The Antarctic discovery is touted as the “first direct observation” of the planet’s ancient climate conditions. Researchers led by Princeton University in the US extracted two million-year-old samples ice in the remote Allan Hills of Antarctica. The Antarctic core samples contain pristine samples of trapped greenhouse gases – prehistoric bubbles of carbon dioxide (CO2) and methane (CH4).

The researchers are convinced the ice cores represent untouched snapshots of the Earth’s climate from a time before man ruled the world.

According to Dr Yuzhen Yan, who led the Antarctic study, the discovery paints an overall picture of changes in the climate.

He said: “You don’t get a sense of how things changed continually, but you get an idea of big changes over time.”

The discovery was presented in the journal Nature this month.

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