A Bet Won on the Warming Standstill

Congratulations to Dr David Whitehouse of the GWPF for winning a bet with Dr James Annan.

The bet, made in 2007, was that by 2011 that HADCRUT3 temperature record of 1998 would not be beaten by 2011. The bet was made at the instigation of the BBC Radio 4 program “More or Less”. Annan then provided data analysis to show why he was odds-on favourite to win the bet here and here. Both RealClimate and Mark Lynas had earlier weighed in with articles giving the mainstream viewpoint. I post on Dr Annan’s blog the following comment

The mark of good science is not to predict the obvious, but to predict the unlikely.

Dr Whitehouse has stated that it was going beyond the obvious that enabled him to take on the bet. His full analysis can be found at both the GWPF and wattsupwiththat.

Of course there are those who will point to the biased GISSTEMP to show that the warming is continuing. See my analysis here about why that dataset looks to be a little biased. There are of course those who will still maintain the warming is continuing (such as Roger Black of the BBC), but the true measure is the predictive ability.


Show Warming After it Has Stopped Part 2

Last week I posted how Miles Allen had pulled off a trick to show warming in the 21st century after that trend had stopped in 1998. According to David Middleton at Watts up with That, the BBC’s Richard Black is using a similar decadal comparison to show that warming has continued. There are two Richard Black’s claim that the GWPF are cherry-picking the data. First, that an employee of the UK state broadcaster should choose to use a foreign temperature record over the UK one. Second, why the switch to decadal comparisons, when the IPCC has long used the norm.

Let me break this down with two graphs. Like with the previous posting, I see no scientific reason to necessitate why the starting point for the earth’s orbit of the sun has to be on 1st January. I therefore include all 12 month moving averages. That is Jan-Dec, Feb-Jan, Mar-Feb etc. I have also included three lines on my analysis. First the NASA GISSTEMP; second the HADCRUT3 and third the difference between the two.

The first graph shows the decadal change in the NASA GISS figures that Richard Black is talking about. Sure enough the only period where the 12 month average temperature anomaly is lower than a decade before is in 2008. Using the HADCRUT3 data reveals a similar pattern, but the negative period is much longer. If The HADCRUT3 decadal change is subtracted from the GISSTEMP, there is shown to be a greater decadal warming trend in the NASA than in the UK figures. This might suggest the reason for Richard Black’s preference for foreign data over that paid for by the UK taxpayer’s.

The second graph shows the 12 month moving average data – and clearly shows the reasons for both using decadal temperature changes over annual, and foreign data over British. From 1988 to 1997, there was no real warming trend if the Pinatubo cooling is removed from 1995. However the NASA anomaly seems to be around twice as volatile is the Hadley. But in 1998 the position reverses. The natural 1998 El Nino effect is twice according to the British scientists, as it is to Dr Hansen and his team. Post 1998 the story diverges. According to NASA, the warming resumes on an upward trend. According to the Hadley scientists, the 1998 El Nino causes a step change in average temperatures and the warming stops. As a result the NASA GISS warming trend is mirrored by its divergence from the more established and sober British series.

NASA excludes an inconvenient figure on 2010 Temperatures

The NASA Earth Observatory has a nice graph to show average global surface temperatures.

I noticed a small anomaly with the 2010 figures. The blue line, for the British Hadley Centre, appears to be missing.

You can check this by downloading the HADCRUT3 data set from here. Popping these figures into an Excel graph I get the following.

Excel even defaulted to the correct colour! The 2010 average temperature anolmaly on this data set is .468, as against .474 in 2005 and .529 in 1998. This is significant in that the NASA GISS figures show 2010 to be the warmest year on record, something that was pre-announced by leader James Hansen before the year was half way through. Try Googling 2010 Warmest Year on record to see the number of hits. But inclusion of the HADCRUT figures refutes the headline. Statistically it may not be significant, but the headlines show that politically it is important. It is the difference between the claim that global warming stopped in 1998, and that it is continuing.

There is previous form in the climate community, as Steve McIntyre has noted. McIntyre has the following graphic (at page 28 of McIntyre, S. 2008b. How do we “know” that 1998 was the warmest year of the millennium?. Ohio State University Seminar, may 16, 2008.)

As Steve McIntyre states

“In the IPCC Third Assessment Report, they did worse than simply ignoring the problem.

They deleted the declining portion after 1960, thereby giving a false sense of coherence

between the proxies. In AR4, as a reviewer, I asked them to restore the deleted portion.

They refused saying that showing this information would be “inappropriate” (See


IPCC WG1 chapter 6 29 Review Comments) and the downward late 20th century portion

of the Briffa et al 2001 reconstruction was once again deleted in IPCC AR4.”