This visualization graphically displays temperature and CO2 concentration in the atmosphere as derived from ice core data from 400,000 years ago to 1950. The data originates from UNEP GRID Arendal's graphic library of CO2 levels from Vostok ice core.

In this 6-part activity, students learn about climate change during the Cenozoic and the abrupt changes at the Cretaceous/Paleogene boundary (65.5 million years ago), the Eocene/Oligocene boundary (33.9 million years ago), and the Paleocene/Eocene boundary (55.8 million years ago).