Underestimation of snow accumulation rate in Central Antarctica (Vostok Station) derived from stake measurements

Abstract

It is shown that the snow stake measurements in central Antarctica systematically underestimate the value of the snow build-up. Two methods for the calculation of the corresponding correction to the snow stake measurements at Vostok station are developed to take this underestimation into account. The first method is based on the Sorge’s law to calculate the rate of compaction of snow layers using the vertical profile of snow density. The second method is based on the direct field measurements of this compaction. Two independent methods for the estimation of the snow accumulation rate in the vicinity of Vostok station are also considered: geodetic data on the rate of snow layer sinking and glaciological data from snow pits. The most reliable estimate of the snow accumulation rate in this region is 2.26 ± 0.10 g/cm2 per year, that is 8 ± 4% higher than uncorrected values from snow accumulation measurements.