Re: Is it truth or repeated lies, Letters to the Editor, Burnaby NOW, Nov. 30.
Ziggy Eckardt appears to be claiming the position of local champion of the global warming deniers. Well, that is his choice, and history will judge him for it.
There is no space in one letter to refute all the falsehoods that a global warming denier can pack into one letter. One of the current favourites is "the average global temperature has not budged for the last 14 years." That is an obvious misrepresentation of the actual measurements, as anyone who bothers to look at them will immediately see.
There are many ways of presenting the measurements. Some of them are legitimate; some are not. For example, you could present the actual temperatures. On the other hand, you could choose an arbitrary baseline temperature and then present the temperature differences with respect to the baseline. Both of these methods are legitimate.
Another thing you could do is add annotations right on the temperature graph, and this is often done. For example, there may have been significant volcanic eruptions in certain years, and that would have an impact on the global temperature. Recording that kind of information right on the temperature graph could be very useful in explaining why there are fluctuations in the temperature.
A third thing you could do is use a bar graph as opposed to a line graph. The most common approach is to use a line graph, and then the temperature record looks very jagged. It needs to be understood that the lines themselves do not represent actual temperatures. If the measurements are very close together, then the lines do provide a good approximation to the actual temperature.
No matter how you present the actual data, it's immediately obvious that it's very noisy - there are a lot of fluctuations. This is not at all surprising for a complex system like the Earth. How do you analyze noisy data? Generally, you start by ignoring the rapid fluctuations and looking for the long-term trends.
The most important conclusion available from the entire data set is that the global temperature keeps going up and shows no sign of changing. The second and third most important conclusions are that there are large fluctuations on the 10-year time scale, and that the fluctuations on the one-year time scale are so large that they tell you nothing at all. You need a whole bunch of additional information to try to understand the short-term temperature fluctuations, and for that you definitely have to read the scientific literature.
If you look at the most recent decade, which has been the hottest in all of recorded history, the temperature has not changed much, except for the short-term fluctuations, and may even be going down. Nobody is disputing that point. But to look at only the last decade, and to ignore the evidence from the 120 years before that, is called cherry-picking the data, and it is one of the favorite techniques of the global warming deniers.
Victor Finberg, Burnaby
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