Wednesday, 10 December 2014
Carbon Dioxide and the Ice Age
The 'Ice Age' is actually a long set of colder (glacial) stages and warmer (interglacial) stages.
In this graph, the jagged peak around 115,000 to 140,000 years ago is the Eemian Interglacial, when carbon dioxide was fairly high.
Interglacials often have local names - in Britain the Eemian is known as the Ipswichian.
After that, CO2 levels dropped and the Earth cooled into a long glacial stage, which ended around 12,000 years ago.
The cores mentioned in the key are ice-cores drilled from the ice of Antarctica.
MLO refers to the Mauna Loa Observatory in Hawaii.
Carbon dioxide levels are now rising much faster than normal.
Of course carbon dioxide is only one factor involved in glacial-interglacial stages.