Jeremy Gratham: Now, for the data. Climate change damage accelerates. This is the famous chart you saw if you did with Al Gore. It shows that 180 parts to 300 parts per million of carbon dioxide. At the bottom there at 180 up from 0, we had ice ages in the popular parlance where New York 20,000 years ago was about a thousand feet deep in ice, larger, taller than the biggest building they have there today. At 300 parts or 280, we had the interglacials, four of them where we had an agreeable existence as we have today. Just for the record 75% to 80% of the time within the icy ages and only 15, 20% also were in the interglacials.