Its a random seed for Continents and Islands, with the ability to control continent size recolor the land and water and cast random lighting.
Attachment:
ice_earth.png [ 896.38 KiB | Viewed 3103 times ]
Attachment:
normal_earth.png [ 481.77 KiB | Viewed 3103 times ]
GMIC gives it sphere mapping ( I had to use 2.10 for this since 2.99.19 doesn't have GMIC)

Code, and Windows and Linux binaries inside zip.
Attachment:
earth_plugin.zip [88.42 KiB]
Downloaded 107 times
LOCATION TO PUT BINARIES
Windows C:\Users\(USERNAME)\AppData\Local\gegl-0.4\plug-ins
Linux /home/(USERNAME)/.local/share/gegl-0.4/plug-ins
Linux (Flatpak includes Chromebook) /home/(USERNAME)/.var/app/org.gimp.GIMP/data/gegl-0.4/plug-ins
then restart GIMP go to GEGL Operation and look for "Earth" if you are in 2.99.16+ look for Filters/render/fun/earth