September 04, 2007

Global Warming Again

The Daily Tech website has a lead story today, Less than half of scientists support Global Warming. A rather interesting story you might think and you'd be right- afterall if less than half of the world's published scientists did support global warming- we non-scientists might have to change our opinions of what was going on. Once you go further down you realise that we are dealing with a research paper, which used the same search terms as a previous research exercise which found large support for global warming up till 2003, and which was written by an accredited academic, but it doesn't appear to be published yet. Fair enough- there are still things we can work out from the Daily Tech story as the website helpfully supplies a summary of his results:

Of 528 total papers on climate change, only 38 (7%) gave an explicit endorsement of the consensus. If one considers "implicit" endorsement (accepting the consensus without explicit statement), the figure rises to 45%. However, while only 32 papers (6%) reject the consensus outright, the largest category (48%) are neutral papers, refusing to either accept or reject the hypothesis. This is no "consensus."


The website sums up the research by stating affirmatively that this means that there is 'no consensus' on global warming.

Well lets be careful about this. That's not exactly what the results say. Its worth at this point remembering what happens when you write an academic paper- as someone who has written a good fair few in his time, and given seminars in various places, the standerd practice is to try and be concise. That means that you avoid mentioning what you don't have to mention in order to support your argument- even though I agree with the statement that the English Civil War was not a straightforward class revolution, I don't need to really say it because my paper concerning the political theory of Henry Ireton doesn't really deal with the question. Similarly these neutral papers are papers which got published without taking a view on global warming- ie their arguments made sense no matter what way the question was decided- ie and this is the crucial step their authors for the sake of concision didn't need to mention global warming.

The neutral papers in this case are a red herring. Instead of taking them into the calculation lets take all those papers which according to this research expressed a view about global warming- that's 38 which took a view for, 237 or 238 which took a view vaguely assuming global warming (sorry the numbers aren't clear because 45% of 528 is 237.6 it could be either lets presume for the sake of argument 237, it won't make much difference in the end) and 32 which argued against. Out of this new sample of 307 papers which took a view on global warming- only 32 that is roughly 10% took a view against the idea of manmade global warming, and roughly 12% took a view for it whereas 77% of the scientists who took a view implied or assumed it existed. If we discard therefore those whose research didn't involve global warming, we find according to this boasted report that 89% of scientists who made a reference to global warming supported the theory in some way.

Now its worth going further just to explain those numbers even more- and as a PhD student I can use my own experience of how academia works in my area to substantiate that. When something achieves consensus very few academics write about it at all. In the 1960s the way to write about the English Civil War was as a Marxist, in the 1970s great historians including my supervisor discarded the Marxist interpretation of the war and nowadays noone writes about it because its not an issue- people research other things. Indeed its quite possible that the majority of articles about the Marxist theory of the English Civil War published last year supported it! That's not because it was right- but because quite simply most historians have moved on to study other aspects of the English Revolution. Similar things happen in science- I think its very interesting that the largest group of papers in this sample are the group which assumes global warming- that would suggest to me a scientific consensus- indeed exactly what one might expect from the IPCC report. At the moment just as scientists assume Einstein is right and work on the basis of special or general relativity, so they assume global warming is right. There are a small group of people still working to reinforce the theory- and as in all scientific areas rightly a small group working to overthrow the consensus- but most scientists seem from this research to be assuming the theory works, and working on other things.

That is apart from the other group which furnishes the material for the headlines, who feel no need to include any discussion of climate change in their work. Now that could suggest that climate change is dying as an explanation for other things- but given the paper is yet to be published and therefore we can't see the methodology behind it, its difficult to say. What we can say for the moment, is that of the group of scientists who mentioned global warming between 2003 and 2007, most of them assumed it, a few on either side challenged it and that is exactly what we would expect from a consensus interpretation.

LATER
Others have pondered on this- particularly Tim Lambert who examines some of the contenders for being against climate change- again the picture is unclear- and the difficulty appears to be in the definition of what exactly against means. It is also worth noting that the author of the original survey which suggested a scientific consensus, Naomi Oreskes responds here citing many misrepresentations of her work in what has been published so far of this new research and she also has republished a book chapter in which she discusses her earlier conclusions but in 2007 here.

8 comments:

Vino S said...

Interesting article, Henry, and it is good to shed some light on the way academic papers are drafted (since i haven't had experience of writing them).

It does strike me that, from what you say and from what others say, global warming is the most credible explanation of the situation. It may not be 100% proven (nothing can be - scientific theories are only scientific if they can be falsifiable, as Popper says) but we have to work on the assumption that the existing studies are most probably correct.

It strikes me, as a layman, as prudent to then take measures to alleviate this - just as you would buy insurance to alleviate a risk (even though the risk might not happen and might not cause as bad consequences as people fear).

Michelle Hudson said...

I have a blog containing good information on global warming. Ozone has doubled since the mid-19th century due to chemical emissions from vehicles, industrial processes and the burning of forests, the British climate researchers wrote. Carbon dioxide has also risen over that period. History of global warming is very deep since 1850.

Lord Nazh© said...

Vino: even the 'bad' papers he cites will believe in global warming (or climate change) it is the 'man-made' part that is the focus.

Gracchi: While this study may not be the best, it was the exact same study that produced the headlines of the 'consensus' before '03

Gracchi said...

Well Lord N as it hasn't yet been published we don't know that- and the author of that first study seems to doubt it.

The simularity is the search term used to identify the papers- at least that is what Daily Tech says- I don't see how that would invalidate my argument.

Mike M. said...

Lubos Motl fisked Naomi Oreskes original paer back in 2005...
http://motls.blogspot.com/2005/05/oreskes-study-errata.html

Gracchi said...

He did. But again its worth probing what he found. He found that there were more papers which worked on paleo-climate change or methodologies than she found- again that's not inconsistant with the view of consensus. He found 34 papers which denied global warming whereas she hadn't found one.

Ok lets look in a bit more detail at that last number because it exposes something. Actually he says in an update to the post that many of those 34 have to be withdrawn- because Professor Pieser has found errors in that data. What he is doing is relying upon another person's data (fair enough) but claiming it as his own.

Ok Dr Peiser, he doesn't have a Professorship, is a social anthropologist from Liverpool John Moores University who did critique Oreskes's paper. But subsequently Dr Peiser has admitted to serious errors in his own work- and withdrawn many of his conclusions- see here, the original abstracts which he said were abstracts from deniers are here- I personally can spot many that I consider back global warming- see for instance abstract 5 and abstract 6 both of which assume that global climate change is happening. Given that Motl intepreted the data in exactly the same way as Peiser, I think he relies on Peiser's withdrawn argument- and his fisking therefore is wrong.

But that doesn't ultimately effect the real question of this- which is about this current research.

Gracchi said...

Sorry last sentence should have said this article which is about this current research!

Effects of Global Warming Activist said...

there cant be enough info on global warming! good to see some more research going into it! http://www.effectofglobalwarming.com