A detailed 2840 year record of explosive volcanism in a shallow ice core from Dome A, East Antarctica

A detailed history of volcanism covering the last 2840 years is reconstructed from the top 100.42 m of a 109.91 m ice core from Dome A (DA2005 ice core), East Antarctica. Using two known volcanic stratigraphic markers, the mean accumulation rate during the period AD 1260-1964 is found to be 23.2 mm w.e. a(-1), consistent with the previously reported accumulation rate at Dome A. This mean accumulation rate is used to date the entire core. Volcanic eruptions in the period 840 BC AD 1998 are detected as outstanding sulphate events. Seventy-eight eruptions are identified, with a mean of 2.7 eruptions per century. Comparisons with previous Antarctic ice-core volcanic records are made to assess the quality of this new DA2005 record. In terms of dates for volcanic events, the DA2005 record is in good agreement with previous records in the second millennium AD (AD 1000-1998). A series of volcanic signatures found in both the DA2005 record and several other Antarctic ice-core records in the first millennium AD (AD 1-1000) appear to validate the DA2005 record during this time period. For the older periods, direct comparisons are difficult between the DA2005 record and other Antarctic ice-core records due to the lack of well-dated stratigraphic horizons.