Compact cities produce fewer emissions than urban sprawl because they tend to offer better access to public transit and cycling and walking paths, have greater energy efficiency, have lower environmental costs for infrastructure, and allow for more green spaces. It is more expensive to construct and operate infrastructure that services sprawling communities than it is to serve compact ones (i.e. built upwards). According to the World Recourse Institute, one estimate suggests that a more compact approach to urban growth could reduce global infrastructure capital requirements by more than $3 trillion between 2015 and 2030. Building upwards can be socially difficult and unsafe but, with good design, it can also be socially beneficial and safer than urban sprawl/
Also, productive farm land is shrinking. Common sense inescapably says stop building on farm land, build upwards and limit population growth.
Bill Butterworth, Land Research Ltd, 22 November 18