Scientific heresy

Now the paragraph goes on to argue that large, net positive feedbacks, mostly from water vapour, are likely to amplify this. But whereas there is good consensus about the 1.2 C, there is absolutely no consensus about the net positive feedback, as the IPCC also admits. Water vapour forms clouds and whether clouds in practice amplify or dampen any greenhouse warming remains in doubt.

So to say there is a consensus about some global warming is true; to say there is a consensus about dangerous global warming is false.

The sensitivity of the climate could be a harmless 1.2C, half of which has already been experienced, or it could be less if feedbacks are negative or it could be more if feedbacks are positive. What does the empirical evidence say? Since 1960 we have had roughly one-third of a doubling, so we must have had almost half of the greenhouse warming expected from a doubling – that’s elementary arithmetic, given that the curve is agreed to be logarithmic. Yet if you believe the surface thermometers (the red and green lines), we have had about 0.6C of warming in that time, at the rate of less than 0.13C per decade – somewhat less if you believe the satellite thermometers (the blue and purple lines).

So we are on track for 1.2C.  We are on the blue line, not the red line.

Remember Jim Hansen of NASA told us in 1988 to expect 2-4 degrees in 25 years. We are experiencing about one-tenth of that.

We are below even the zero-emission path expected by the IPCC in 1990.

Ah, says the consensus, sulphur pollution has reduced the warming, delaying the impact, or the ocean has absorbed the extra heat. Neither of these post-hoc rationalisations fit the data: the southern hemisphere has warmed about half as fast as the northern in the last 30 years, yet the majority of the sulphur emissions were in the northern hemisphere.

And ocean heat content has decelerated, if not flattened, in the past decade.

By contrast, many heretical arguments seem to me to be paragons of science as it should be done: transparent, questioning and testable.

For instance, earlier this year, a tenacious British mathematician named Nic Lewis started looking into the question of sensitivity and found that the only wholly empirical estimate of sensitivity cited by the IPCC had been put through an illegitimate statistical procedure which effectively fattened its tail on the upward end – it hugely increased the apparent probability of high warming at the expense of low warming. 

When this is corrected, the theoretical probability of warming greater than 2.3C is very low indeed.

Like all the other errors in the IPCC report, including the infamous suggestion that all Himalayan glaciers would be gone by 2035 rather than 2350, this mistake exaggerates the potential warming. It is beyond coincidence that all these errors should be in the same direction. The source for the Himalayan glacier mistake was a non-peer reviewed WWF report and it occurred in a chapter, two of whose coordinating lead authors and a review editor were on WWF’s climate witness scientific advisory panel. Remember too that the glacier error was pointed out by reviewers, who were ignored, and that Rajendra Pachauri, the head of the IPCC, dismissed the objectors as practitioners of “voodoo science”.