Scientist warns against overselling climate change

Climate change forecasters should admit that they cannot predict how global warming will affect individual countries, a leading physicist has said.

Louise Gray, The Telegraph 3 Dec 08;

Lenny Smith, professor of statistics at the London School of Economics, said that scientists risk "blatantly overselling what we know. That could bring everything down and cost the world valuable time".

As the world gathers to decide a new way forward on climate change, he said the data produced by models used to project weather changes risks being over-interpreted by governments, organisations and individuals keen to make plans for a changing climate – with dangerous results.

"They are certainly right on the basic story of global warming. Man-made climate change is real.

"However, there is a risk that something important will happen that is not predicted by any of today's models – and they cannot give us trustworthy forecasts of climate for regions as small as most countries are. The bottom line is that the models help us understand pieces of the climate system, but that does not mean we can predict the details."

More than 192 countries have gathered at the UN Climate Change Conference in Poznan, Poland to decide a new Kyoto Protocol. The main issues will be whether developed countries like the US will commit to cutting emissions, paying developing countries to stop deforestation and an adaptation fund to help poorer people adapt to climate change.

Professor Smith, told the New Scientist magazine, said climate change negotiations should stick to the facts.

"Effective application of climate science hinges on clear communication of which results we believe are robust and which are not.

"Any discussion of such limits can be abused by those seeking only to confuse. But failing to discuss those limits can hinder society's ability to respond, and also compromise the future credibility of science.

"Let's forget the spurious certainties, and even the spurious possibilities and concentrate on what matters."