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Climate Change

I need to think carefully about that point. At first blush, I am not convinced of the argument, so rather than dwell on that now, I shall move on. Six conditions need to be met to justify the Government’s proposed action on carbon emissions over the next 40 years. The first is to establish whether the planet is actually warmer, which was what we were just discussing. Establishing that involves considerable measurement problems, but it is clear that the planet has warmed. The Intergovernmental Panel on Climate Change’s median estimate is 0.6 per cent. over the past 100 years, with a margin of error of plus or minus 0.2 per cent. Secondly, it needs to be shown that we are causing that increase. Thirdly, we need to be confident that global warming will continue and that the so-called feedbacks that will come with any change in the temperature will not abate the warming. Fourthly, we need to be clear that by sharply reducing mankind’s carbon emissions, we can secure an arrest or reversal of temperature increases. Fifthly, we need to be sure that the main carbon producers of the world—the UK contributes about 2 per cent. of total carbon emissions—will co-operate and implement massive reductions with us. Sixthly, we need to ensure that the cost of largely decarbonising all the world’s economies is less than the damage that would be caused by a failure to abate carbon emissions. That was the issue raised by the right hon. Member for Oxford, East (Mr. Smith). I intend to consider only the last of those six conditions today, although it is important to bear in mind that they all need to be fulfilled before any country embarks on sharp reductions in carbon emissions. As I have pointed out, several of those conditions might not be fulfilled and, contrary to popular perception, all six are highly controversial. There are strong majority views among experts on some of the issues, but the world of climate science is new and fast-changing and, contrary to what we are often told, there is certainly no consensus on many of those matters.