Comment by onlyrealcuzzo | Hacker News Reader

Comment by onlyrealcuzzo | Hacker News Reader

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A person's carbon footprint is directly related to their wealth/income. If 80% of wealth/income is in cities, this isn't surprising.

Further, the definition of "city" can include a lot of sprawl in places like Houston, Phoenix, and even Beijing and Tokyo.

Even further, can you cute your source? I'm skeptical of both numbers. And it would be very easy to cherry pick either side of these numbers.

For example, a lot of concrete is pored in cities to build mid/high rises. Concrete produces a fuck-ton of carbon. Is this amortized over the expected lifespan of the building? Where is the carbon cost accounted for? A lot of the carbon is emitted in rural areas. But is it all just lumped into the city because that's where it's used? That seems unfair. A lot of rural wealth comes from natural resource extraction used to build and power cities...

Most power plants and factories are outside of cities. Yes, they mostly power the city and produce goods for the city -- but their providing a lot of income/wealth to rural areas...

For citation here are two sources:

50% of population: https://ourworldindata.org/urbanization#how-urban-is-the-wor...

70% of emissions: https://www.c40.org/why_cities

This is based on the concept of a "consumption emission", which is an interesting concept. The point being that cities (especially western cities) have seen their emissions drop due to de-industrialization, but consumption has increased (hence your statement about carbon footprints correlating to wealth/income). To say that cities impacts are smaller when they just outsource all of their carbon impact is disingenuous.

From your source: It usually incorporates the population in a city or town plus that in the suburban areas lying outside of, but being adjacent to, the city boundaries.

GGP suggested that suburban living is greener. How does the 50%/70% support his point if cities include the suburbs?

> Further, the definition of "city" can include a lot of sprawl in places like Houston, Phoenix, and even Beijing and Tokyo.

Is it the case that you get to cherry pick which urban center is a real city based on how green it is?

The point is, there's likely a certain density at which it gets progressively more green to live in. If you're treating all cities equally, there's hardly a point in distinguishing between cities and small towns. There's not much of a difference between Omaha, Nebraska and Podunk, Kentucky. There's a gigantic difference between Manhattan and Yonkers.

I wouldn't be surprised if Dallas is "less green" than small towns in Italy, even adjusting for income/wealth. I would be surprised if the same is true when you compare to inner Tokyo (Shibuya).

One thing that would be interesting to know -- high rises can use a ton of energy to heat & cool. And the taller they get, a significant portion of the building is just stairs and elevators. I wouldn't be surprised if density gets "less green" at a certain maximum. Manhattan & Shibuya could very well be past that point.

>One thing that would be interesting to know -- high rises can use a ton of energy to heat & cool.

Sure, but how does that compare to the energy needed for lots of smaller buildings, which can provide the same floor space to the same number of people? I suspect the high rise is more efficient: it has far less surface area on the outside. The more surface area that borders the unheated/uncooled outside, the more energy you need to expend.

>And the taller they get, a significant portion of the building is just stairs and elevators.

Again, how does that compare to smaller buildings? Once you get past 1 floor, you're going to have to use space for stairs and elevators. You can't have a city with 1-floor buildings; the sprawl would be ridiculous.

>Manhattan & Shibuya could very well be past that point.

Have you been to Shibuya? Buildings really aren't that tall in Tokyo, especially in Shibuya. Remember, Tokyo (and pretty much all of Japan) is a highly tectonically active area, with frequent earthquakes. Manhattan has no earthquakes and has a huge layer of bedrock under it; it's basically the most idea place on the planet for building skyscrapers, except for being close to the sea (because of hurricanes, but these are rare because it's pretty far north). There are some reasonably tall buildings in Tokyo, but nothing like the 100-story behemoths in Manhattan.

Yeah, skyscrapers have a lot of stairs and elevators, but I'm pretty sure switching to a bunch of smaller buildings and replacing the stairs and elevators with roads and automobiles is not going to come out ahead on environmental impact.

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