The Argument for Density, Part 1

Just to clarify here, we're talking about urban density, not the general physical concept of more mass in less space.

1) Sprawl causes deforestation. Whether it's cutting down trees to make room for new subdivisions, or the strip malls that feed them, or the roads that allow transit, or any number of other reasons, thousands of trees are cut down so the middle class can have a yard. Now, numerous practical studies like this one have shown that deforestation has various ill effects to the environment, including loss of biodiversity and desertification. Besides, forests are pretty.

2) In any physical system, the lower the surface area/volume ratio, the less energy transfer there is. Bergmann's Rule regarding the skin temerature of large animals is a biological example of this law. The converse is true, any mechanical engineer can explain that a radiator has to be a manifold with all that surface area to effectively transfer heat to the outside environment. Now, if you accept that population density is analogous to an inverse numerical representation of the surface area/volume ratio (at least for urban areas) then the lower the density, the higher the SA/V ratio, and therefore the greater the energy transfer. Rather than get metaphorical here, for this point we'll just leave it at: heating in the winter and cooling in the summer is more expensive and less energy efficient for low-density urban areas.

3) Transportation for dense urban areas is easier for people who don't insist on driving themselves. Mass transit becomes much more practical (and because it has less area to cover, it becomes easier to cover the area efficiently, leading to the virtuous cycle of people using it more, and so having public mass transit pay for itself.)

4) (This is more of a corollary to points already raised, but it builds on the others, so it gets its own number.) The costs of sprawl go beyond the obvious ones of deforestation, energy, etc. When subdivisions and the shopping centers that feed them are built, they are usually built using subsidies from the municipal government. The first form these subsidies take is that as part of an incorporated city, the city generally pays to build the roads for the expansions, as well as running utilities out to them. Now, if an individual buys a plot of land and builds a house, such niceties as electricity and sewers have to be handled by that individual. But if a developer buys a larger plot and builds lots of houses, the city pays for those niceties. In the case of the malls, cities will often subsidize not only the buildout of services and roads, but will also subsidize the companies opening shop with handouts like tax waivers and such. (Home developers are often given tax waivers as well, for that matter.) The cruel joke is that the taxes that are being waived are the same taxes that would otherwise (maybe, come close to, sort of,) pay for the services build-out, and the almost-immediate need for maintenance.

That's it for now. More later.
Your pal,
Dylan.