Model-based Error Grids and Satellite-derived errors for the World Magnetic Model (WMM)

1) The first part (*.mat) of the dataset contains the final processed error grids and global altitude profiles for the World Magnetic Model (WMM) as presented in the manuscript "Global geomagnetic model errors as a function of altitude and geomagnetic activity." The errors, combining both omission and commission sources, were calculated on a 3D grid (10∘×10∘ latitude/longitude) at 29 discrete altitude levels from the Earth's surface to 10,000 km. The dataset is binned by five levels of geomagnetic activity (G0-G4). These results were generated by synthesizing outputs from established models for the crustal (EMM), ionospheric (AMPS, DIFI), and magnetospheric (T89) fields. The data are provided in MATLAB .mat file format, with variables corresponding to each activity level and magnetic field component. 2) The second part (*.txt) of the dataset provides processed root-mean-square (RMS) errors of the World Magnetic Model (WMM) derived from satellite observations, used for validation in the manuscript "Global geomagnetic model errors as a function of altitude and geomagnetic activity." The data are sourced from the CHAMP, Swarm A, Swarm B, and CryoSat-2 satellite missions spanning 2005-2024. The processing methodology includes subtracting the relevant WMM version, binning the residuals by geomagnetic activity level (G0-G4), removing outliers, and correcting for secular variation (SV) forecast error using the CHAOS-8.2 model. The final data are provided as a set of ASCII text files, with values corresponding to the validation markers presented in Figure 5 of the associated publication.