20-Year Prospect
Surprisingly, cartography in the long run is looking pretty good. Employment is supposed to go up by 20% in the next twenty years—which, in case you're wondering, is much faster growth than the average career (source). This may seem surprising, but when you think about it, it makes sense. We'll always need maps. What if we discover a new planet? Someone has to map it out. And, like, what about outer space? Why can't we map that?
In the interest of keeping it real, though, we have to warn you that even though there is expected to be major growth in this career, it'll still be extremely small. For example, only about 17,500 people are employed as cartographers (source). That means a 20% growth is only about 3,500 jobs. Still, it's something. And the growth in this field has been consistent which means it'll probably keep expanding—and offering you opportunities to move upwards.