Mike Hulme, BBC Green Room 16 Mar 09;
Last week's climate science conference in Copenhagen concluded with a declaration saying that the most serious warnings on climate change were coming true, and calling for immediate "action". But, argues Mike Hulme in the Green Room, it is not clear what action was being called for, nor precisely who was calling for it.
The Copenhagen conference brought between 2,000 and 2,500 researchers from around the world.
The three days saw 600 oral presentations (together with several hundred posters on display) on topics ranging from the ethics of energy sufficiency to the role of icons in communicating climate change to the dynamics of continental ice sheets.
I attended the conference, chaired a session, listened to several presentations, read a number of posters and talked with dozens of colleagues from around the world.
The breadth of research on climate change being presented was impressive, as was the vigour and thoughtfulness of the informal discussions during coffee breaks, evening receptions and side-meetings.
What intrigued me most, however, was the final conference statement issued on the closing day, a statement drafted by the conference's scientific writing team.
It contained six key messages and was handed to the Danish Prime Minister Anders Fogh Rasmussen.
A fuller version will be prepared and circulated to key negotiators and politicians ahead of the annual UN climate summit, to be held this year in December, also in Copenhagen.
Last week's conference has been widely reported as one at which the world's scientists delivered a "final warning" to negotiators about the necessity for a powerful political deal on climate.
Some commentators branded it "The Emergency Science Conference".
The six key messages include statements that:
* "the worst-case IPCC scenario trajectories (or even worse) are being realised"
* "there is no excuse for inaction"
* "the influence of vested interests that increase emissions" must be reduced
* "regardless of how dangerous climate change is defined", rapid, sustained and effective mitigation is required to avoid reaching it
There is a fair amount of "motherhood and apple pie" involved in the 600-word statement - who could disagree, for example, that climate risks are felt unevenly across the world, or that we need sustainable jobs?
But there are two aspects of the statement which are noteworthy and on which I would like to reflect: whose views does it represent, and what are the "actions" being called for?
Copenhagen consensus?
The Copenhagen conference was no Intergovernmental Panel on Climate Change (IPCC) event.
It was not a process initiated and conducted by the world's governments; there was no systematic synthesis, assessment and review of research findings as in the IPCC, and there was certainly no collective mechanism enabling the 2,000-plus researchers to consider drafts of the six key messages or to offer their own suggestions for what politicians may need to hear.
The conference was in fact convened by no established academic or professional body.
Unlike the American Geophysical Union (AGU), the World Meteorological Organization (WMO) or the UK's Royal Society - which also hold large conferences and from time to time issue carefully worded statements representing the views of professional bodies - this conference was organised by the International Alliance of Research Universities (IARU).
This little-heard-of coalition, launched in January 2006, consists of 10 of the world's self-proclaimed elite universities, including of course the University of Copenhagen.
IARU is not accountable to anyone and has no professional membership.
The statement therefore simply carries the weight of the secretariat of this ad-hoc conference, directed and steered by 10 self-elected universities.
The six key messages are not the collective voice of 2,000 researchers, nor are they the voice of established bodies such as the WMO. Neither do they arise from a collective endeavour of experts, for example through a considered process of screening, synthesising and reviewing.
Instead they were drafted largely before the conference started by the organising committee, sifting through research that they saw emerging around the world - some of it peer-reviewed, some of it not - and interpreting it for a political audience.
Taxing times
Which leads me to the second curiosity about this conference statement: what exactly is the "action" the conference statement is calling for? Are these messages expressing the findings of science or are they expressing political opinions?
I have no problem with scientists offering clear political messages as long as they are clearly recognised as such; and the conference chair herself, Professor Katherine Richardson, has described the messages as politically motivated. All well and good.
But then we need to be clear about what authority these political messages carry - that of the people who drafted them, and no more.
Which brings us back to the calls for action and the "inexcusability of inaction". What action, exactly?
During the conference there were debates amongst the experts about whether a carbon tax or carbon trading is the way to go. There were debates about whether or not we should abandon the "two degrees" target as unachievable, and whether there's a need to start researching and promoting a portfolio of geo-engineering strategies.
There were debates about the epistemological limits to model-based predictions of the future, and many other subjects besides - even the role of religion in curbing climate change.
These are all valid debates to have, and many of them mixed science, values, ethics and politics.
It therefore seems problematic to me when such lively, well-informed and yet largely unresolved debates get reduced to six key messages, messages that on the one hand carry the aura of urgency, precision and scientific authority - "there is no excuse for inaction" - and yet at the same time remain so imprecise as to dictate or resolve nothing in political terms.
In fact, we are politically no further forward after last week's conference. All options for attending to climate change - all political options - are, rightly, still on the table.
Is it to be a carbon tax or carbon trading? Do we stick with 'two degrees' or abandon it?
Do we promote geo-engineering or do we not? Do we coerce lifestyle change or not?
Do we invest in direct poverty alleviation in poorer countries, or in the New Green Deal in richer ones?
Mere urgency, especially precipitous urgency - the mantra of the new "Not Stupid" campaign launched in the UK last weekend - is not enough.
A gathering of international scientists and researchers has resolved nothing of the politics of climate change.
But then why should it? All that can be told - and certainly should be told - is that climate change brings new and changed risks, that these risks can have a range of significant implications under different conditions, that there is an array of political considerations to be taken into account when judging what needs to be done, and there is a portfolio of powerful, but somewhat untested, policy measures that could be tried.
The rest is all politics. And we should let politics decide, without being ambushed by a chimera of political prescriptiveness dressed up as (false) scientific unanimity.
Mike Hulme is a professor in the School of Environmental Sciences at the University of East Anglia (UEA), and was the founding director of the Tyndall Centre for Climate Change Research
The Green Room is a series of opinion article on environmental topics running weekly on the BBC News website
