Graham Readfearn writing in The Guardian, on Abbott Government chief business adviser Maurice Newman’s claim that the world should prepare for global cooling which was published in The Australian on 14 August 2014:
Growing evidence?
At the beginning of the column, Newman claims a recent article in the journal Astronomy & Astrophysics “adds to growing evidence that climate change is determined by the sun, not humans”.
The problem with this statement is that the journal article in question did not even consider the interactions between the sun and long-term climate change.
Even one of the climate sceptic websites that recently featured this research, said: “Unfortunately, it was beyond the scope of this paper to address the potential impact of solar activity on climate.”
Professor Steve Sherwood, director of the Climate Change Research Centre at the University of New South Wales, explains:
Evidence that the sun influences climate has decreased, not increased. About a decade ago calculations showed the sun caused about 10 per cent of the warming observed since the late 1800s, but it is now estimated to be only about 5 per cent. This new paper does not change these estimates at all, it is only an attempt to extend the sunspot record back to times before direct observations began a few hundred years ago. The paper makes no mention of climate, because it does not have any new implications for climate.
Since 1980, during which time we have seen strong warming, solar output has if anything declined slightly. In fact, it is looking increasingly doubtful that the sun even had much to do with the so-called “little ice age”, which most mainstream scientists used to attribute to the minimum in sunspot activity at roughly the same time, but now looks to have been caused mainly by volcanic eruptions.
Newman tells his readers that experiments at the Large Hadron Collider (LHC) in Europe had “validated” a hypothesis from Danish physicist Professor Henrik Svensmark that “the sun alters the climate” by interacting with cosmic rays.
The former ASX chairman makes it sound like a done deal. But what did the lead author of that research actually think? Did it “confirm the hypothesis” that the sun alters the climate “by influencing cosmic ray influx and cloud formation” as Newman had claimed?
So that’s a no, then (minor nit, as Nature also explained, the experiment didn’t use the LHC, as Newman had claimed, but rather the same bit of kit – a particle accelerator - that feeds the LHC).
Newman and the IPCC
Newman wrote that the United Nations Intergovernmental Panel on Climate Change “and its acolytes” tend to “pay scant attention” to science that might “relegate human causes” as the driver of climate change.
Professor Sherwood was a Lead Author on the latest IPCC report chapter to look at these cosmic ray claims. He told me:
In writing the relevant section of the report, we examined Svensmark’s work along with many other relevant studies. It is quite clear that the evidence suggesting that cosmic rays influence cloud cover, does not hold up to scrutiny. The IPCC is quite comprehensive in assessing the scientific literature and making an overall assessment. If there is any cherry-picking going on, it is by the so-called skeptics, who typically focus on a tiny handful of papers and often draw unwarranted inferences from them not made by the authors themselves, as Newman has done in this case.
Sly misrepresentation
Newman name checks other organisations and scientists to try and bolster his argument.
He quotes work by “leading British climate scientist Mike Lockwood, of Reading University” to try and convince readers that the sun might be the dominant driver of the climate.
But Newman doesn’t mention what Lockwood actually thinks about these claims of cosmic rays or the sun dictating global temperatures
After his work was misrepresented in the British press last year, Lockwood responded on the website Carbon Brief:
So what do we think the effect of a return to Maunder minimum conditions on global mean temperatures would be? The answer is very little.
In a paper with scientists from the Met Office’s Hadley Centre, we used an energy balance model to show the slowing in anthropogenic global warming associated with decline in solar irradiance to Maunder minimum levels.
We found the likely reduction in warming by 2100 would be between 0.06 and 0.1 degrees Celsius, a very small fraction of the warming we’re due to experience as a result of human activity.
I sent Newman’s article to Lockwood to ask if he felt his work and his views were being fairly represented. Suffice to say he’s not too happy. He wrote:
The wording in the quote you sent me is a very sly misrepresentation. As a scientist I try to write sentences that are unambiguous ... but this is deliberately ambiguous to make it look like I am saying something that I certainly am not. I have never, ever written anything whatsoever about the “year without summer”, so I have never ever connected it to solar variability and the Dalton minimum. So if I trim the sentence down to “... Mike Lockwood, of Reading University, found 24 occasions in the past 10,000 years when the sun was declining as it is now, but could find none where the decline was as fast. He says a return of the Dalton Minimum (1790-1830) is ‘more likely than not’” Then I would be happy - but the addition of the phrase which included “the year without summer” makes it look like I am connecting that year to the Dalton minimum which I certainly am not. There is absolutely no credible evidence whatsoever that the “year without summer” was either caused by low solar activity or was in any way significant as an indicator of global climate trend.
I also asked Lockwood what he thought of Newman’s claim that there was “growing evidence that climate change is determined by the sun, not humans”. Lockwood said:
[This claim] is, frankly, scientifically ludicrous. There are a few papers that use inadequate statistical techniques to claim a link between global temperatures and solar activity. Proper significance testing against an appropriate noise model invariably shows that the probability that these sun-global climate connections are purely coincidental is extremely high and that they have been selected whilst a very large number of counter examples have been ignored. This is bad science: it’s equivalent to finding on albino rabbit and declaring all rabbits are albino.
There have been many studies, including ones that I have been involved in, that show the solar influence on global mean surface temperatures is extremely small. I personally think there is evidence for some interesting effects in winter (and only in winter, and there are compelling scientific reasons why only in winter) in locations that are strongly influenced by the northern hemisphere jet stream.
However these effects are re-distributions of temperature and so, for example, if Europe suffers a cold winter, Greenland has a warmer one. Hence these are regional and season climate changes and quite distinct from global climate changes.
That looks like one less Christmas card for Maurice Newman.
But there’s still more to go at here. Newman quotes a University of Pennsylvania professor of psychology Philip Tetlock as saying: “When journal reviewers, editors and funding agencies feel the same way about a course, they are less likely to detect and correct potential logical or methodological bias.”
The quote is actually a decade old and comes from an article published in the journal Political Psychology.
Newman probably got it trawling the blogs of climate sceptics (an article discussing the paper was reposted on the UK’s Global Warming Policy Foundation website earlier this month), which is where, in my view, he probably gets most of his ideas about climate science.
You might think, given the context of the article, that Tetlock was talking about environmental science or climate change.
But no. The Tetlock article was discussing his concerns about the preservation of the discipline of “political psychology”. Most of the article is discussing issues around war and peace and racism.
