Thread by @Peters_Glen

"The result remains the gold standard for policy: global warming potential (GWP), which compares the impact of different greenhouse gases on climate." @KHayhoe @Wuebbles

🤔

That statement pulled me up...

1/

nature.com/articles/d4158…

I have no doubt about the statement before "When they argued that it was too difficult [to compare GHGs in a single metric], Houghton insisted that they must, because they were the best people in the world to do this."

2/

Don Wuebbles was instrumental in the Ozone Depletion Potential (ODP) & the GWP uses essentially the same concepts.

Houghton pushed as there was a need to compare GHGs for policy, though, I am not sure scientists were so keen on the GWP at the time, nor the years later.

3/

IPCC First Assessment Report “It must be stressed that there is no universally accepted methodology for combining all the relevant factors into a single [metric] ... A simple approach [ie the GWP] has been adopted here to illustrate the difficulties inherent in the concept.”

4/

"Indeed, has there been what might be termed an “inadvertent consensus”, so that the IPCC & policymakers have each perceived that the other was content with the concept & didn’t apply pressure to fully assess alternatives?"

link.springer.com/article/10.100…

5/

Have a read of the Editorial by Keith Shine, one of the fathers of the GWP, it is rather entertaining!
link.springer.com/article/10.100…

Not sure the GWP would be called the 'gold standard for policy'? @janfug @ReisingerAndy @oneill_bc

(Also read the section in IPCC AR5 WG1 Ch8)

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