资源环境科技发展态势分析平台

The Antarctic ice sheet (AIS) is a major contributor to current global sea‐level change and the largest potential source of future sea‐level change. Variability in AIS mass balance on a wide range of spatiotemporal scales obscures secular trends, increasing the uncertainty of projections. We introduce a novel approach for analyzing satellite gravity observations to estimate time‐varying mass change rates, and resolve the timescales and amplitudes of rate fluctuations. The new analysis resolves a higher degree of variability than expected over all AIS sectors. Quantifying rate fluctuations on a range of timescales, we demonstrate that loss from the West Antarctic Ice Sheet (WAIS) is characterized by a multi‐decadal trend, whereas variations of the East Antarctic Ice Sheet (EAIS) are dominated by substantial, short‐term accumulation changes that impact AIS mass balance as whole. These complex spatiotemporal variabilities highlight the need to include stochastic processes in estimates of loss rates.