Antarctic ice shelf analysis¶

This notebook iterates through all 164 Antarctic ice shelf and performs the following steps:

1) Extract all point measurements of bathymetry/bed topography¶

within 20 km of the ice shelf boundary
point measurements from IBCSO v2
point measurements for Bedmachine source data from simglebeam, multibeam, over ice seismic, over ice and airborne radar, and REMA elevations for exposed rock
IBCSO v2 swath bathymetry polygons are converted to point measurements with 100 m spacing
shown as black dots in subplot a below

extract gridded gravity disturbances from AntGG-2021 gravity compilation (subplot c)
correct it for gravity effects of ice, water, and topography to get the topography-corrected gravity disturbances (subplot e)
- use Bedmap2 grids of ice surface, ice base, and bed topography for calculation
calculate the standard-deviation of the topography-corrected gravity disturbance with the outline of the ice shelf

An example of the analysis applied to the Fimbul Ice shelf:

The results for each ice shelf, and plots of the results (as above), are all provided in the Zenodo archive:

constraint points: results/ice_shelves/<ice-shelf-name>_constraints.csv.gz
gravity anomalies: results/ice_shelves/<ice-shelf-name>_grav_anomalies.csv.gz
grids of distance to nearest bed measurements: results/ice_shelves/<ice-shelf-name>_min_dist.nc
plots of constraint points and distance to nearest bed measurements: results/ice_shelves/<ice-shelf-name>_constraints.png
Subplots of distance to nearest bed measurements, gravity error, gravity disturbance, starting gravity, gravity misfit, regional and residual misfit: results/ice_shelves/<ice-shelf-name>info.png

A table of the summarized results for all ice shelves are provided in results/ice_shelves/ice_shelf_gravity_stats.csv.

This notebook takes the results of the above notebook, and create the figures for the manuscript as well as some additional analysis.