Krugman, this time vs Feldstein on carbon emissions

Paul Krugman keeps free-riding on his reputation to make inaccurate statements without checking the facts. Worse still, he does it against reputable scholars - first Niall Ferguson, now Martin Feldstein.

In the latest entry in his blog Krugman objects to Feldstein's statement that "a 15 percent fall in US CO2 output would lower global CO2 output by less than 4 percent". He retorts "the right comparison is not with current emissions levels but with what they would be in the absence of the policy - a much bigger number".

I am not sure his logic here is right. But in any case, in ten years' time US emissions will be exactly the same as in 2008 if they are to follow the same pattern this recession as they did during and after the much milder 1980. And ten years is precisely the timeframe Krugman and Feldstein are both talking about. So, to put it bluntly, Krugman is wrong when he states that in ten years' time US emissions will be a much bigger number than now.

As before, this is based on my own calculations of emissions from BP's 2008 Statistical Review of World Energy.