Major fall in CO2 levels dramatically cooled Earth’s climate 30 million years ago

New research suggests a 3C fall in temperature on land and in the oceans was a key driver of a pivotal transition from ‘hot greenhouse’ to a ‘cold icehouse’ world, writes Harry Cockburn

The fossilised remains of a tree stump in lignite deposits in Antarctica (Vittoria Lauretano)

Around 34 million years ago, a huge transformation in the Earth’s climate driven by a decline in the concentration of atmospheric carbon dioxide (CO2), turned the climate from a “warm greenhouse” to a “cold icehouse”, new research has confirmed.

However, this change, which occurred over millions of years, could be “partly reversed” over the coming centuries due to human-made greenhouse gas emissions, scientists have warned.

The transition meant that Antarctica, which had been covered by extensive lush forests, became the snow-bound wasteland covered with thick ice sheets we know today.