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Suppose a planet is covered with floating ice on top of water ocean and has no dry land.

Would it be possible to establish permanent settlements, cities?

Particularly I am interested in technologies combating

  • ice drift

  • melting of ice under the constructions and utilities

  • sinking of buildings due to snowfalls (as happened with the US South Pole dome)

  • strength of the ice sheet so to withstand big buildings

The following is true:

  • There is considerable ice drift, like that in Arctic.

  • There can be temporary clear water surfacing, but this is only for a time, and then ice moves to the place, there are no permanently ice-free areas.

I wonder, whether anchors could help against drift?

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    $\begingroup$ What are the technology and magic levels? Is this a recent development, was there an existing society which had to adapt to Iceworld, or are these interplanetary explorers? $\endgroup$ – minnmass Jan 23 '15 at 14:46
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    $\begingroup$ Where does the oxygen come from? Or what is the food chain based on? $\endgroup$ – Ville Niemi Jan 23 '15 at 15:32
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It's probably possible, but I wouldn't go about anchoring my ice city by use of metal anchors.

Instead, I'd try to encourage the formation of anchor ice, which is Ice that forms attached to the bottom of a body of water. If your city is based on a large patch of ice that's touching the sea floor, that particular part of the ice won't drift, and can be used as a platform for a geostationary city.

One way of triggering anchor ice formation would be to pour supercooled brine through holes in the ice. This exceptionally salty water can be cooled to below the freezing point of water, leading to a long icicle forming around the flow of brine, which eventually connects down to the bottom of the ocean, like this. If lots of such flows were created during calm weather when drift was at a minimum, they could provide sufficient anchoring force to stop drift.

Alternately, snow and ice could be piled up until the ice layer was thick enough to touch the bottom of the ocean. This would also create a tall 'dune' of ice above the surface of the ocean, proportional to the depth that the ice descends to. Since weathering action would slowly erode the top of the ice, it would need to be constantly replenished to stop the ice from floating up and away.

In either case, once anchored, structures known as stamukha would form on the edges of your city, providing additional anchoring as the ice sheets affixed to your anchor broke against the surrounding drift ice, eventually piling up into walls thick enough to touch the bottom of the ocean.

The heavy, thick ice below your city would provide a foundation on top of which structures could be built. However, it would be very difficult to go about mining for materials to create such structures. Most buildings will probably be crafted out of the most plentiful building material available: ice.

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  • $\begingroup$ Interesting! I wonder how one can use buildings built from ice! $\endgroup$ – Anixx Jan 23 '15 at 15:29
  • $\begingroup$ Many native peoples have been living in buildings built from ice for generations: en.wikipedia.org/wiki/Igloo. Body heat rises, so portions of the building can internally be above freezing. $\endgroup$ – ckersch Jan 23 '15 at 15:29
  • $\begingroup$ Also what if the ocean is very deep, so that the bottom is unreachable? $\endgroup$ – Anixx Jan 23 '15 at 15:30
  • $\begingroup$ I think you have to have an icicle miles wide to have any hope of the icecap not either breaking it off or grinding it down to nothing. Remember not even mountains are immune from glaciers and they are much slower. $\endgroup$ – bowlturner Jan 23 '15 at 15:46
  • $\begingroup$ As far as breaking my ice city loose from the bottom, I'd have to have an anchoring force that exceeded the compressive strength of the ice sheet pushing against it. Luckily, that's not terribly high, as evidenced by the constant formation of pressure ridges in the arctic. I would definitely expect erosion to be a problem, though. Luckily, my city is surrounded by plenty of ice for making repairs. Chopping it loose and trucking it into the city will be a major activity for my inhabitants. $\endgroup$ – ckersch Jan 23 '15 at 15:56
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If you want to stay in one place, you have to either travel over the ice (which you don't seem to like), under it (a terribly gloomy lifestyle), or through it (which has certain engineering challenges which I will now address).

I found an interesting reference book, Basic Coastal Engineering

It says that a vertical wall at the waterline can experience horizontal forces on the order of 200 to 300 Newtons per square centimeter. If you assume ice up to (for sake of argument) 6 meters thick this gives an overall force of something like 1700 tons per meter of width. This would take a pretty amazing amount of anchoring.

On the other hand, inclined plates can lift the ice, causing it to crack under its own weight and greatly reducing the horizontal force - for sake of argument, call it a reduction to 40 N/cm^2, or about 225 tons per meter of frontal width, which is much more tolerable. You need enough buoyancy to lift the edge of the ice, and enough depth to reach beneath it.

I think this would translate into something like either a long, narrow, very deep-draft barge or a SWATH-ship design (catamaran with thin vertical hulls standing on submerged pontoons). The barge would require more anchoring, but the SWATH has less reserve buoyancy. In either case, you would still need to occasionally deal with unusually thick ice, ie pressure ridges. This is probably best done by a watch force armed with depth charges or torpedoes - an underwater explosion is much more effective in lifting and shattering the ice. (Maybe replace the explosives with some sort of reusable high-volume compressed-air injector?


On the whole, this seems like a very large capital expenditure for very cramped living space. I think it is much more likely that people would live in portable (sliding) modules in a continuous migration against the ice movement, as suggested by James, or simply go with the floe (pun intended), as per bowlturner.

You might find Project Habakkuk interesting; this was a WW2 plan for an iceberg airfield stationed in the North Atlantic and prevented from thawing with a mixture of insulation and refrigeration. So long as the ice surface stays below -16C it will remain viable; in testing, 9m x 18m block was maintained through the summer by a 1hp motor.

In practice people would migrate to a far-North floe and construct a new town; ride it wherever it goes for the next 30 or 40 years until it becomes too expensive to maintain the refrigeration; then repeat the cycle.

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The world you are describing will not support permanent settlements (unless you redefine what a permanent settlement is. If you are talking a LAT/LON location...then no...but if you want a group of buildings and people that I think we can support and I think the answer here is small modular buildings.

Let me elaborate a bit,

  • These should be small enough that their weight will not crack submerge or otherwise impact the ice to a significant degree, this would likely require a little future tech, mainly lightweight building materials.
  • In the world you are describing the possibility of change seems pretty frequent and these modules should be able to float, basically each module is a boat.
  • Modules could be connected by the stuff they use to connect those accordion buses. enter image description here
  • So you have living modules, greenhouse modules, etc etc etc etc.

This gives you adaptable buildings that can survive the world you are on, course I hope you have a really good reason to send people to that planet as humans wouldn't have developed naturally on it.

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  • $\begingroup$ Similar to my post, Anixx didn't like it either... +1 $\endgroup$ – bowlturner Jan 23 '15 at 17:43
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Since the ice can melt and it's not a permanent iceworld like Hoth, then buildings need to be built on large 'floats' maybe even with the ability to move. The floats would also help keep the buildings from 'sinking' into the ice from pressure and can be moved to stay on top. Crops and such would likely need to be in green houses (also build on floats) because while you could build gardens on the ice with imported soil, (they have gardens in Alaska with permafrost underneath) you still need it warm enough to sprout and grow. This will need green houses.

Creating large (tall) structures would be unwise for many reasons because ice is not rock. The taller you build the more pressure melting ice underneath the building will be affected. It will actually be floating on a cushion of water.

You also have the problem of getting building supplies. You'd either have to mine under the ice (dangerous and problematic) or ship in all materials. The cost of shipping in the materials would likely encourage smaller more easily built structures that can be moved in needed.

EDT: It would be wiser to allow the ice to drift and stay with it than to try and anchor it. While it isn't as inevitable as a continent, it it hundreds of millions (billions?) of tons that want to move, either by tides and/or convection currents.

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  • $\begingroup$ Actually ice can be reenfoced by additional artificial cooling. They do so in permafrost areas. After such cooling the ice becomes very much like rock. $\endgroup$ – Anixx Jan 23 '15 at 15:12
  • $\begingroup$ "It would be wiser to allow the ice to drift and stay with it than to try and anchor it." - and how to avoid drifting to the South where ice can melt or become so thin that it cannot support the structures? $\endgroup$ – Anixx Jan 23 '15 at 15:14
  • $\begingroup$ @Anixx I put in that the buildings should be on floats and movable. That way they can adjust themselves. It would be much easier to move a city than to stop a huge planetary ice sheet from moving, on top of that you would be disrupting whatever ecosystem might exist by trying to do so. $\endgroup$ – bowlturner Jan 23 '15 at 15:16
  • $\begingroup$ What about anchoring just a small area as opposed to the whole planetary ice sheet? Could one isolate, cut some ice area and fix it? $\endgroup$ – Anixx Jan 23 '15 at 15:18
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    $\begingroup$ You can try to melt ice around your settlement, for instance. Or surround it with steel ice-breaking borders of streamlined form. $\endgroup$ – Anixx Jan 23 '15 at 15:23
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Look at how bases at tge South Pole are made with designs based on problems with previous iterations.

This page has a lot of details in downloadable documents, including Challenges that face South Pole architecture, which has major categories for

  • wind
  • ice flow
  • ice creep

I don't see it skimming through this, but I recall something about needing foundations that isolate the heat from the ground so the buildings don't sink! This is also the case for permafrost.

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