A changing climate for the IPCC

It is not so much that an error was made, whether this is attributed to the original maverick scientist who made it, to the lapse in the IPCC's peer-review process, or even to Pachauri's rather arrogant defiance.

No, the error's significance lies in the fact that it proves definitively that not everything written by the IPCC - or declared by its senior spokespersons - is true. So sceptics and bloggers are now scrutinising other chapters in the IPCC report as never before to find further evidence of inaccurate or poorly warranted statements and claims.

And some have been found - for example, attributing the rise in disaster costs to climate change and claims that up to 40 per cent of the Amazon rainforest could react drastically to drought.

Time for change

What does all this mean? Well, it doesn't mean that the well-authenticated, headline conclusions about human impacts on the climate system are undermined. Nor does it mean that concerns about the risks of future climate change are misplaced.

But it does mean that the IPCC in its next assessment must be more scrupulous in adhering to its basic ground rules.

It also probably means that the rules must be revised, especially regarding the use of non-peer-reviewed sources and the ways that reviewers' comments are handled.

The danger of claiming, or being offered, ultimate authority - whether for determining how people should live or how policies should be made - is that it can leave you vulnerable to human error and poor practice.

By setting itself up as the impeccable and authoritative source of ultimate scientific knowledge about climate change, and with advocates justifying their case for action with "as the [IPCC's] science demands", the IPCC's fall was almost inevitable.

A little less hubris from the IPCC might have made Pachauri more careful about using phrases such as “voodoo science”. And a little less deference to science that “demands action”, and a more honest articulation of the ethical and political reasons for their proposed actions, would have left climate change campaigners in a stronger position.