800,000 years ago – 1000 years ago

Changes in past atmospheric carbon dioxide concentrations can
be determined by measuring the composition of air trapped in ice
cores from Antarctica. So far, the Antarctic Vostok and EPICA
Dome C ice cores have provided a composite record of atmospheric
carbon dioxide levels over the past 800,000 years.

Credits:

Bernhard Bereiter, Sarah Eggleston, Jochen Schmitt, Christoph Nehrbass-Ahles, Thomas F. S