The Cost of Urbanization
From the onset of the Industrial Revolution to the current day, urban areas have been steadily growing as people flock to cities for greater opportunities. But unbeknownst to many, such opportunities can come with a price of global magnitude. Urbanization insinuates a much more insidious issue than initial illusions may imply.
The process of urbanization consumes arable land, threatens natural ecosystems, and unnaturally affects the climate. As cities overtake vegetation and native habitats, urban growth will contribute more heavily to global CO2 emissions (“Environmental Impacts of…”). Moreover, expanding cities often contribute to deforestation, displacing wildlife and threatening biodiversity. The congregation of humans and human activity also affects animals’ behavioral patterns and interspecies connections (“Urbanization”). Overall, Urban populations consume more resources and energy compared to rural populations, causing detrimental effects.
However, human migration doesn’t stop there. Humans sometimes tend to disperse outward from urban areas to low-density suburbs. This movement, known as urban sprawl, is characterized by leapfrog development. This is when developers favor cheaper land further away from urban areas over land adjacent to existing communities. Urban sprawl is also tied to large lot housing units, leading to low-density dispersion. Because homes are so spread apart, urban sprawl consumes enormous amounts of land, much of which was previously productive. Furthermore, the increased distance between notable places leads to a heavy reliance on automobiles, which contributes to decreased air/water quality and high energy use. Productive time is eaten up by driving, adding to sprawl’s pitfalls. Urban sprawl can also increase the risk of flooding and damage natural habitats.
One of the better-documented consequences of urban areas is the development of urban heat islands. Within cities, buildings and roads absorb and reemit more heat from the sun compared to natural elements such as trees or water. Heat generated from human activity is also a contributing factor. The heat is trapped by buildings, where cooling wind cannot reach. This results in an urban area with extremely high temperatures relative to surrounding areas. In some cases, day temperatures can rise up to 7 °F above surrounding areas. Urban heat islands drive up the demand for air-conditioning, causing electricity use to rise. Because much electricity is sourced from fossil fuel plants, this corresponds to a substantial uptick in air pollution and greenhouse gas emissions. Water is not exempt from urban heat islands’ effects, either. As water temperatures increase, hot stormwater runoff eventually runs off into natural bodies of water, home to aquatic life. For aquatic wildlife, the abrupt increase in temperature is debilitating and can even result in death (“Heat Island Effect”). Urban heat islands are closely related to urban sprawl, as sprawling cities cause higher temperatures (Tillett). Oftentimes, heat reaches extreme levels that can be fatal for those that are vulnerable.
The most cited way to combat the urban heat island effect is simply to plant and grow more trees to provide cover and shade. Green vegetation can even be planted on roofs, which reduces air temperature. Alternative methods include using reflective materials (that reflect heat energy rather than absorb it) and improved ventilation systems (Mirzaei). On a larger scale, environmentally conscious city planning can alleviate many negative effects. Individually, we can positively influence the environment by planting vegetation and seeking out energy-efficient products.
One novel way to reduce the environmental impact of urban centers is city planning centered around walkability and public transportation. As of now, cars are the most used form of transportation, releasing tons of greenhouse gas emissions each year. If we were to restructure cities so that urban areas became more compact, it would be much easier to walk from place to place, thereby reducing the need to drive. This would be achieved by decreasing the distance between places of interest, such as schools or stores. Cities can also become more pedestrian-friendly through the construction of wide sidewalks and safe intersections. The transition from driving to walking would introduce a multitude of benefits, including decreased air pollution, reduced land use, decreased noise pollution, limit land use, and lowering the urban heat island effect. Furthermore, walkable cities would allow for daily exercise and a greater connection with nature. Beyond the environmental effects, walkable cities will also save trillions of dollars due to the lowering of car operation costs (“Walkable Cities”).
By combining governmental legislation and individual effort, urban centers will become thriving communities without the pollution and increased temperatures currently associated with cities. Our conjoined effort will rely on a global understanding for a need to change. Without awareness and advocacy, urbanization will continue to mar natural ecosystems. It is therefore important to make our voices heard within our communities and educate others on the dangers of urbanization.
Brody, S. (2013) The Characteristics, Causes, and Consequences of Sprawling Development Patterns in the United States. Nature Education Knowledge 4(5):2
“Environmental Impacts of Urban Growth.” Seto Lab, Yale University, https://urbanization.yale.edu/research/theme-4.
“Heat Island Effect.” Environmental Protection Agency, 6 June 2022, https://www.epa.gov/heatislands.
Mirzaei, Parham A. “Recent Challenges in Modeling of Urban Heat Island.” Sustainable Cities and Society, vol. 19, Dec. 2015, pp. 200–206., https://doi.org/10.1016/j.scs.2015.04.001.
Tillett, Tanya. “Temperatures Rising: Sprawling Cities Have the Most Very Hot Days.” Environmental Health Perspectives, vol. 118, no. 10, Oct. 2010, https://doi.org/10.1289/ehp.118-a444a.
“Urbanization.” Understanding Global Change, https://ugc.berkeley.edu/background-content/urbanization/.
“Walkable Cities.” Project Drawdown, https://drawdown.org/solutions/walkable-cities.