Explainer: How the rise and fall of CO2 levels influenced the ice ages
The Earth’s climate has been quite stable over the past 11,000 years, playing an important role in the development of human civilisation. Prior to that, the Earth experienced an ice age lasting for tens of thousands of years. The global average temperature was around 4C cooler during the last ice age than it is today. There is a real risk that, if emissions continue to rise, the world warms more this century than it did between the middle of the last ice age 20,000 years ago and today.
