A really clear presentation of swaths of climate change studies describing the impacts of the at-the-time-2007 expected range of warming 1-6 degrees by 2100. Combines model prediction studies and paleoclimate reconstructions to give a variety of regional and ecosystem/society depictions, and paints a bleak destructive view by 3 and certainly 4 degrees. More recent IPCC reports have extended plausible range of business as usual emissions to 8.5 degrees, and basically 2200 is beyond mentioning, so this was not light comfortable reading.