Effects of seasonal variability of accumulation on yearly mean delta O-18 values in Antarctic snow

The annual mean oxygen-isotope content of Antarctic snow is strongly influe nced by the seasonal variability of accumulation. Since the annual mean del ta(18)O value is frequently used to derive mean annual temperatures from ic e cores, changes in atmospheric circulation pattern can lead to large error s in the deduced temperature record. At the German Antarctic wintering base , Neumayer, accumulation measurements have been carried out continuously ov er the last 16 years. Weekly readings of accumulation stakes combined with snow pits and shallow firn cores are used to investigate the influence of t he seasonal, variability of accumulation on the annual mean delta(18)O valu es and to estimate the possible error in the determination of annual mean t emperatures from ice cores by using the oxygen-isotope record.