A friend recently loaned me the DVD of “An Inconvenient Truth” featuring Al Gore, the politician-turned-environmentalist who was beaten to the White House by George Bush.
The film was so full of half-truths that it is difficult to know where to start. One example will suffice. Al Gore cited the drying up of lake Chad as a result of Climate Change. It so happens that I spent three months flying light aircraft around Lake Chad in 1978. This was right at the end of a period of global cooling that took place between (roughly) 1960 - 1980 The level of the lake had been falling for years. There is not the slightest evidence that this had anything whatsoever to do with climate change. It might, but it seems unlikely.
But Gore’s biggest error was the classical one beloved of politicians, and the media: he confuses a positive correlation with a causal relationship. The issue is not whether the climate is changing, nor whether Carbon Dioxide concentrations in the atmosphere are increasing, nor whether mankind’s activities are putting out Carbon Dioxide.
The point at issue is the linkage between these observations. Has the carbon dioxide caused the warming, or has the warming caused the carbon dioxide? Or are they both related to something else like sunspots, cloud cover or factor X that we haven’t discovered yet?
There is no “safe side” to this argument. If mankind’s activities are indeed the cause of climate change then Gore’s conclusions are correct (even if his arguments aren’t) and we should be putting our energies into curbing emissions. But if they are not, then carbon capture, carbon trading and all the rest are a dreadful waste of money and energy that we should be putting into safe drinking water supplies, irrigation, storm warning systems and flood defences.