Atmospheric CO₂ and climate from 65 to 30 ka B.P.

[1] Using new and existing ice core CO₂ data from 65 ∼ 30 ka a new chronology for CO₂ is established and synchronized with Greenland ice core records to study how high latitude climate change and the carbon cycle were linked during the last glacial period. Atmospheric CO₂ rose several thousand years before abrupt warming in Greenland associated with Dansgaard-Oeschger events, 8, 12, 14, 17, four large warm events that follow Heinrich events. The CO₂ rise terminated at the onset of Greenland warming for each of these events. Atmospheric CO₂ is strongly correlated with the Antarctic isotopic temperature proxy with an average time lag of 720 ± 370 yr (mean ± 1σ) during the time interval studied. The new data and chronology should provide a better target for models attempting to explain CO₂ variability and abrupt climate change.