Oxygen Isotope Record from McMurdo Dome and its Relation to the Geological Climate Record of the Dry Valleys

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This proposed research will obtain a stable isotope climate record covering the Holocene (the last 10,000 years) and the last part of the last glaciation from a small ice dome near the head of Taylor Valley, South Victoria Land ("McMurdo Dome" about 77 40' to 77 50'S, 158 10' to 159 20'E). An independent time scale will be derived from an ice-flow model adjusted to the depth of the glacial-interglacial transition and to oxygen isotope-derived variations in accumulation rate down the core. Comparison of this isotope proxy climate record with a radiocarbon-dated proxy record of climate, derived from perched deltas, strandlines and moraines, in the nearby Dry Valleys allows a dual approach that could be crucial for the interpretation of both the oxygen isotope fluctuations observed in ice cores during the Holocene and the lake levels and ice margin positions during this time span. The location of the dome, just west of the Transantarctic Mountains, is expected to have been sensitive to changes in ice cover of the Ross Sea, but protected against direct influences of glacial-interglacial sea level rise. The dome's isotope record may, when compared with the Dry Valley glacial record, and with long East and West Antarctic isotope profiles from ice cores at Vostok, Dome C and Byrd Station will reveal the response of the East and West Antarctic Ice Sheets to the glacial-interglacial temperature increase and sea level rise.