Question

How might upward growth of cities be a better choice than outward growth?

Answer 1

Developing vertically rather than horizontally may be beneficial because this reduces the amount of land the urban area covers.

Explanation:

Developing vertically rather than horizontally may be beneficial because this reduces the amount of land the urban area covers. Expanding horizontally (building more structures and buildings) requires converting the surrounding environment to urban area. This surrounding environment may be forest, desert, grasslands or other types of land but replacing these ecosystems with urban area requires destroying or at least degrading these ecosystems.

Even in instances when area surrounding urban environments is anthropogenic, such as agricultural area, replacing crops with buildings increases our carbon footprint. If we built cities that are more vertical, then we could also reduce transportation costs and pollution compared to horizontal costs.

One person's idea of a vertical city:

You can read more about vertical cities here.