MAN JUST DOESN'T MAKE THAT MUCH DIFFERENCE:

The latest report from the UN's Intergovernmental Panel on Climate Change (IPCC) is due out next week. If the leaked draft is reflected in the published report, it will constitute the formal moving on of the debate from the past, futile focus upon "mitigation" to a new debate about resilience and adaptation.

The new report will apparently tell us that the global GDP costs of an expected global average temperature increase of 2.5  degrees Celsius over the 21st century will be between 0.2 and 2 per cent. To place that in context, the well-known Stern Review of 2006 estimated the costs as 5-20 per cent of GDP. Stern estimates the costs of his recommended policies for mitigating climate change at 2 per cent of GDP - and his estimates are widely regarded as relatively optimistic (others estimate mitigation costs as high as 10 per cent of global GDP). 

Achieving material mitigation, at a cost of 2 per cent and more of global GDP, would require international co-ordination that we have known since the failure of the Copenhagen conference on climate change simply was not going to happen. Even if it did happen, and were conducted optimally, it would mitigate only a fraction of the total rise, and might create its own risks.

And to add to all this, now we are told that the cost might be as low as 0.2 per cent of GDP. At a 2.4 per cent annual GDP growth rate, the global economy increases 0.2 per cent every month.

So the mitigation deal has become this: Accept enormous inconvenience, placing authoritarian control into the hands of global agencies, at huge costs that in some cases exceed 17 times the benefits even on the Government's own evaluation criteria, with a global cost of 2 per cent of GDP at the low end and the risk that the cost will be vastly greater, and do all of this for an entire century, and then maybe - just maybe - we might save between one and ten months of global GDP growth.

Can anyone seriously claim, with a straight face, that that should be regarded as an attractive deal or that the public is suffering from a psychological disorder if it resists mitigation policies?

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