Climate Change and Modernizing Urban Living

Catherine Pak
Thomas Jefferson High School for Science and Technology

This article was the 1st place winner in Teknos 2021 Summer Writing Competition

When phrases like “climate change,” “rising temperatures,” and “tipping point” are thrown around, many people’s first thought is fossil fuels, melting glaciers, or record-breaking summer temperatures. While all of these issues are important in their own right, one essential part of modern society that has significantly impacted the environment but has not elicited the same public outcries as the examples listed above is urbanization.

According to the World Economic Forum, 56.2% of the world’s population lives in urban areas. This percentage will rise as problems like brain drain, when significant amounts of educated individuals emigrate in search of financial opportunities, draw people towards more urbanized countries of refuge and money. Cities contribute significantly to greenhouse emissions, and a U.N. Habitat report from 2011 claimed that cities contributed up to 70% of “human-induced” greenhouse gas emissions despite comprising only 1-2% of the planet’s land [1]. Additionally, roughly 90% of cities reside near coastlines, so many are vulnerable to costly damages due to rising sea levels and stronger tropical storms caused by seawater thermal expansion and ice glaciers melting from rising temperatures [2].

*Figure 1. A map showing urban populations at risk of rising sea levels of 0.5 meters by the 2050s*

City residents experience the consequences of climate change in ways nobody imagined. People living in cities experience a phenomenon known as the urban heat island effect (UHIE) where urban areas tend to be hotter than the suburban or rural areas nearby. This increase in temperature can impact almost every aspect of city life, including building energy usage, electrical grid reliability, air pollution, and heat-related deaths [3]. Additionally, studies in Africa revealed the damaging environmental impacts of urbanization. Urban chemical pollutants (e.g. nitrogen oxides, heavy metals) from fossil fuels are toxic to animals and can cause increased molecular and tissue damage, weakened immune systems, and disease-related mortality. Additionally, noise and artificial light pollution created by cities disrupt natural habitats and natural habits, such as mating habits and territory behaviors [4]. Suburban residents and the local environment also suffer. Urban sprawl happens when residential areas develop around a central urban hub. Samuel Brody of Texas A&M University describes the negative impacts of urban sprawl with 6 characteristics: single-family dwellings, automobile dependency, spiraling outward growth, leapfrogging development patterns, strip development, and the undefined distinction between urban and rural areas [5]. While these characteristics are created through socioeconomic factors, the environmental impact urban sprawl has is undeniable. Greater automobile dependency leads to a rapid increase in air pollutants, and human health worsens by being exposed to said pollutants [6].

*Figure 2. A graphic description of the Urban Heat Island Effect [7]*

But there is one positive takeaway: despite being a large part of the problem, cities can also become part of the solution. Cities birth innovation, and a wave of sustainable solutions for urban life has started to take root. Modernizing city design is essential to create a more sustainable way of living in a continuously urbanizing society. “Urban forests” describe trees within a densely populated area, and these forests combat climate change by decreasing building energy costs and storing CO2 through photosynthesis. In the United States alone, these trees can capture millions of tons of CO2 annually while storing even more, and their shading and wind speed reduction counteract UHIE by reducing the amount of sunlight pavement absorbs. Additionally, $2 billion could be saved in energy costs if 100 million mature trees were planted in residential areas throughout the United States [8].

*Figure 3. A green space designed in Canada*

Generally, green spaces in urban areas positively benefit humans and the environment. Green spaces correlate with increased mental and physical health in humans, including reduced cardiovascular disease, stroke, and diabetes, regardless of their location globally [9]. While there may be several reasons why this correlation exists, many acknowledge that cities should incorporate green spaces in hopes of gaining these benefits.

The city-state of Singapore is a prime example of how urban design can effectively incorporate sustainability. To meet the U.N.’s 17 Sustainable Design Goals, Singapore has innovated many aspects of its city design. In the 1900s, Singapore focused on providing consistent energy with electricity and gas, but the city-state’s commitment to the Paris Agreement has pivoted the entire nation towards more sustainable energy. Solar power capacity in Singapore was estimated to cap at around 203 Megawatt peaks (MWp) in 2018, which could power hundreds of thousands of homes [10]. Singapore’s architecture integrates sustainability through solar panels, energy-efficient cooling systems, and green walls and roofs. Notably, Singapore’s Gardens by the Bay acts as a famous tourist attraction while being almost entirely self-sufficient. Electricity is created on-site by horticultural waste from across Singapore to reduce fossil fuel usage, and the buildings’ vegetation is cared for by the structures they are contained in. The Gardens’ conservatories reduce energy usage by selectively cooling down the lower levels via chilled water pipes within floor slabs and naturally letting warmer air rise up and expel [11].

*Figure 4. A graphic provided by the Singaporean government summarizing Gardens by the Bay [11]*

On a more individual scale, buildings themselves can counteract climate change with materials, structures, and systems that save money, resources, and energy. Natural ventilation has been one of the most common ways buildings achieve greater sustainability since it significantly reduces energy usage for cooling and heating. One of the most iconic structures in the sustainable architecture industry, Milan’s Bosco Verticale, is famous for its astonishing usage of greenery on the building. Roughly 800 trees and 5,000 shrubs comprise the walls of the apartment complex, and the vegetation absorbs 30 tons of CO2 annually, reduces UHIE by 2 degrees, and retains native biodiversity all in two towers. These plants reside in containers (1.10x1.10m for trees and 0.5x0.5m for shrubs), which are in turn kept on 3.3m terraces protected specifically to prevent root penetration, and an intricate irrigation system allows for consistent watering [12].

*Figure 5. Three views provided by Boeri Studios of Bosco Verticale’s green wall system [12]*

On the other side of the world, the Shanghai Tower is another architectural marvel in multiple ways. The Shanghai Tower is a result of the private and public sector collectively acknowledging that future design needs to keep sustainability in mind. The tower itself is twisted with rounded corners that reduce the building’s material use by 32% and allow it to withstand strong storms. Amazingly, the tower's structure is not even the most exciting part: two glass walls contain a tower with an atrium. The glass allows for natural light to flood the building, greatly reducing energy costs for lighting, and the outer glass skin ventilates the tower instead of traditional air conditioning units. Entire wind turbines on top of the building produce electricity on-site, which eliminates the need to transport electric power. Furthermore, the building collects rainwater and recycles grey water, used water from bathrooms and sinks, throughout the tower [13].

With more than half the human population living in urban areas, the way we design cities and modernize our architecture will greatly determine humanity’s future. While we are far from stopping the cascading effects humanity has set off in our planet’s environment, there is hope. Everywhere around us, humans continue to innovate towards complete sustainability, and we show no signs of stopping.

P.S. With the weather getting colder, I’m sure lots of students are feeling the mental effects of colder weather and darker days. When spring comes, I highly recommend you try visiting a green space - they seem to work wonders.

References

[1] UN Habitat. (n.d.). Global report on human settlement 2011. https://mirror.unhabitat.org/downloads/docs/E_Hot_Cities.pdf

[2] C40 Cities. (n.d.). Staying afloat: the urban response to sea level rise. C40. https://www.c40.org/other/the-future-we-don-t-want-staying-afloat-the-urban-response-to-sea-level-rise

[3] Pavement thermal performance and contribution to urban and global climate - References - Sustainable pavement program - Sustainability - Pavements - Federal highway administration. (2021, May 27). Federal Highway Administration. https://www.fhwa.dot.gov/pavement/sustainability/articles/pavement_thermal.cfm

[4] World Economic Forum. (n.d.). How is rapid urbanisation affecting city wildlife? https://www.weforum.org/agenda/2016/05/how-is-rapid-urbanisation-affecting-city-wildlife

[5] Brody, S. (2013). The characteristics, causes, and consequences of sprawling development patterns in the United States. Nature Education Knowledge. https://www.nature.com/scitable/knowledge/library/the-characteristics-causes-and-consequences-of-sprawling-103014747/

[6] Besnik, D. B. (2010, October). Urban sprawl, smart growth, and deliberative democracy. PubMed Central (PMC). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2936977/

[7] Mulhern, O. (2020, July 21). [Diagram]. https://earth.org/data_visualization/urban-heat-islands/. https://earth.org/data_visualization/urban-heat-islands/

[8] Safford, H., Larry, E., & McPherson, G. E. (n.d.). Urban forests and climate change | Climate change resource center. US Forest Service. https://www.fs.usda.gov/ccrc/topics/urban-forests

[9] Kumar, P., Druckman, A., & Gallagher, J. (2019, December). The nexus between air pollution, green infrastructure and human health. ScienceDirect.com | Science, health and medical journals, full text articles and books. https://www.sciencedirect.com/science/article/pii/S0160412019319683#s0010

[10] Towards a sustainable and resilient singapore. (2018). Ministry of Foreign Affairs. https://sustainabledevelopment.un.org/content/documents/19439Singapores_Voluntary_National_Review_Report_v2.pdf

[11] Sustainability efforts. (n.d.). Gardens by the Bay. https://www.gardensbythebay.com.sg/en/about-us/our-gardens-story/sustainability-efforts.html

[12] Bosco Verticale (Vertical forest), Milan. (2019, July 22). Greenroofs.com. https://www.greenroofs.com/projects/bosco-verticale-vertical-forest-milan/

[13] The Shanghai tower: Thinking about cities. (n.d.). Dartmouth Journeys | Teaching and Learning Sites at Dartmouth. https://journeys.dartmouth.edu/envs3eschafer/111-2/the-shanghai-tower/