I do actually use monthly snow/ice cover images in both projects! They're in the repo for the live clouds service [0].

I created them using the monthly images you linked combined with the Blue Marble "Land Surface, Ocean Color and Sea Ice" image [1]

[0] https://github.com/matteason/live-cloud-maps/tree/main/stati...

[1] https://visibleearth.nasa.gov/images/57730/the-blue-marble-l...