DOI: 10.5061/dryad.7sqv9s50x
title: Responses of Pine Island and Thwaites glaciers to melt and sliding parameterizations

description: Pine Island and Thwaites glaciers are the two largest contributors to sea
 level rise from Antarctica. Here we examine the influence of basal
 friction and melt in determining projected losses. We examine both
 Weertman and Coulomb friction laws with explicit weakening as the ice
 thins to flotation, which many friction laws include implicitly via the
 effective pressure. We find relatively small differences with the choice
 of friction law (Weertman or Coulomb) but find losses are highly sensitive
 to the rate at which the basal traction is reduced as the area above the
 grounding line thins. Consistent with earlier work on Pine Island Glacier,
 we find sea level contributions from both glaciers vary linearly with the
 melt volume averaged over time and space, with little influence from the
 spatial or temporal distribution of melt. Based on recent estimates of
 melt from other studies, our work simulations suggest that melt-driven
 combined sea-level rise contribution from both glaciers is unlikely to
 exceed 10 cm by 2200. We do not include other factors, such as ice shelf
 breakup that might increase loss, nor factors such as increased
 accumulation and isostatic uplift that may mitigate loss.
description: # Responses of Pine Island and Thwaites glaciers to melt and sliding
 parameterizations
 [https://doi.org/10.5061/dryad.7sqv9s50x](https://doi.org/10.5061/dryad.7sqv9s50x) ## Sharing/Access information This archive contains data related to a paper currently in revision at the Cryosphere: [https://egusphere.copernicus.org/preprints/2024/egusphere-2023-2929/](https://egusphere.copernicus.org/preprints/2024/egusphere-2023-2929/) Icepack/firedrake ([https://icepack.github.io/](https://icepack.github.io/)) must be installed and the firedrake environment must be activated. The forward and inverse code is at [https://github.com/fastice/icesheetModels](https://github.com/fastice/icesheetModels) It will require: [https://github.com/fastice/modelfunc](https://github.com/fastice/modelfunc) The results are in the following 7 directories (each with a README with further detail not given here) **forwardModel:** With directories and a script to run the forward model **forwardModelInputs**: The SMB file needed or the forward model (see manuscript for sources) **inversion**: Contains RCF-Inversion and Weertman-Inversion with scripts to run the inversions and a directory with all of the input data. **meshes**: meshes and an example reader. **randomMeltFunctions**: This directory contains the .yaml files with the melt realization parameters used in the simulation. Also included are example Python routines to compute the melt from the parameters and to generate new parameters. This directory also contains a file with several depth-parameterized melt functions from the literature (see manuscript for details). **meltRegions**: Masks to define which areas belong to which ice streams for tabulating melt on each ice shelf (e.g., so the melt for each shelf can be normed individually). **Code**: This directory contains the code for the basin scale model. Firedrake needs to be installed and activated to use this code.