8 glacial cycles from an Antarctic ice core

A new ice core from Dome C, East Antarctica, provides a climate record extending740,000 years back in time. This almost doubles the period covered by the Vostokcore. The new data confirm the Vostok data for the last 4 glacial cycles. The periodfrom 450 to 740 kyr before present was characterised by less pronounced warmth ininterglacial periods in Antarctica, confirming the pattern seen in marine sediments.The transition from marine isotope stage 12 to 11 exhibits both similarities and differencesto the most recent transition, but stage 11, sometimes seen as an analogue to thepresent (Holocene) interglacial, extends for a further several thousand years. Furtheranalysis of the core will show whether close coupling of greenhouse gases and climatecontinues into the earlier regime which has a different frequency and amplitudestructure. Completion of the drilling will offer a record of nearly a million years.