Cities tend to get a bad reputation when it comes to the discussion of environmental problems. But really, there are many advantages to larger cities. That is why many researchers are advocating for the development of strategic, dense cities as a way to minimize negative environmental impacts of inevitable population increase.
1. Cities Have Higher Energy Efficiency
The household energy consumption in cities is much lower than that of surrounding suburbs. This is partly due to lifestyle and housing differences. Much of the city population lives in apartments where heating and air conditioning is much more efficient. Suburban households have a much higher surface area to volume ratio than apartments which provides more area for heat or air conditioning to escape. It is estimated that cities are about 25% more efficient than their suburbs.
2. Carbon Dioxide Emissions Per Person Are Lower In Large Cities Than In Suburbs
According to a UC Berkeley study, suburbs account for about 50% of all US household carbon dioxide emissions. Typically, as population density increases, emissions also increase, but at a certain threshold of about 3,000 people per square mile, the trend shifts and emissions per person is actually lower. This difference is mostly due to lifestyle differences in transportation between cities and suburbs. City dwellers tend to rely much more on public transportation systems and walking while in suburbs, people tend to rely on gas-guzzling vehicles.
3. City Dwellers Can Enjoy Local, Environmentally Friendly Food
There is a lot of research and development going on regarding city self-reliance in food production. A study in Cleveland ,Ohio suggested that much of the city's poultry and produce needs could be met by utilizing empty space such as rooftops and vacant lots to build greenhouses resulting in much lower transportation costs and environmental externalities.
4. Cities That Are Built-Up Are More Sustainable Than Those That Are Built-Out
New York city is a built up city, where population is much denser per square foot of land. Washington, D.C., on the other hand, is built out, having a much lower population density. This results in less public transportation use and fewer pedestrians than in built-up cities where more stores, restaurants, and workplaces are all within a few blocks from each other. It is for this reason, that many environmentalists, scientists, and city planners will advocate for the construction of strategic city nodes of denser population rather than urban sprawl.