A reader some time ago sent me a copy of a journal article that dealt with the question in the title. I read it and thought about it, and today I have some space to write about it. The author of the piece is a guy called Daniel Sarewitz, who is now the Director of the Centre for Science, Policy and Outcomes of the University of Arizona. He runs the Centre’s Washington office (yes, I know that Arizona is quite a way from Washington DC). He writes a lot for Nature, and what I have read of his work impresses me with its clarity and sense.
The essay in question is entitled ‘How science makes environment controversies worse’, and it appeared in Environmental Science and Policy in 2004. Its argument is straightforward, and I’ll set it out in three parts.
First, in any kind of environmental controversy — climate change is one, but so is genetically modified foods, and what to do with nuclear waste — ‘science supplies contesting parties with their own bodies of relevant, legitimated facts about nature…’ Each side chooses its own data and theories, according to the particular world-vision and interests that it has. There are plenty of theories, and plenty of data.
You can see this admirably portrayed in the global warming issue. The orthodox cling to the data and theories set out in the IPCC’s several reports, while the dissenters point out the weaknesses and incompleteness of the reports, and bring forward other theories and other data. As has been said many times, each side talks past the other.
Second, in any environmental controversy those involved bring with them different and competing disciplinary approaches, which may be related to, or are in harmony with, ‘competing value-based political or ethical positions’.
Readers in Canberra will be familiar with the annual problem of culling the resident kangaroo population which, because of the absence of natural predators and the amount of fencing, means that hundreds of kangaroos are shot each year. From the perspective of a systems ecologist, the culling is necessary so that kangaroos do not deprive other features and life forms of their own patch. That is not an acceptable position for those who see the kangaroos as animals who need their own living space.
Third, when people talk about ‘uncertainty’, what is involved is not necessarily ‘a lack of scientific understanding but […] the lack of coherence among competing scientific understandings, amplified by the various political, cultural, and institutional contexts within which science is carried out.’
You can see this at every level in the ‘climate change’ debate. While most participants accept that adding carbon dioxide to the atmosphere must in some measure increase temperature, nothing follows from this proposition. Extra warming may be beneficial to the environment, or beneficial here but not there. Or the addition may occur quickly or slowly. Water vapour and clouds may intensify the process, or a minimise it. Different people from different disciplines are involved here.
It may be that more CO2 will enhance plant life to the point where it takes as much out of the atmosphere as it can get, thereby reducing the speed of the carbon dioxide accumulation. The more we learn, the more there is to know, and the more room, paradoxically, for disagreement, because of Sarewitz’s First and Second reasons. I remember how often a successful research project funded by the public purse always finished with an appeal for extra funds to find out more: we can never learn enough about anything.
Where does all this get us? For Sarewitz the conclusion is clear: politics plays the important role, and until the politics is sorted out science cannot really get a look-in, as we say in Australia. I think he’s right, at least for Australia, and probably for everywhere. As he says himself, ‘the scientific debate itself conceals those preferences behind technical arguments. This camouflaging process reflects, in part at least, the enduring social commitment to the idea of scientific facts as detached from values, and the consequent desire of everyone on all sides of a given controversy to legitimate their value preferences with an allegedly independent body of facts’.
I know that I do it myself. For reasons which I cannot wholly explain even to myself, something about the AGW scare aroused a strong scepticism in me several years ago. While I kept reading to see why reputable scientists took the other view, I could all too easy see the flaws in their position. That situation remains true today.
What are the flaws in my position? I probably do not take the Precautionary Principle seriously in the case of global warming, though like everyone else I follow its logic in many other fields of life, like insurance for my house. I discount the possibility of catastrophe. I give the climate models little credence, though I recognise that models underpin much of the technological underpinning of life in developed countries. I see little likelihood the seas acidifying, or of rising much above their present levels in the rest of the century. I may be wrong about all of this, but the evidence that I see suggests that I am more likely to be right.
Like Sarewitz, I think that Australians will finally come to terms with ‘climate change’ one way or another. My guess is that it will lose its force, and be replaced by some other scare. But I could be wrong, and warming reappear. Whatever the case, science will not be the determinant. Politics will have that role.
Don,
Thank you for this thought provoking post.
I’d make two points.
I don’t agree with this statement. ‘Climate Sensitivity’ and the ‘Damage
Function’ are two of the most important inputs to analyses of the costs and
benefits of climate change and to the cost benefit analyses of mitigation
policies. Both these inputs are highly
uncertain. The uncertainty of climate sensitivity
has hardly changed in 25 years. The
uncertainty is a measure of how little we know about it. The real value of climate sensitivity would
have a small range at any given global average temperature if we could determine
it to a precision of say +/-0.1 C (it would be different in an ice age and
different when warmer than now, varies according to the extent of ice sheets on
the planet and other variables, but at any time is would have a small uncertainty
range). Our uncertainty of climate sensitivity is so
large as high as to be effectively meaningless.
Our knowledge of the damage function is worse than for climate
sensitivity. As world expert climate
cost benefit analyses and carbon tax, Professor Nordhaus, says:
p24, http://nordhaus.econ.yale.edu/Accom_Notes_100507.pdf
World expert on estimating the damage function, Richard Tol
says:
p96, https://sites.google.com/site/climateconomics/
The title of your article asks:
I agree with your point, Peter, but it’s not inconsistent with what Sarewitz wrote. As you know there are various, different estimates of climate sensitivity. It’s not that only one of them will be right — none of them may be right. But all the creators argue from their own positions…
[…] What do I like about the book? Well, it has a light-hearted side to it, which is a tonic, given that so much writing on these topics is deadly serious and deadly dull. Spooner’s illustrations are great fun. The graphs are excellent, and in this field you absolutely need to compress a lot of data into graphs. I’ve seen a lot of the graphed material before in various forms — indeed I’ve seen a lot of the argument before too, but the argument is sensibly and systematically organised. What it does is to present the orthodox position, and show what is wrong with it, and in doing so it illustrates rather well what I wrote yesterday. […]