When the topic turned to climate change on Q&A, Malcolm Turnbull shone! If only Kevin Rudd could be as clear!
John Roskam, on the other hand, is a drip. Take his confident assertion about Philip Jones saying “there has been no global warming since 1995”. Indeed, this was reported in the press, for example in The Vancouver Sun: Figuring out how ‘global warming’ becomes ‘no global warming’.
Whatever your thoughts about global warming, you have to feel a little sorry for Phil Jones.
First, the formerly private e-mails of the former director of the Climate Research Unit at the University of East Anglia in England were hacked, leading to the so-called climategate scandal. And now, media everywhere are putting words in Jones’s mouth, words that are the exact opposite of those he actually spoke.
In an interview with the BBC last week, Jones said he is "100-per-cent confident the climate has warmed," and "there’s evidence that most of the warming since the 1950s is due to human activity."
One day later, the United Kingdom’s Daily Mail newspaper’s headline read: "Climategate U-turn as scientist at centre of row admits: There has been no global warming since 1995." …
However, The Vancouver Sun goes on:
Jones clearly recognizes this, as he told the BBC: "Achieving statistical significance in scientific terms is much more likely for longer periods and much less likely for shorter periods."
In other words, whether a change in temperature is statistically significant depends on more than the real change temperature — sample size, or the period of time, is crucial.
That’s not all. Statistical significance tells us nothing at all about whether a difference, in temperature or anything else, is practically significant. We see this frequently in medicine, where the small benefit produced by a given medical intervention might not be statistically significant, but might make an enormous difference in patients’ lives.
Similarly, a statistically insignificant change in temperature might have profound effects on the environment. Moreover, a minuscule change that has no practical effect might nonetheless be significant, particularly if scientists are considering a long time period.
For a thorough rubbishing of John Roskam’s only too typical cherry picking to suit his ideological tastes, or rather of what the snippet that stuck in his brain was really about, go to Daily Mangle on Real Climate.
Yesterday, the Daily Mail of the UK published a predictably inaccurate article entitled “Climategate U-turn as scientist at centre of row admits: There has been no global warming since 1995″.
The title itself is a distortion of what Jones actually said in an interview with the BBC. What Jones actually said is that, while the globe has nominally warmed since 1995, it is difficult to establish the statistical significance of that warming given the short nature of the time interval (1995-present) involved. The warming trend consequently doesn’t quite achieve statistical significance. But it is extremely difficult to establish a statistically significant trend over a time interval as short as 15 years–a point we have made countless times at RealClimate. It is also worth noting that the CRU record indicates slightly less warming than other global temperature estimates such as the GISS record.
The article also incorrectly equates instrumental surface temperature data that Jones and CRU have assembled to estimate the modern surface temperature trends with paleoclimate data used to estimate temperatures in past centuries, falsely asserting that the former “has been used to produce the ‘hockey stick graph’”.
Finally, the article intentionally distorts comments that Jones made about the so-called “Medieval Warm Period”. Jones stated in his BBC interview that “There is much debate over whether the Medieval Warm Period was global in extent or not. The MWP is most clearly expressed in parts of North America, the North Atlantic and Europe and parts of Asia” and that “For it to be global in extent, the MWP would need to be seen clearly in more records from the tropical regions and the Southern hemisphere. There are very few palaeoclimatic records for these latter two regions.”
These are statements with which we entirely agree, and they are moreover fully consistent with the conclusions of the most recent IPCC report, and the numerous peer-reviewed publications on this issue since. Those conclusions are that recent Northern Hemisphere warming is likely unprecedented in at least a millennium (at least 1300 years, in fact), and that evidence in the Southern Hemisphere is currently too sparse for confident conclusions. Mann et al in fact drew those same conclusions in their most recent work on this problem (PNAS, 2008).
Unfortunately, these kinds of distortions are all too common in the press nowadays and so we must all be prepared to respond to those journalists and editors who confuse the public with such inaccuracies.
Update 2/16/10. Phil Jones has confirmed to us that our interpretations of his comments in the BBC interview are indeed the correct ones, and that he agrees with the statements in our piece above. He and his CRU colleagues have also put up an response to some of the false allegations in a previous piece in the UK Guardian. We’ll report further such developments as they happen.
Read that, Roskam, and don’t try that particular one on again.
Trouble is that those who think Roskam and his think-tank are fonts of wisdom will have believed his distorted version of what Phil Jones said. That’s the level at which so much climate denial propaganda – and that is absolutely what it is – works. Disgust with that is what has led to my taking the stand I have lately, on the new page for example. Everything on that page is from reputable and reliable sources.
With a handful of honourable exceptions, most of the climate change deniers are frauds or fools. Roskam is probably the second – on this anyway.
Which takes me back to Malcolm Turnbull. Admirable and sane.
- Comment on Twitter: Very much hoping John Roskam gets a seat at next election. You can never have enough nutbags.
By the way, I think Peter Garrett probably will resign. I think he should for the sake of the government. (See my previous post.)