Thaas outrageous, big Mammy refers. We had it as our journal club today, and the outcome was, no-one thought Hansen had done a convincing job.
The paper itself is confusing (“like being inside Hansens head”, as someone put it) and its not clear what its really supposed to be about. My pdf attempts to understand it. The only slide that won’t make sense is the last one; the 3-models-pic is number of AR4 models in the sresa1b scenario with sfc temperature in January above -5 oC. The conclusion of that (and other opinions in the room) is that substantial sfc albedo change is unlikely.
[Update: the original paper is here – thanks C -W]
[Update: there is some weirdness here about someone daring to reject Hansen for being 30 years out of date. But Phil Trans are not so bold -W]