According to statistics, 56% of the global population lives in cities. The urban population is also expected to more than double over the next 30 years. By 2050, almost 7 in 10 people will live in urban areas.
Urban living is sometimes touted as more environmentally friendly than rural living. Proximity to shops and services can help reduce inhabitants’ carbon footprints and urban areas are less likely to house polluting industries.
But this is just a small part of the picture.
Are you wondering, “Why is urbanization contributing to pollution?”
Keep reading as we take a look under the hood to examine some factors around urbanization and pollution.
Urbanization and Its Demand for Man-Made Materials
Cities are infamous for pollutants like smog and car fumes, but the very structures that make up urban environments can also be pollutants.
Have you ever stopped to think of the sheer volume of man-made materials there are in the world? Cities are built almost exclusively of man-made materials.
Statistics show that in 2020, human-made materials (such as bricks, concrete, and plastic) surpassed the mass of all living matter on the planet.
The manufacture of human-made materials requires huge energy and natural matter inputs.
Man-made materials also aren’t part of the natural, ever-renewing cycle of growth and decay. Concrete takes about 50 years to break down. Plastics can take anywhere between 20-500 years to decompose.
To make matters worse, a lot of contemporary constructions aren’t built to weather the test of time. Instead of standing for hundreds of years, modern buildings of steel and glass only last for an average of 60 years.
When these buildings face demolition, they leave a massive mess of rubble and building waste in their wake.
Analysis shows that the construction industry produces roughly a third of the world’s overall waste. It’s also responsible for at least 40% of the world’s carbon emissions.
Sprawl Is Associated With Higher Per Capita Pollution
If all cities were perfectly planned, urban living could come with a lighter carbon footprint than rural living. The compact structure of cities can yield emission savings from higher densities of people, increased connectivity, accessibility, and better land use.
If the average person has on-foot access to most shops and amenities, this can be conducive to a low-emission lifestyle.
But the reality is that most cities are poorly planned. Urban areas tend to grow and grow, sprawling out into miles of suburbs. Reports show that suburban living is the worst for carbon emissions, as residents are forced to travel by car for most of their needs.
City sprawl is also a recipe for congestion. Congestion is a chronic, ongoing problem for most cities in the US and around the world. It’s also an issue that’s only predicted to get worse.
In 2017, the average person spent 41 hours in congestion, an 8% increase from 2010. That’s 41 hours sitting in traffic, burning fuel, and creating carbon emissions, to get somewhere you could have reached in a fraction of the time if the road was clear.
Urbanization Is Linked to Higher Rates of Consumption
Consumer behavior is another dynamic that plays a role in pollution due to urbanization.
Simply put, people living in urban environments tend to consume more. Urban living makes it easier to consume, as there’s more choice available.
Salaries also tend to be higher in large centers, which means more buying power. There might also be more “peer pressure” in urban areas.
If you live on a farm in Carolina, wearing a shirt from last year isn’t a big deal. If you’re working at a New York advertising firm, different story.
Urban Environments Are Conducive to Food Waste
When it comes to urbanization and pollution, food waste probably isn’t the first thing that jumps to mind.
But food waste is a huge source of carbon emissions.
Higher Food Appearance Standards
Most urban areas experience high levels of food waste. Often, discarded food is still fit for consumption when it reaches consumers.
One of the big reasons for this is urban consumer behavior. Urban consumers have more buying power and purchase more food from supermarkets with high food appearance standards.
Urban consumers live farther from where their food comes from. They’re also less connected with the natural process of growing food.
In other words, food that looks anything less than perfect is more likely to be discarded in an urban environment.
A High Carbon Footprint
To reach the urban consumer, food also has to travel through a longer supply chain than systems like farm-to-table. Farm-to-table food is likely to last far longer in the refrigerator than food from a supermarket that’s undergone cold storage.
Estimates state that it would take an area of farmland the size of Mexico to grow all the food that humans produce and don’t eat every year.
Agriculture also requires energy and water inputs and is responsible for land degradation and habitat loss. After harvesting, food receives further energy inputs for storage, transport, and preparation.
According to estimates, retail, food service, and residential sectors generated 66 million tons of food waste in 2019. Roughly 60% of this winded up in landfills.
Once food waste reaches the landfill, it generates greenhouse gases, contributing to the atmospheric CO2 overload.
Here at A Climate Change, we aren’t just interested in problems, we’re also interested in solutions. If you want to be a part of positive change, food waste is a perfect area to take action.
Besides trying to minimize food waste in your household, you can also make a difference by implementing a home composting solution. Composting food at home can help lower greenhouse gas emissions through improved carbon sequestration.
Cities Are Heat Traps
Not only do cities trigger higher rates of food waste, but they also trap heat, becoming urban heat islands. The heat island effect locks cities into domes of extreme temperatures.
Urban centers experience heat waves far more severely, and experts reckon that this phenomenon is only going to get worse.
Cities absorb warmth from the sun and produce their own heat. Air pollution, carbon emissions, tall buildings, and a lack of greenery and open space keep this heat from dispersing.
If temperatures rise high enough, they can become incompatible with human life. Extreme heat in cities isn’t just uncomfortable, it can also lead to health complications, including renal failure.
Not only can high heat levels be dangerous, but they can also drive up energy consumption and emissions.
As cities get increasingly hotter, inhabitants have to rely on climate control to maintain livable temperatures indoors.
Research findings show that electricity demand for air conditioning climbs between 1-9% for every 2°F increase in temperature. Countries like the US, where a majority of buildings have climate control systems, have the highest increases in electricity demand.
Unless you’re fortunate enough to have access to clean energy, the more electricity you use, the higher your carbon footprint will be. Here in the US, the power sector is responsible for 30% of the country’s carbon emissions.
Cities and CO2
Atmospheric CO2 is stoking the fire of global warming, driving extreme weather events, and causing sea levels to rise.
It has become such a pressing issue, that scientists are developing carbon removal technologies. But these technologies can only do so much, especially in the face of urbanization.
Compact, urban living is often posited as the solution to our carbon-intensive lifestyles. But like we said earlier, most urban areas aren’t designed efficiently. Very few areas allow residents access to most of their needs within walking distance.
Currently, cities account for over 70% of global CO2 emissions.
Given that only 50% of people live in urban areas, and a lot of industry takes place outside of cities, this is disproportionately high.
Cities Create Light Pollution
Besides their carbon footprint, cities are also contributing to skyrocketing light pollution. Light pollution due to urbanization might not sound all that serious, but it has a multitude of silent effects.
The planet is intrinsically tied to the natural circadian rhythm. When this is disrupted, it can have widespread impacts, some of which we might only discover in the future.
For one, light pollution can be detrimental to human health. It can also have deadly effects on wildlife, including amphibians, mammals, birds, and insects.
Light pollution is also tied to increased energy consumption, and with that, CO2 emissions.
Why Is Urbanization Contributing to Pollution? Now You Know
Urbanization isn’t showing any signs of slowing down, and it’s a huge driver of pollution. Urban areas trap heat, emit light pollution, require vast amounts of man-made materials, and are responsible for the lion’s share of our carbon footprint on the planet.
They also contribute significantly to food waste and are linked to higher rates of overall consumption.
If you were wondering, “Why is urbanization contributing to pollution?” this guide should give you a good idea. But, climate change and pollution are complex topics. There’s always more to learn.
If you want to stay informed on climate change, you’ve come to the right place. Tune into our podcast, where we interview leading environmental experts.