# Data fetched via HTTP from ['ftp://ftp.ngdc.noaa.gov/geomag/wmm/wmm2020/shapefiles/2025/WMM_2025_all_shape_geographic.zip']

# Data processed using the following steps:

unzip -j -d {output_dir} {input_dir}/WMM_2025_all_shape_geographic.zip *X_2025*

OGR_ENABLE_PARTIAL_REPROJECTION=TRUE ogr2ogr -lco ENCODING=UTF-8 -t_srs EPSG:3413 -clipdst {assets_dir}/latitude_shape_40_degrees.geojson -dialect sqlite -sql "Select Geometry, Contour, SIGN, \"INDEX\", CAST(Contour AS TEXT) || \" nT\" as label FROM X_2025" {output_dir}/X_2025.gpkg {input_dir}/X_2025.shp