Sir,– Eoin McMahon (November 23rd) criticises your recent Editorial on climate (November 19th) as “alarmist”, claiming that it “regurgitates the increasingly discredited view of the UN’s Intergovernmental Panel on Climate Change (IPCC)”. He also claims empirical evidence indicates that water vapour is having a negative feedback on global warming, and that the main driver of the recent warming was increased solar activity “which is now reversing to a point where there is a significant risk of globally cooler temperatures over the coming decades”.
It is hard to know how to address such bizarre statements, but the following points are relevant: 1. The Intergovernmental Panel on Climate Change (IPCC) has not been discredited.Following the widely-reported “climate-gate” affair, several independent inquiries exonerated the scientists involved, a finding that received a great deal less media attention than the original allegations. 2. The IPCC does not conduct research, it simply collates the latest climate research world-wide. Useful summaries of the findings of climate scientists can be found in a plethora of other outlets, from international science organisations to the annual reports of many national academies of science. 3. Mr McMahon seems to have confused the role of carbon dioxide with that of water vapour. Suffice it to say that there is a great deal of evidence that greenhouse gases such as carbon dioxide have an amplifying effect on warming, while the net effect of water vapour is less clear. 4. There is no evidence of a strong correlation between the warming of recent years and patterns in solar activity.
Like many “sceptics”, Mr McMahon dismisses a link between global warming and an increased concentration of atmospheric greenhouse gases that is strongly supported by multiple lines of evidence, but embraces an alternative theory for which there is no evidence whatsoever. This is not my definition of a sceptic – Yours, etc,