This short video, adapted from NOVA, explains how Earth's position relative to the Sun might be responsible for the dramatic shift in the climate of what is now the Saharan nation of Djibouti.

In this video, a team of paleontologists, paleobotanists, soil scientists, and other researchers take to the field in Wyoming's Bighorn Basin to document how the climate, plants, and animals there changed during the Paleocene- Eocene Thermal Maximum (PETM). During this time a sudden, enormous influx of carbon flooded the ocean and atmosphere for reasons that are still unclear to scientists. The PETM is used as an analog to the current warming. The scientists' research may help inform our understanding of current increases in carbon in the atmosphere and ocean and the resulting impact on ecosystems.