Simulation-Based Inference of Surface Accumulation and Basal Melt Rates of an Antarctic Ice Shelf from Isochronal Layers ...

The ice shelves buttressing the Antarctic ice sheet determine the rate of ice-discharge into the surrounding oceans. The geometry of ice shelves, and hence their buttressing strength, is determined by ice flow as well as by the local surface accumulation and basal melt rates, governed by atmospheric...

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Bibliographic Details
Main Authors: Moss, Guy, Višnjević, Vjeran, Eisen, Olaf, Oraschewski, Falk M., Schröder, Cornelius, Macke, Jakob H., Drews, Reinhard
Format: Report
Language:unknown
Published: arXiv 2023
Subjects:
Online Access:https://dx.doi.org/10.48550/arxiv.2312.02997
https://arxiv.org/abs/2312.02997
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Summary:The ice shelves buttressing the Antarctic ice sheet determine the rate of ice-discharge into the surrounding oceans. The geometry of ice shelves, and hence their buttressing strength, is determined by ice flow as well as by the local surface accumulation and basal melt rates, governed by atmospheric and oceanic conditions. Contemporary methods resolve one of these rates, but typically not both. Moreover, there is little information of how they changed in time. We present a new method to simultaneously infer the surface accumulation and basal melt rates averaged over decadal and centennial timescales. We infer the spatial dependence of these rates along flow line transects using internal stratigraphy observed by radars, using a kinematic forward model of internal stratigraphy. We solve the inverse problem using simulation-based inference (SBI). SBI performs Bayesian inference by training neural networks on simulations of the forward model to approximate the posterior distribution, allowing us to also quantify ... : Submitted to Journal of Geophysical Research: Earth Surface ...