Ep2: What Polar Ice Is Telling Us

Polar ice has a story to tell. Trapped in it are clues to the past -- dirt and dust, and air -- going back a million years . From this, climate scientists can figure out what was happening during past ice ages and warm periods. In each case, it all came down to carbon -- how much carbon dioxide was in the air.  And we're now at CO2 levels last seen in the Pliocene Epoch -- 2.5 to 5 million years ago, long before modern humans walked the earth.   Sure, we call ourselves homo sapiens, but glaciologist Martin Siegert says we're heading toward a 'stupid warm' future, and it's time to get smart.  He lays it all out here -- what's happening, what the ice is telling us, and what we need to do now.

Martin Siegert is a glaciologist with three decades of experience, including research in Antarctica., a professor, and co-director of the Grantham Institute - Climate Change and Environment, at Imperial College London (UK).