Chill PillCommentary by Pete du Pont
September 20, 2007
There is both global warming and global cooling on the planet Earth. There always has been and there always will be, because temperature change is cyclical: The Earth's temperature oscillates up and down, ebbs and flows, over decades and centuries. Sometimes the earth warms, as it did in the Roman Warming period (200 B.C. to A.D. 600), the Medieval Warming period (900 to 1300) and in modern times from 1910 to 1940. And sometimes it cools, as it did in the Dark Ages (600 to 900); the Little Ice Age (1300 to 1850) and from 1940 to the late 1970s.