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arXiv · 2309.14373

Apparent ice accumulation rate in East Antarctica: Relation with temperature and thinning pattern

Abstract

We present here formal evidence of a strong linkage between temperature and East Antarctic ice accumulation over the past eight hundred kiloyears, after accounting for thinning. The conclusions are based on statistical analysis of a proposed empirical model based on ice core data from multiple locations with ground topography ranging from local peaks to local valleys. The method permits adjustment of the apparent accumulation rate for a very general thinning process of ice sheet over the ages, is robust to any misspecification of the age scale, and does not require delineation of the accumulation rate from thinning. Records show 5% to 8% increase in the accumulation rate for every 1${}^\circ$C rise in temperature. This is consistent with the theoretical expectation on the average rate of increase in moisture absorption capacity of the atmosphere with rise in temperature, as inferred from the Clausius-Clapeyron equation. This finding reinforces indications of the resilience of the Antarctic Ice Sheet to the effects of warming induced by climate change, which have been documented in other studies based on recent data. Analysis of the thinning pattern of ice revealed an exponential rate of thinning over several glacial cycles and eventual attainment of a saturation level.

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Radhendushka Srivastava, Debasis Sengupta, Prosenjit Ghosh. 2023-09-24. Apparent ice accumulation rate in East Antarctica: Relation with temperature and thinning pattern. https://arxiv.org/abs/2309.14373

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