Supplementary data files for landscape and ice sheet modelling - Gernon et al., 2026, Continental breakup-driven uplift instigated East Antarctic Ice Sheet formation

Ice sheet modelling PISM_files.zip contains: PISM_parameters.docx Document listing PISM parameters and input fields. make_pism_input_file.m MATLAB script to generate the netCDF for PISM. HR24_GHF_mean_PS.grd reformatted (reprojected and cropped) version of the Hazzard & Richards heat flux grid input to make_pism_input_file.m Landscape reconstructions GIS_files.zip contains: Raster *.tif files of landscape reconstructions at 2 Myr intervals from 100 to 36 Ma, and the 34 Ma basemap (from Paxman et al., 2019). Reconstructions are based on scaling the 34 Ma basemap using change in elevation (relative to 34Ma) estimated from our (conservative) Fastscape simulations, and are presented in fig 3(A) in the manuscript (reconstructions at 150, 100, 50 and 34 Ma), and movie S2. Vector shapefile outlining the area of interest (Area_of_interest.shp), used to calculate elevation profiles and summary statistics (mean and percentile elevation at increasing distance from COB) Fastscape Fastscape.docx Tables of input parameters for both the best fit (reference) simulation and uncertainty analyses, and brief summary of model boundary configuration and resolution. See methods in main manuscript for full description. Example_Fastscape_misfit_fn.txt misfit function for parameter tuning based on best fit to key features of the 34Ma topography, and plots in fig. S7 FASTSCAPE_OUTPUT_Reference_model_topo_160-34Ma.csv Fastscape output giving mean elevation (topography__elevation, meters) at distance x (meters) and time (years) for the reference model, as presented in fig. S4A. Note time and distance are in the model reference frame. Time is relative to the start of the simulation, with time=0 corresponding to 160 Ma, and the final step, time=126e6, corresponding to 34 Ma. The COB and initial plateau are at x=100e3 meters in the model reference frame. See methods and supplementary table S1 for full details and model parameters. XYpoint_data_scaled_elevations_area_of_interest.csv Reconstructed elevations at points on a 5 km raster grid, within the area of intererst (see shapefile in GIS_files.zip) Table comprises: X,Y coordinates (CRS: EPSG: 3031 - WGS 84 / Antarctic Polar Stereographic). dist_COB16: shortest distance from point X,Y to the 160 Ma COB line segment (km). t160 through t34: reconstructed elevation (meters) at times from 160 to 34 Ma. Note values at 34 Ma are taken from the 34 Ma basemap (from Paxman et al., 2019). Elevation_summary_stats_area_of_interest.csv Summarises change in elevation with distance from the COB for the area of interest outlined in fig. 2A (inset map) and 3A (topographic reconstructions) in the main manuscript (Area_of_interest.shp) dist_km: distance from COB in km. Time: timestamp (Ma). mean: mean elevation (meters) at given time and distance from COB. p_0, p_5, p_10, p_50 etc: percentile values for elevation (meters) at given distance/time. These data are presented in figs. 2A and S1, and movie S1: Modeled 2D landscape evolution for the region of interest from theDronning Maud Land escarpment to the Gamburtsev Mountains. These files are supplementary data for: Gernon, T.M., Hincks, T.K., Goodwin, P., Paxman, G.J.G., Brune, S., Rohling, E.J., Keir, D. & Braun, J. Continental breakup–driven uplift instigated East Antarctic Ice Sheet formation. Science, 392, eadz6758, https://doi.org/10.1126/science.adz6758 (2026). Reference for baseline 34 Ma topography: Paxman et al., 2019. Reconstructions of Antarctic topography since the Eocene–Oligocene boundary. Palaeogeography, Palaeoclimatology, Palaeoecology. Volume 535, 2019, 109346, ISSN 0031-0182, https://doi.org/10.1016/j.palaeo.2019.109346.