This post is by Myles Allen of the University of Oxford:
As a vocal supporter of the traditional system of scientists communicating through peer-reviewed channels ( Nat. Geosci. 1, 209; 2008 and associated debate at Peer-to-Peer), I was hesitant about writing a critical Commentary on the Feature ‘A safe operating space for humanity’ by Johan Rockström et al in the 24 September issue of Nature (Nature 461, 472-475; 2009) in a non-peer-reviewed forum. The Nature and Nature Reports Climate Change editors had clearly thought through this argument: the Feature was not itself peer-reviewed, so no golden rules would be broken in publishing a series of commentaries alongside it in Nature Reports Climate Change.
The problem is that packing the point into a few hundred words, and slipping into the usual bloggers’ trap of feeling you have to shout loudly on the internet or no-one will listen, means that the end result reads very black-and-white. Corresponding with Johan Rockström over the past week, it emerges we agree on far more than the tone of my Commentary, ‘Tangible targets are critical’ (Nat. Rep. Climate Change doi:10.1038/climate.2009.95), probably implies. I understand that Rockström et al. had not originally intended to make the link between a six-degree climate sensitivity, the two degrees target and 350 p.p.m. a focal point (as I read it) of their Feature. Likewise, they observe, reasonably enough, that limiting cumulative carbon dioxide emissions to one trillion tonnes of carbon is just another way of framing the climate boundary, with (as I acknowledge) remarkably similar implications to 350 p.p.m.
If this had been done the old-fashioned way, Rockström et al. would almost certainly have had to qualify their reliance on a six-degree climate sensitivity in the course of the usual to-and-fro with referees. And I in turn would have toned down a lot of my objections. The end result would undoubtedly have been blander on both sides, but would that really have been much of a loss? Following what was, for me, an experiment, I still feel it is very much an open question whether scientific communication in general benefits from direct publication rather than allowing rough edges to be smoothed off through traditional peer-review.
Myles Allen is at the University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
Johan Rockström and his co-authors argue in a Nature Feature that to avoid catastrophic environmental change, humanity must stay within defined ‘planetary boundaries’ for a range of essential Earth-system processes. If one boundary is transgressed, then safe levels for other processes could also be under serious risk, they caution. Seven expert commentaries respond to this proposal in Nature Reports Climate Change, one of which is by Myles Allen. All these articles can be accessed from this index page.
There is an associated Nature podcast in which Johan Rockström is interviewed and editor Ehsan Masood provides further analysis.
A longer paper upon which the Nature Feature is based, ‘Tipping towards the unknown’, is available at the Stockholm Resilience Centre.
Nature news special: The road to Copenhagen.