|MadSci Network: Environment & Ecology|
Given enough money to build the actual structure, and enough energy to run it (such a structure would need to produce enough light, heat, and fresh water to support life), it is theoretically possible to build a small underwater city. However, it really wouldn't be possible for such a structure to be truly self-sufficient, because it wouldn't be able to produce its own energy. The only real energy source available on the sea floor would be geothermal heat- the problem is, the only place where this energy is readily available are near the spreading zones where tectonic plates diverge, which are also very lively areas, seismically speaking. Underwater volcanoes and earthquakes do not make for a good place to live!
Furthermore, for the city to produce its own food (as well as oxygen, though that could be created from hydrolysis of seawater, given enough electricity), it would have to culture plants of some sort. The recent failure of the Biosphere 2 project indicates (at least to me, some are less skeptical) that as yet we don't quite have the knowledge and technology to maintain an ecosystem capable of supporting humans in a self-sufficient way. Click here for a brief story, courtesy of the Detroit News, on some of the problems experienced during the Biosphere 2 project.
Hope that helps!
Rob Campbell, MAD Scientist
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