For me, what was interesting about the testimonies given in public to the NAS panel was the non-committal attitude to whether there was sufficient robustness to the usage of proxies in creating reconstructions of past temperatures. The fact that, with one notable exception, nobody was prepared to say that they could predict past temperatures to within an error of 0.5C, nor did they express any confidence in reconstructions projecting back beyond the 15th Century.

So what? Well, given this uncertainly about “Hockey Stick” reconstructions – it does pose a couple of relevant questions for me.

First, why did the TAR SPM rely on the MBH98 graph so heavily in terms of selling the message to policymakers given the health warnings expressed in the testimonies to the NAS Panel? For me, this has relevance to the forthcoming 4AR in 2007. The IPCC process is meant to summarise the current state of understanding as regards the climate. If the mechanisms of the IPCC don’t provide sufficient checks and balances when a new argument is presented (as was in the case of MBH98 – particularly in respect of its claim to be a new statistical analysis), you have to question whether the IPCC process is motivated to not ask akward questions of the contributors.

Second, the usage of the hockey stick claim that this is the warmest period in a thousand years is used in the media by some serious scientists. For example, Phil Jones was happy to assert this claim in a recent interview on the BBC “Today” programme (a national radio breakfast programme which does influence the political agenda of the country). Again, given the uncertainies expressed in the NAS testimonies – isn’t this a case where a scientific study has developed political status? Phil Jones, did not offer any qualifications to his claim, rather it was presented as a bold fact to the listening audience.

In terms of a political debate – I believe that this report has meaning. In terms of a scientific debate on climate change – it has little relevance.

Thanks.

This post is simply a reference to previous discussions. My views are that it doesn’t matter for some things and it does for some others. Please do read what I wrote.

You were the one quoted as saying that it doesn’t matter outside science!

Thanks!

You seem to be stuck in an all-or-nothing keystone vs it-doesn’t-matter. Both are wrong. It isn’t a keystone. It does matter.

What has IPCC to do with the receoption of W+S?

It will be intersting to see the report come out.

I do however think if there actually had been significant problems it would have been politically important.

The MWP and LIA help establish the bounds of natural climate variability during the Holocene -the current warm period may not yet have exceeded the warmth of the approx 400 year MWP, in which case where was the climate catastrophe that is predicted for the modern warm period?