James Hansen on Paleoclimate record and climate sensitivity
"We cannot burn all the fossil fuels." said Hansen at the AGU press conference, "If we burnt all of the fossil fuels we would send the planet back to the ice free state. We can't say how long it would take to get there but we know that the rate of change would be accelerating rapidly, and yet the governments and fossil fuel industry assume that we can go right ahead and go after all the coal and even begin to develop these unconventional fossil fuels like tar sands and tar shale and hydro fracking. That is a message which somehow we do not seem to have communicated as well as we need to."