Supplementary data to Frasson et al. 2024

Supplementary data and code for Frasson et al. 2024  accepted for publication in Solid Earth. The data consist of full snapshots of the geoids, topography, CMB heat flux, and composition at the CMB for the six cases of the study; the PCA outputs for the six cases; and movies showing the time evolutions of the outputs in the mantle convection models. The scripts can be ran on the snapshots to compute the principal component analysis (PCA) and the true polar wander (TPW).

The full snapshots are given in HDF5 format, with one file per time step. They can be found in the archives MF.zip and MC.zip for the MF model and the MC model respectively. The files contain:

• The fields in the physical space. The first coordinate is the latitude, the second coordinate is the longitude (dataset "data").
• The latitudes and longitudes associated with the fields (datasets "latitude" and "longitude").
• Some information regarding the snapshots (attributes "Time (Myr)", "Model", "Case", "Correction", and "Unit").

The files are called "name_xxxx.h5", where xxxx stands for the time in Myr before the end of the simulation.The names of the files are:

• qcmb: CMB heat flux
• geoid: Total geoid
• geoid_nolvv: No LVVs geoid
• topo: Topography
• prim: Composition at the CMB

The PCA outputs are given in HDF5 format. Each file has an "outputs" and a "grid" group. The "outputs" section gives:

• The average heat flux pattern. The first coordinate is the latitude, the second coordinate is the longitude (dataset "average").
• The list of patterns for each PCA component in physical space. The first coordinate is the latitude, the second coordinate is the longitude (dataset "pattern").
• The time-dependent weight of the components. The first coordinate is the time, the second coordinate is the component number (dataset "weights").
• The singular values of the components  (dataset "singular values").
• The time in Myr (dataset "Time").
• The component numbers (dataset "components").

The "grid" group gives the latitudes (dataset "latitude") and the longitudes (dataset "longitude") associated with the patterns.

Description of the movies:

• outputs_MF: As in Fig. 2 in Frasson et al. 2024.
• outputs_MC: As in Fig. 3 in Frasson et al. 2024.
• qcmb_MF: CMB heat flux in cases MF0, MF1, MF2, and MF* in a Mollweide projection. Black lines delineate the edges of basal chemical piles.
• qcmb_MC: CMB heat flux in cases MC0 and MC1 in a Mollweide projection. Black lines delineate the edges of basal chemical piles.

Description of the scripts

• PCA.py: Computes the PCA of the field stored in the path provided as argument for the given model.
• inertia.py: Computes the successive positions of the inertia axis. This script includes functions to rotate the outputs according to the positions of the inertia axis.