North ice pack and subs

[mitm001]

Subs need a way to discern more easily the terrain or whatever it is that sinks you up there when moving. Three times now I lost level 9 sea wolf to something invisible. The ice pack hides something, whatever it is and a high level sub should be able to detect it.

Additional context

[mitm001]

Here is an example of what I was sunk by.

[finnbear]

This is very much a valid issue, but it happens to be a duplicate of https://github.com/SoftbearStudios/mk48/issues/162

Until we fix it, ice travel is perilous (which is somewhat realistic)