I find ideas like this stimulating, if only because it shows some creativity: skyscraper farms.

Basically, the idea is to build multi-story enclosed greenhouses near the cities where most food is consumed, thus reducing the acreage required to grow the crops and the energy needed to transport them. Some of the work done by Columbia University suggests the “vertical farm” could produce at least twice as much energy as it consumes from burning the biomass wastes.

Part of the problem for me, and I imagine others here at Gristmill, is that it’s harder to think of a more concrete example of cutting humans off from nature. Take an eons-old human activity that has kept us close to the land and in touch with the earth, then box it up and close it off from everything but the cheap energy of the sun. (Let’s not get bogged down in the technical problems with this kind of building, which I assume are substantial.)

But then I think about Chernobyl, or the Korean DMZ. In the absence of humans, both have rapidly reforested and been recolonized by species of animals that in some cases haven’t been seen in those areas for generations. To put it another way, humanity’s regular everyday presence on earth is more disruptive than the worst nuclear disaster in history.

That includes farming, especially the way we do it for most of our food today. Just because farming is an old, old human activity doesn’t give it green legitimacy. Even if we go to low-footprint organic agriculture for everyone, everywhere on earth, if this idea were feasible I’d still think it was wonderful. (A 50-story farm would presumably replace an acreage 50 times the building’s footprint, right?)

Is it too much to say that environmentalists should all agree that nature exists independently of our interests? Nature does not exist to be farmed, any more than coal exists to be dug up and burned. Is it true, then, that there’s no such thing as “enough wilderness”? Does that not imply that human activity should be concentrated in as small an area of the planet as possible, leaving the rest wild? If we have to house and feed billions of people, doesn’t that necessitate ideas like this?

Crowding billions of people in to hundreds of megacities scattered across the planet sounds kind of nightmarish to me — rather Judge Dredd-esque. But it’s happening anyway, and cities are always and only what we make of them. I’m shocked to learn there are as many people living in greater Tokyo as there are in all of Canada. As crowded and expensive as I hear Tokyo is (I’ve never been, clearly), the environmentalist in me can’t help but think the world would be better off if Canadians learned to squeeze in to that kind of space.