He's helped examine deep-sea drill cores to try to track our planet's history in terms of carbon dioxide . One of the signals we thought we would see as we go into the major glacial epoch, about 14 million years ago, that there would be a big drop in carbon dioxide concentration in the atmosphere. It's well known that carbon dioxide in the atmosphere can trap heat near Earth's surface. So, going into an ice age, you'd expect to see less of it. But the team measured an increase in carbon dioxide as Earth slid into the last ice age.
World climate is complex . . .
You know, geologists, we like to find single explanations. . . But as we all really know, the Earth is much more complicated, and there are probably a variety of forces that come into play to produce these events. Special thanks today to NASA 's Earth Science Enterprise. I'm Joel Block for Earth and Sky.