Complex Patterns of Antarctic Ice Sheet Mass Change Resolved by Time-Dependent Rate Modeling of GRACE and GRACE Follow-On Observations
Abstract
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 time scales 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 time scales, we demonstrate that loss from the West AIS is characterized by a multidecadal trend, whereas variations of the East AIS 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.
- Publication:
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Geophysical Research Letters
- Pub Date:
- January 2021
- DOI:
- Bibcode:
- 2021GeoRL..4890961W
- Keywords:
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- Antarctic Ice Sheet;
- GRACE/GRACE-FO gravity;
- ice sheet mass balance;
- stochastic mass-change rate