO
2 levels in the atmosphere have increased, that the Earth has been warming (albeit only a little) and that man has played some part. This is, indeed, something almost all of us can agree on, but which has no obvious implication of danger. Nonetheless this is portrayed as support for catastrophism. Other dodges involve looking at a large number of abstracts where only a few actually deal with danger. If among these few, 97% support catastrophism, the 97% is presented as pertaining to the much larger totality of abstracts. One of my favorites is the
recent claim in the Christian Science Monitor (a once respected and influential newspaper): “For the record, of the nearly 70,000 peer-reviewed articles on global warming published in 2013 and 2014, four authors rejected the idea that humans are the main drivers of climate change.” I don’t think that it takes an expert to recognize that this claim is a bizarre fantasy for many obvious reasons. Even the United Nations Intergovernmental Panel on Climate Change (this body, generally referred to as the IPCC is the body created by the UN to provide ‘authoritative’ assessments of manmade climate change) doesn’t agree with the claim.
Despite the above, I am somewhat surprised that it was necessary to use the various shenanigans described above. Since this issue fully emerged in public almost 30 years ago (and was instantly incorporated into the catechism of political correctness), there has been a huge increase in government funding of the area, and the funding has been predicated on the premise of climate catastrophism. By now, most of the people working in this area have entered in response to this funding. Note that governments have essentially a monopoly over the funding in this area. I would expect that the recipients of this funding would feel obligated to support the seriousness of the problem. Certainly, opposition to this would be a suicidal career move for a young academic. Perhaps the studies simply needed to properly phrase their questions so as to achieve levels of agreement for alarm that would be large though perhaps not as large as was required for the 97% meme especially if the respondents are allowed anonymity.
The ‘warmest years on record’ meme:
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| Figure 1a | Figure 1b | Figure 1c |
This simple claim covers a myriad of misconceptions. Under these circumstances, it is sometimes difficult to know where to begin. As in any demonization project, it begins with the ridiculous presumption that any warming whatsoever (and, for that matter, any increase in CO2) is bad, and proof of worse to come. We know that neither of these presumptions is true. People retire to the Sun Belt rather than to the arctic. CO2 is pumped into greenhouses to enhance plant growth. The emphasis on ‘warmest years on record’ appears to have been a response to the observation that the warming episode from about 1978 to 1998 appeared to have ceased and temperatures have remained almost constant since 1998. Of course, if 1998 was the hottest year on record, all the subsequent years will also be among the hottest years on record. None of this contradicts the fact that the warming (ie, the increase of temperature) has ceased. Yet, somehow, many people have been led to believe that both statements cannot be simultaneously true. At best, this assumes a very substantial level of public gullibility. The potential importance of the so-called pause (for all we know, this might not be a pause, and the temperature might even cool), is never mentioned and rarely understood. Its existence means that there is something that is at least comparable to anthropogenic forcing. However, the IPCC attribution of most of the recent (and only the recent) warming episode to man depends on the assumption in models that there is no such competitive process.
The focus on the temperature record, itself, is worth delving into a bit. What exactly is this temperature that is being looked at? It certainly can’t be the average surface temperature. Averaging temperatures from places as disparate as Death Valley and Mount Everest is hardly more meaningful than averaging phone numbers in a telephone book (for those of you who still remember phone books). What is done, instead, is to average what are called temperature anomalies. Here, one takes thirty year averages at each station and records the deviations from this average. These are referred to as anomalies and it is the anomalies that are averaged over the globe. The only attempt I know of to illustrate the steps in this process was by the late Stan Grotch at the Lawrence Livermore Laboratory. Figure 1a shows the scatter plot of the station anomalies. Figure 1b then shows the result of averaging these anomalies. Most scientists would conclude that there was a remarkable degree of cancellation and that the result was almost complete cancellation. However, instead, one stretches the temperature scale by almost a factor of 10 so as to make the minuscule changes in Figure 1b look more significant. The result is shown in Figure 1c. There is quite a lot of random noise in Figure 1c, and this noise is a pretty good indication of the uncertainty of the analysis (roughly +/- 0.2C). The usual presentations show something considerably smoother. Sometimes this is the result of smoothing the record with something called running means. It is also the case that Grotch used data from the UK Meteorological Office which was from land based stations. Including data from the ocean leads to smoother looking series but the absolute accuracy of the data is worse given that the ocean data mixes very different measurement techniques (buckets in old ship data, ship intakes after WW1, satellite measurements of skin temperature (which is quite different from surface temperature), and buoy data).
