Some years back, I believed that man-made global warming (AGW) had been established as firm reality by physical measurements and the application of the laws of physics. I had no reason to believe otherwise - I had read in newspapers that the UN had summarised numerous scientific studies and there was no doubt about the results.
Then I decided to read up on the subject myself and understand what it was all about. With a background in advanced engineering, and experience of statistical analysis in communication systems and modelling a range of physical systems, I had enough background to read and understand what it was all about.
There seemed to be two main themes:
- The global average temperature was rising at an unprecedented rate.
- Rising atmospheric carbon dioxide levels were the cause.
I started to read up about the "hockey stick" graph, famous from its use by Al Gore. Immediately, alarm bells sounded. Most of the graph had been produced by tree-ring temperature proxies. But the last bit, showing rapid temperature rise, had been produced from actual temperature measurements. If you produce a graph where the appearance changes at the exact point where you change the data source, would you have confidence in the graph? Few engineers would.
I quickly came across the work by Steven McIntyre and Ross McKitrick. Quite apart from the question of switching data sources at the crucial point, their work showed that the "hockey stick" graph was based on faulty statistical methods and essentially an artefact of the analysis method devised by Michael Mann. Here was something that just did not make sense - global temperatures have been shown to be rising at an unprecedented rate but the analysis showing this is based on flaky statistical methods?
Then I tried to pin down the physics relating global temperature to atmospheric carbon dioxide. Alarm bells again quickly sounded for me. This conclusion is based on predictions from computer models. Oh - oh... I have enough experience of constructing models of physical systems to know that, even when the physical system is well understood, validating a model so that you can have confidence in its results is very difficult. A model that has not been validated, if you start to believe its predictions, puts you in a far worse position than if you simply say "we don't know".
How can models of the climate be verified, when there are many aspects that are - at best - only partially understood and where observations of the real system are available only for a very brief period? Even more alarm bells rang for me when I read the UK Met Office's statements that their climate models are verified by checking that they correctly reproduce the historical data used to construct them. For any engineer who has constructed models of engineering systems, such a statement is a joke (a bad one). If a model cannot even reproduce the data used to construct it, then it is clearly worthless - but reproducing the training data is far from confirming that the physical model is correct and will produce reliable predictions.
Then I found that things were even worse yet. To predict significant warming based on increased carbon dioxide, the models incorporate positive feedback effects, where the effect of carbon dioxide is assumed to be multiplied by a large factor. Any engineer who has had to cope with the ticklish instability of systems incorporating large amounts of positive feedback has extreme difficulty believing that planet Earth's climate incorporates significant positive feedback.
By this point, I had become a sceptic of AGW. It seemed to me that there were elements of religious belief in its proponents ("knowing" a thing to be true, even in the absence of evidence). They were talking the talk of science - but walking the walk of a new religion.
Yet, how was it possible that the UN's Intergovernmental Panel on Climate Change could present all this stuff as "rigorous science"? I had the beginnings of an understanding of this question towards the end of 2009, when I downloaded and read the "Climategate" emails. It was very clear that IPCC lead authors had been conspiring to keep out anything that cast doubt on the AGW orthodoxy.
I have greatly enjoyed reading Donna Laframboise's book "The Delinquent Teenager Who Was Mistaken for the World's Top Climate Expert." It explains in detail how all this nonsense has been passed off as rigorous science by the IPCC.
My question now is this: What were all the other journalists of the world up to while this was happening? There were enough clues that something very wrong was going on.