Within the European Project for Ice Coring in Antarctica (EPICA) the deep EDML ice core was drilled in Dronning Maud Land, Antarctica, down to the bedrock. The drilling was finished in January 2006. The drill site was adjacent to the German summer base Kohnen station at 75.00°S, 0.07°E, and 2882 m a.s.l.. The length of the recovered core was 2774 m. The core has been well dated down to 2415 m depth corresponding to an age of 150,000 years BP. Thus, the core spans at least the period from the penultimate ice age to the Holocene. The stable isotopes of water/ice, δ18O and δD were measured to provide a temperature proxy. During the past glacial several Antarctic Isotope Maxima (AIM) can be observed, which are due to millennial climate change. Using the records of methane and δ18Oatm, both measured at the air occluded in the ice, from the Greenland NorthGRIP ice core and the EDML ice core, it was possible to synchronize these two cores. It became evident that the AIMs are the Antarctic counterparts of the 25 Dansgard-Oeschger events (rapid warming events) , documented in Greenland ice cores for the past glacial. Obviously, it is the bipolar seesaw effect connecting both hemispheres, with the Atlantic storing and transporting heat from South to North. Millennial changes through the Holocene, as archived in the EDML core, are much smaller and smoother. There is no evidence for a warming or increase of accumulation at the drilling site for the past 50 years.
Helmholtz Research Programs > PACES I (2009-2013) > TOPIC 3: Lessons from the Past > WP 3.1: Past Polar Climate and inter-hemispheric Coupling