CO2 and Global Cooling
It's often neglected that one of the most convincing arguments for the link between atmospheric CO2 and global warming is the paleoclimate record. Yet another big event in that climate record has now given it's evidence. This article cites new research showing that the formation of the Antarctic ice sheet 34 million years ago followed a 40% drop in atmospheric CO2.
On the plus side, this suggests that although the melting of Antarctica caused by anthropogenic emissions may flood big chunks of the world's population out of house and home, it may also open up a new continent for settlement. Of course the refugees may need to live in refugee camps for a few hundred thousand years during the transition.