Christopher Booker on climate science: comment and conjecture, but where are the facts?
Another Monday, another article from Christopher Booker containing some choice snippets of misleading information on climate science.
As we seem to write almost on a weekly basis about scientific inaccuracies in Booker’s articles, it’s worth noting that the only defence that the Telegraph have for publishing this sort of misleading material is that it is classed as ‘comment’. Therefore (in the opinion of the Press Complaints Commission) it is excluded from the normal requirements of not being “misleading” or “inaccurate”, because the article just reflects Booker’s views.
The PCC Editors’ code of practice states:
“The Press, whilst free to be partisan, must distinguish clearly between comment, conjecture and fact.”
It seems to us that there might be a difference between an article in which, for example, someone suggests a politician is an idiot – (that’s clearly comment) – and an article in which someone makes a series of basically inaccurate statements about scientific research. But maybe we’re old fashioned.
Perhaps Christopher Booker’s bylines should clearly state that his articles are purely comment and conjecture? This week, he asserts that:
“The global warming scare has not continued to unfold as projected by those bent computer models on which it rested.”
And continues:
“Temperatures have not risen as predicted, the ice caps aren’t melting, nor sea levels rising, nor hurricanes, droughts and heatwaves intensifying as we were assured they would.”
As always, Booker doesn’t provide any references to support his assertions, so we are left guessing at where he gets his information. His sources certainly don’t seem to include peer-reviewed scientific literature, as a quick check reveals that Booker’s claims are, once again, unfounded and inaccurate.
So…
Global warming has not stopped
Booker starts by echoing the current favourite skeptic meme:
“Temperatures have not risen as predicted”
This argument usually relies on considering a short sample of temperature data – and in climate terms, 15 years would fall within the definition of a short sample, as Peter Stott of the Met Office explains:
“Fifteen years is just too short a period over which to measure climate change […] The world undergoes natural temperature changes on all kinds of time scales from daily variations to seasonal ones. It also varies naturally from year to year and decade to decade.”
So it’s fair to say that temperatures have risen as predicted, pauses and all. Short-term pauses in the surface temperature record are not unusual in the historical record, and do appear in climate model simulations of man-made greenhouse gas increases.
Furthermore, this argument relies on considering only surface temperature records, and ignoring the oceans completely. In fact, even when short-term fluctuations give rise to pauses in the surface temperature record, warming continues in the deep ocean.
Ice caps are melting
As we have discussed before, Booker’s claim that the “the ice caps aren’t melting” is straightforwardly wrong.
Arctic sea ice is in decline, and at a faster rate than can be simulated by the climate models used in the IPCC 2007 report. The world’s major ice sheets – covering Greenland and the Antarctic – are also losing mass, and that this ice loss has been getting faster.
Only Antarctic sea ice is growing, thought to be due to changes in how heat circulates in the ocean and changes in the atmosphere caused by ozone loss above Antarctica. Crucially, both ice caps are losing mass, again contrary to Booker’s assertion. The gain in Antarctic sea ice doesn’t appear to balance out the decline in Arctic sea ice, let alone the ice loss from the Greenland and Antarctic ice sheets.
Global sea level is rising
Satellite measurements show that the world’s average sea level has risen by around 3 millimetres per year since 1993, and this trend is continuing, as you can see in the graph below.
Image - AVISO sea level to 2012 (note)
Global average sea level calculated from satellite altimetry. Source: AVISO.
So measurements of global average sea level contradict Booker’s claim: “nor [are] sea levels rising”.
Variable outlook for hurricanes, droughts and heatwaves
Booker moves on to extreme weather, saying:
“nor [are] hurricanes, droughts and heatwaves intensifying as we were assured they would.”
Here Booker makes it sound like predictions of increases in droughts and intensifying hurricanes were more certain (‘assured’) than they actually were.
In fact, scientists have different levels of confidence about making predictions for different kinds of weather. For example, although the IPCC’s 2007 report says it is “very likely” (implying 90 to 100 per cent likelihood) that heat waves will continue to increase, scientists don’t yet understand other types of extreme weather so well, including tropical cyclones (hurricanes) and changes in drought patterns. Predictions of increases in droughts and hurricanes have therefore been correspondingly more cautious.
The IPCC’s recent review of the scientific literature (the SREX report) finds that hurricanes and droughts aren’t showing clear changes, so Booker does at least get that right. Heatwaves, however, have been getting longer in many regions, according to the SREX report.
Same time, same place, next Monday?