The EPICA (European Project for Ice Coring in Antarctica) Dome C drilling in East Antarctica has now been completed to a depth of 3260 m, at only a few meters above bedrock. Here we present the new EDC3 chronology, which is based on the use of 1) a snow accumulation and mechanical flow model, and 2) a set of independent age markers along the core. These are obtained by pattern matching of recorded parameters to either absolutely dated paleoclimatic records, or to insolation variations. We show that this new time scale is in excellent agreement with the Dome Fuji and Vostok ice core time scales back to 100 kyr within 1 kyr. Discrepancies larger than 3 kyr arise during MIS 5.4, 5.5 and 6, which points to anomalies in either snow accumulation or mechanical flow during these time periods. We estimate that EDC3 gives accurate event durations within 20% (2 sigma) back to MIS11 and accurate absolute ages with a maximum uncertainty of 6 kyr back to 800 kyr.

Timescale EDC3 for the EPICA Dome C ice core, both for the ice matrix and gas bubbles. The dataset gives the depth versus age timescale that has been adopted as official for the EPICA Dome C ice core. Depth refers to the official log depth of the drilling. EDC3 for the ice matrix (EDC3_ice) is described fully in Parrenin et al. (Climate of the Past, 3, 485-497, 2007). This timescale is based on an snow accumulation / ice flow model, which is further tuned with independent age markers. Gas ages are derived using a firn densification model, and are fully described in Loulergue et al. (Climate of the Past, 3, 527-540, 2007). The ages given here correspond to the scenario 4 of Loulergue et al. and where necessary can be referred to as EDC3_gas_a.

Supplement to: Parrenin, Frédéric; Barnola, Jean-Marc; Beer, Jürg; Blunier, Thomas; Castellano, Emiliano; Chappellaz, Jérôme A; Dreyfus, Gabrielle; Fischer, Hubertus; Fujita, Shuji; Jouzel, Jean; Kawamura, Kenji; Lemieux-Dudon, Bénédicte; Loulergue, Laetitia; Masson-Delmotte, Valerie; Narcisi, Biancamaria; Petit, Jean Robert; Raisbeck, Grant M; Raynaud, Dominique; Ruth, Urs; Schwander, Jakob; Severi, Mirko; Spahni, Renato; Steffensen, Jørgen Peder; Svensson, Anders M; Udisti, Roberto; Waelbroeck, Claire; Wolff, Eric William (2007): The EDC3 chronology for the EPICA Dome C ice core. Climate of the Past, 3, 485-497