That’s a new one to me! How bizarre!!
It is similar to an issue I noticed that the halo (glow size) around lights gets bigger the higher above sea level they are and the transitional ground effect I. Helicopters is also amplified the higher you are.
It could perhaps be connected in some way. Like the globe is not perfectly round and the details / effects are based off of some actual centre point of the planet. No idea how they really calculate the sphere of the globe though!
It’s more complex than it looks I bet, to get a planet into a game lol