It is time to stop quivering in our boots in pointless fear of the future and just roll up our sleeves and build it.
- Ray Pierrehumbert

Friday, April 6, 2007

What about the other 11%?

Commentary on the WGII SPM on Slashdot spans the usual gamut from snarky through self-importantly clueless to insightful, and as usual for nontechnical articles the comment moderation system is not especially helpful. My impression that the balance of Slashdot opinion was moving in the wrong direction is not confirmed this time; it seems to be about 25% informed and 75% ill-informed, with the ill-informed split evenly between worried, unworried, and more or less misguided difference splitting (a.k.a. Broderism).

One presumably skeptical question seemed genuine and insightful enough, though. What does "consistent" mean? It's stated that 89% of the observational records showing significant change are "consistent" with warming. Does this imply that 11% are "inconsistent"? What does this mean for the "consistency" of the record as a whole?

I think we'll be hearing this question again.

I didn't see any answer in the SPM. Did I miss it?

2 comments:

Dano said...

80:20 rule strikes again.

Best,

D

inel said...

Consistency, consensus, probability, uncertainty … all these words tie in with contrarians' desire to prevent action to combat climate change by sowing doubt amongst non-scientists. This is easily done by making unwitting members of the public believe that science deals with facts and facts must be 100% correct before we act, and in this case scientists cannot provide 100% proof that climate change is happening nor 100% proof that any changes are due to human activity therefore we should not act.

The word "consistent" comes up many times in both SPMs this year. Ho-hum. Here we go again … :-(

Indications that are inconsistent with warming do not mean warming is not happening, just as indications that are consistent with warming do not prove that warming is happening. These are just inputs in the form of evidence to be assessed.

The record is completely consistent within itself in that it lays these points out clearly, without covering up the points of inconsistency (!), so that policymakers are able to make their own informed judgements.