Ocean reclamation and/or colonization

[Erik Mesoy]

Many of the world's bodies of water represent ecological wildernesses.

The main problem is that all the food sinks to the bottom - where there is no light, and life is challenging. In very shallow waters, plants - such as kelp - can span this distance. If the sediments are stirred up nutrients can go into solution, creating algal blooms, allowing animal life to exist. Elsewhere, life tends to be scarce. It seems like much of the planet's surface is going to waste.

Using such bodies of water for practical purposes would be easier if their surfaces could be employed.
One obvious possibility involves constructing platforms on their surfaces.

With a small body of water, it may be possible to stretch a skin over the entire surface. If this is possible, it is probably the simplest solution. The skin would consist of a network of cables and floats, to provide structural support - probably with a membrane suspended on or above the surface.

However, on larger scales, it may not always be practical to stretch cables right across a body of water.

Tesselated rafts are an alternative solution.


These would be constructed from waterproof, stiff material.
Water lilies are a proof-of-concept for the idea:



[...]

Full page.

I think this is a very interesting idea. I originally came across it in connection with a proposal to accelerate global warming to end the current technically-defined ice age going on on Earth. While I think that's risky at present and will have high transition costs, the basic ideas and technologies involved seem very interesting and worth pursuing. The page goes on to discuss aquaculture and floating cities, which raises a number of questions about naval territory ownership and the like.

How worthwhile and/or important do you guys think it is to be reclaiming oceans as habitable area? What sort of ramifications would this have? What suggestions would you make on how it should work, legally, politically and otherwise? Does it seem feasible in the near future (50 years or so)?

 

[The Last Conformist]

I think this is a very interesting idea. I originally came across it in connection with a proposal to accelerate global warming to end the current technically-defined ice age going on on Earth.

Why would one want to do that?

 

[Erik Mesoy]

Why would one want to do that?

To lower the risk of planetary reglaciation and to free up land for habitation that is currently inhospitably cold.

 

[Till]

This seems like an expensive and disaster prone proposal to address a non existing problem. Lack of land is not an issue right now, and i don't see it becoming one in the future. Humans can be stacked quite highly, as places like Hong Kong or Manhattan show.
We might run short on arable land eventually, but i would be surprised if off shore farms were cheaper than terraforming previously infertile land.

If a scenario would arise in which this proposal would be economically worthwhile, it would lead to a scramble between nations to claim as much ocean as possible, putting an end to the concept of "international" waters. Considering that resources on land are in decline and technology for deep sea drilling is getting closer to becoming reality, this might happen anyway.

 

[The Last Conformist]

To lower the risk of planetary reglaciation and to free up land for habitation that is currently inhospitably cold.

At the cost of sinking huge amounts of coastlands (proper deglaciation would raise sea levels by tens of meters) and launching unpredictable changes in weather patterns etc. I think I'd rather pass.

 

[Halcyon]

Such a skin would be too fragile to be practical, and the non-fragile alternative of earthmoving is too costly to be worth it in more than a few, small-scale cases. Generally the best place to build more land is on top of the land you already have.

Also consider whether or not you think humanity is already doing enough to rape the oceans to death. Not just the massive, massive overfishing, but things like agricultural fertiliser runoff causing algal blooms which asphyxiate everything larger than a single cell in areas larger than most countries, and just generally treating the sea like a zero-consequence infinite dump for every bit of crap (literally and figuratively) we can't be bothered to deal with sensibly. Things like that one get passed over simply because people don't live in the sea, and therefore don't notice when there's a floating debris field the size of Australia just sitting there, slowly photodegrading into toxic fragments.

So basically it's not that great an idea in practice.

 

[bhsup]

Peralandra!! I wonder if it would be doable to create such floating islands.

 

[FriendlyFire]

I demand ADAM and PLASMIDS

 

[El_Machinae]

The first thing that pops into my mind is that the Space Elevator is going to be ocean based, and so there will be pressure to grow a community around it anyway.

One consideration is the lack of nutrients. I'm working with old data (it might have changed), but I'm under the impression that the middle of the ocean is very sparse when it comes to life, because there are no nutrients. My old data recommended harvesting the water at the bottom of the ocean, because it should be terribly full of nutrients.

One wonders why this isn't done now. A few acres of floating net shouldn't be all that expensive, and it should be rather easy to grow food on that net. Mussel farmers do something like this already, but not on too large a scale.

 

[Synobun]

Why don't we just invest in Japan's self-made water islands and put farms on those?

 

[Erik Mesoy]

At the cost of sinking huge amounts of coastlands (proper deglaciation would raise sea levels by tens of meters) and launching unpredictable changes in weather patterns etc. I think I'd rather pass.

That's pretty much what I said:

While I think that's risky at present and will have high transition costs,[...]

One consideration is the lack of nutrients. I'm working with old data (it might have changed), but I'm under the impression that the middle of the ocean is very sparse when it comes to life, because there are no nutrients. My old data recommended harvesting the water at the bottom of the ocean, because it should be terribly full of nutrients.

This thingy seems to agree, with its suggestion of pipes that pump up nutrient-rich water.

 

[innonimatu]

How worthwhile and/or important do you guys think it is to be reclaiming oceans as habitable area?

Unnecessary and enormously wasteful. We're land creatures, not sea creatures. Living in the sea, or above the sea, requires an investment in resources which must come from the land. I very much doubt this investment would pay off, except for some very special places with worthwhile resources (we're getting oil from under the oceans).
As for food, there's enough trouble already with the use we're making of what the oceans naturally offer. I have no faith we could improve on things by trying to "farm" them - the conditions are too harsh for any elaborate large-scale construction there.

What sort of ramifications would this have? What suggestions would you make on how it should work, legally, politically and otherwise?

Assuming it actually could and would get done, then I guess we'd have first a scramble for the remaining international waters, then a long period of development (depleting many of our land-based resources on the process), and finally the "sea-people" would simply declare independence and proceed to have a go at their neighbors, wrecking their infrastructure in the process.

Does it seem feasible in the near future (50 years or so)?

If it's cheaper to use land, we'll continue using land.
It's cheaper to use land.

 

[LightFang]

A very interesting idea, Erik!