Ken at Chicago Boyz makes an excellent observation with regard to flying cars: they aren't meant to operate over cities, they're mean to replace cities.
For all of these purposes, the flying car serves not as a means of traveling within a city, but as a substitute for the city itself! Instead of shortening the distance between people and enterprises by crowding them into a city, the skycar shortens the travel time while allowing the people themselves to live hundreds of miles away from their jobs, their friends, and their favorite shops. A few dozen houses may be clumped together in a single clearing, or a single house may stand on its own, but in either case small neighborhoods and single office buildings/strip malls/large stores will be surrounded by miles of wilderness, and people will spend most of their time endangering nothing but trees or grass if they happen to suffer mechanical failure, and enjoying plenty of space between themselves and the nearest fellow traveler.
He also observes that decentralizing our population will make our country more resistant to terrorist attacks (even nuclear weapons). Not to mention the potential environmental benefits to be had, and the psychological benefits of lower population density. I suspect most people would live in town-sized clusters of 2,000 to 5,000 people, rather than the tiny villages Ken describes, but I agree that the megalopolis may eventually be a thing of the past.
Well, something has to change. Cities are either going to grow outward and become less dense, grow up and become more dense, or grow outward and remain dense. Smaller cities may grow to bump into bigger cities, creating a new metropolitan area that will do one of the things I mentioned.
Michael, color me a bit skeptical. Cities are not only useful from a practical perspective, but for a large number of people they're useful from a lifestyle perspective. A lot of people (particularly young ones) have absolutely no desire to live in small towns.
Mark, most of those are already happening and have been for quite a while now. I think the only "change" is the number of what we consider "large cities" and the number of people that live in them. More statistical change than structural.
What's already happening depends a great deal on the specific area in question. Whether it's Japan with cities growing upward or cities in uncrowded areas of America giving in to urban sprawl... different cities are doing different things.
Mark, no disagreement there. I guess I'm just confused as what you mean by "has to change"... I assumed you meant inevitability, but the inevitabilities you mention are already happening. Did you mean that you believe it ought to change (away from what you describe) and that the status quo is unacceptable? If so, I (mostly) disagree, but can't really respond since I don't know why you believe that.
The "has to change" part was in response to MW's last sentence: "the megalopolis may eventually be a thing of the past."
I got that much, I'm just still not sure whether you're saying things ought to change or whether or not the retiring of the megalopolis is inevitable. If the former, see my last comment. If the latter, I don't see how it has to change since cities have adapted to the growth your talking about with success. Until it starts failing (which I don't see happening. Once Metropolis starts running out of room, Central City will start growing to capacity, and so on), I suspect very little will change except for numbers (and, in some cities, a shift towards more self-sustaining suburbs and less comparitively less commuters).
It was the latter.
Cities will continue to change and adapt.. no question of that. What's not clear is what those changes and adaptations will result in. Cities in Japan, for instance, have little options; they pretty much have to grow up or start converting near-shore water into usable land. The problem with either of those options is that as you go further and further up, costs and design challenges increase exponentially or, in the case of converting water to usable land, adding existing structure types onto this newly-created land will be comparatively inefficient.
Here in America, though, everything will depend on the overall health of the city. Generally, the trend is away from huge centralized populations toward the same number of people over a larger area. There's a limit to how many people can afford to or want to live right in the middle of downtown NYC, for example. This suggests that the fringes of major cities will experience more growth than the central areas... or will continue to. At some point, these cities will not resemble what they once were. There won't be a stark contrast between rural and urban.
I think people want to live within 20 minutes of everything they regularly participate in. Flying cars would expand the 20-minute range and allow for less dense cities, that's all. Eventually, cities may not resemble what we consider to be "cities" at all.
Michael, what is environmentally friendly about it? We can see just from the introduction of the car the tendency of cities to sprawl, which directly results in the need for a car to get anywhere. Places like Dallas-Fort Worth, for example, are so spread out that any place you might like to go will be at least a mile away - too far for most people to walk, if there were even sidewalks. The entire metroplex is swathed in a web of highways, and now it's too late to put in any kind of public transportation because where would the bus drop the passenger off? Four miles between destinations? Flying cars will need fuel too, probably more fuel than do regular cars. And the proposal to spread out destinations (thereby consuming more fuel) is supposed to be environmentally friendly?
You're assuming that the main reason cities are crowded is to minimize the distances that people need to travel. But that's only part of the problem. Population density creates a lot of different efficiencies, from trash collection to power lines to water pipes.
Americans are probably already spreading out as the economy shifts from goods to information. Some people like cities; some don't. It probably shifts with age. If you're single, the city probably seems full of exciting opportunities. But marry have have a child or two, and you start to see some big reasons to move to a more peaceful locale.
michelle: The problem with cities isn't the absolute amount of pollution, but that it's so concentrated. Spreading the pollution out over 10x the area at 1/10th the density would make it much easier for it to dissipate.
BB: True, there are efficiencies, but flying cars will reduce the value of some of those efficiencies and allow greater spread. As cost drops, even a bit, people will spread more and more. There are plenty of places that get water from private wells. Trash collection is tougher.
As transport gets cheaper and more convenient, populations spread. However, even with flying cars, I think the cost of transport will rise over the next half-dozen decades or so, as current oil-burning techonology is replaced with something... radical.
More importantly, improved communications reduces the value of transport. Visit your friends in virtual pubs, for the cost of a local phone call? No worries about taxi's at the end of the night! Already conference calls are often used in preference to moving delegates around the globe.
jez: Fossil fuels won't be replaced until there's something cheaper.
Until there's another way to hook up with chicks, people are going to go out with their friends in person.