PowerSwitch

Here's a new essay by Hansen et al:

http://www.columbia.edu/~jeh1/mailings/ ... re2009.pdf

(the 1951‐1980 base period)

Devil's adv here, but wasn't that spell cooler-than-average because of smoke and the like? Or was that an effect confined to Europe and the States? (Ah, looks at graffs, yes it was but I see what you mean...)