Thursday, June 16, 2011

Lindzen and Choi 2011: lots of improvements

I was preparing a short climate talk and I decided it was sensible to at least mildly study the newest paper by Richard Lindzen and Yong-Sang Choi that will appear in Asia-Pacific Journal of Atmospheric Sciences:
On the observational determination of climate sensitivity and its implications (full text PDF)
I think it's a much more refreshing reading than the biased reactions at PNAS where the paper was previously submitted.

The authors have admitted several errors of their 2009 paper that were pointed out by subsequent papers and they believe that they have addressed them and the mistakes are fixed in the new 2011 paper.

The measured response of the energy fluxes at the top of the atmosphere to the changes of the sea surface temperature is still significantly larger than claimed by the IPCC and the climate sensitivity ends up being 0.7 °C. In fact, their 99-percent confidence interval is 0.5 - 1.3 °C. Imagine: they are 99 percent certain that the climate sensitivity can't exceed 1.3 °C. This is, of course, qualitatively incompatible with the IPCC whose lower bound is 2 °C.

Quite generally, I like the fact that their method uses lots of data point - a more detailed measurement of the responses to the atmospheres to many episodes of warming and cooling of the seas. This is the real source of their pretty impressive accuracy.

If the calculated sensitivity 0.7 °C were pretty much right, it would follow that one expects no warming by 2090 or so - when the CO2 will be twice the pre-industrial value - because a warming by 0.7 °C has already occurred so there's "nothing left", assuming for the sake of simplicity that all non-CO2 sources of warming average out over two centuries or so.

Feedback about the paper will be appreciated. It would be great if some TRF readers actually read the whole paper.

Nude Socialist and drought

Shockingly enough, Nude Socialist that previously promoted climate alarm of all sorts wrote that the droughts are not due to "global climate change" and the recent frequency of droughts is "not that unusual", anyway.

The Independent, Mark Lynas sensible quote Steve McIntyre

The Independent which was traditionally the most annoyingly politically correct major British newspapers has tried to promote a new IPCC scandal. They wrote preposterous statements about the ability of the ludicrous sources of energy could provide the globe with 77% of our energy needs by 2050.

They actually hired a Greenpeace activist to write this portion of the IPCC report. The Independent and activist Mark Lynas agree with Steve McIntyre that this behavior wasn't appropriate for a nominally scientific organization and the statements are absurd, too.


  1. The "climate sensitivity" is a constant in a relation between an observable CO2 concentration and an unobservable equilibrium temperature. That the latter is unobservable has the consequence that this relation is not refutable, thus lying outside science.

  2. Terry, climate sensitivity (CS) is the amount that global average temperature will change with any input, not just CO2.

    Equilibrium temperatures can be derived from palaeontological observation.

    CS is very much at the heart of the scientific debate. The overwhelming majority of the science points to a mean value of 3*C.

    Spencer and Lindzen struggle to make simple climate models point to a lower CS value.