Question about superatmospheric mesas.

[Turnpikelad]

I'm working on a worldbuilding project right now for a roleplaying game I intend to run sometime. The most unique thing about this world is that due to the flow of a sort of telluric energy, the magnetic poles of the planet (around 19 degrees away from the rotational north and south poles, like Earth) have tumesced out into great mesas that protrude beyond the atmosphere, probably about 25000 meters above sea level. These mesas are pockmarked with craters like the surface of the moon, and since the atmospheric pressure decreases by 1/2 every 5000 meters the atmosphere on the top is about 1/32 as thick as it is at sea level. Perhaps there is a little bit of lichen, but not much else can live there.

I wonder if you guys could help me back up a few assumptions I've made about how this would affect the climate and geology of the world.

-I'm thinking that cold air would be rushing downhill from the top of the mesa in a constant turbulent wind, creating persistent glaciation on the slopes that carves them into jagged mountain ranges. On the side of the mesas adjacent to the rotational poles, the glaciers would merge into the polar icecaps.

-Especially if the mesa was adjacent to a large ocean (like the northern one), the cold air coming down off the mountain and the warm air blowing in from the sea would create frequent and terrible storms, so that the mesa itself is usually obscured when viewed from sea level.

-The constant wind coming off of the mesa, the cold temperature and the moisture from the ocean would create a harsh, dense landscape- like Chilean Patagonia- in the land between the mesa and the ocean.

-The civilization that the players come from is itself not close to either of the mesas, and although naval expeditions have charted the coastline, the mesa was either obscured by storm or taken for a large chain of mountains.

-The other mesa is in the center of a large continent and is surrounded by high antarctic steppeland, populated thinly by hardy nomadic tribes. Although it is in a drier climate it too is ringed by glaciers and jagged mountains. It is also unknown to the European-analogue civilizations, although maybe the players could get some advice for how to survive in vacuum by talking with Uhrloni elders.

Does all this sound plausible to you guys? Could a 16th or 17th-century European civilization really be unaware of the existence of these things?

I've got a few sketches for maps, but no scanner and as yet no full-page world map. I'll try to get that done soon so I can show you what I'm talking about.

Edit: If this is in the wrong forum, I apologize; all the other threads seem to have maps attached