This award is for support of a study to establish a quantitative nuclear method for determination of Antarctic ablation and accumulation rates and to provide correction factors for the carbon 14 ages of ice samples dated using trapped carbon 14. Recent studies have established the presence of cosmogenic in-situ produced carbon 14 in polar ice. In conjunction with estimated carbon 14 production rates, measured concentrations of carbon 14 per gram of ice yield, ablation rates which are in good agreement with the values determined from stake measurements. Similar studies to determine accumulation rates have been tested and the estimates are consistent with previous studies. This study will expand the preliminary work done to date in order to improve the 14CO and 14CO2 vacuum extraction techniques, by lowering blank levels and by obtaining more complete separation of 14CO and 14CO2.
