Urbanization

When you think of urbanization, what first comes to mind? The tall skyscrapers of New York City or the crowded crosswalks from Tokyo? Throughout history, millions of people have moved from the country to cities for economic, social, and political reasons. Unsurprisingly, this urbanization is an ongoing global trend! More than half the world population currently live in urban areas, and it’s projected that almost 7 billion people will live in urban areas by 2050 (source).

Air pollution and fossil fuel usage are probably some of the first environmental impacts you’d associate with urbanization, and you’d be right to do so. But besides those, there are many other factors of urbanization that contribute to the overall climate crisis. Let’s watch the following video from the Science Museum of Virginia to learn about urban heat islands.

Q: What are the contributing factors of urban heat islands? Why are urban heat islands harmful?

Urban heat islands can be detrimental to human health, especially during heat waves, which are increasingly common. Check out this global map of the number of deadly heat days in different countries over time. Be sure to click on red and orange areas to see the heat anomalies and the deadly thresholds of that area.

• Heatwaves: Number of deadly heat days, interactive map from University of Hawaii at Manoa

Q: If you compare just the 2020 world map to the 2050 world map, what differences do you see? Can you think of possible causes for these differences?

It’s not a coincidence that the hottest areas also happen to be in the world’s most urbanized cities. As we’ve just learned, they are indeed related! Try thinking of solutions that cities can work towards. Then take a look at this Grist video and EPA article about the different steps that US cities have taken to diminish the urban heat island effect.

• Reduce Urban Heat Island Effect, EPA article

Q: Describe two solutions to urban heat islands that you learned about. Can you think of your own?

Thermal inversions

If you’ve ever gone camping or hiking in the mountains, you’d know by experience that the higher you go, the colder it gets. However, there are times when the exact opposite occurs - temperature increases as altitude increases. Thermal inversions, also known as temperature inversions, are natural phenomena in the atmosphere where the air above the ground is warmer than the air below it. Weird, right? Check out this video to see how thermal inversions occur in some of Utah’s cities.

As the video explains, the main problem with thermal inversions is the trapping of emissions and air pollution from urban areas, especially those nestled in a valley between mountains. The warm air acts as a lid, essentially sealing and condensing all of the toxic pollutants near the ground, leading to poor air quality for urban residents. The terrain prevents the trapped cold air from escaping and the surrounding mountains prevent winds from ushering in fresh air. The end result is nasty, stagnant air that is not only unpleasant to live in but also hazardous to our respiratory systems.

To add onto that, scientists have recently observed a pattern between climate change, thermal inversions, and “super pollution” events. It is possible that climate change is worsening thermal inversions, and vice versa. Read this article to find out more about this issue.

• Climate change has led to more temperature inversions and the rise of 'super pollution events', GreenBiz article

In any case, because thermal inversions are naturally occurring, there is not much that we can do to prevent them from happening. But we can take care of things on our end and continue reducing our carbon footprint. And who knows? Given the current rate of technological and scientific advancement, we may soon discover a long-lasting solution.

Photochemical smog

Everyone has a general idea of what smog is - usually a yellowish dense fog or haze blanketing cities such as San Francisco and Beijing. Let’s dive deeper behind the science of photochemical smog by watching this video.

Q: How are the secondary pollutants formed and how do these pollutants affect human health? What kinds of cities are the most vulnerable to photochemical smog (hint: their surrounding geographies)?

Tropospheric ozone, one of the main pollutants of photochemical smog, is potent to all plant and animal life. Plants like tobacco, tomato, and spinach, are sensitive and highly reactive to ozone. Therefore, photochemical smog has the ability to damage plant leaves, stunt growth, and increase vulnerability to disease. Studies conducted from 1980 to 1989 exposed the most important agronomic crops in the USA to varying concentrations of ozone (O₃). Below were their findings:

Q: What trends, if any, do you see in the graph? Which crop(s) lost the most yield and what implications does that have in our lives? What do you predict will happen in future years?

Remember the story from Unit 2 ("Why does climate change matter?") about Uruk and Anuradhapura? As a quick refresher, Uruk’s farmers chopped down their trees to make space for more crops and infrastructure. But without trees to filter their water supply, Uruk’s irrigation became contaminated and rendered the soil way too salty to grow agriculture. Contrastingly, in Anuradhapura, where trees were held sacred, their irrigation system ended up working with the surrounding forests and their population grew twofold.

This historical example shows us just how important trees are, especially as the most natural solution for smog and urban hotspots. Watch this video to learn the ways in which trees offer a better quality of life.

Q: Why is planting trees helpful in preventing smog and urban heat islands? Imagine a city near you: what would it be like to walk through it if it was filled with more trees?

Industry

When we learn about industry, it’s important to understand that there is an interdependent relationship among human actions, climate change, and the effects of climate change on humans. The environment that results from our industrial practices in turn affects our lifestyles and public health. We’ll be exploring this relationship with specific industries in the following sections, so keep this in mind as you read.

Economically speaking, industries are categorized into four sectors. For our purposes, we’ll be looking sector by sector at the involved industries and how they both contribute to and are impacted by the climate crisis.

Primary (raw materials)

The primary sector includes all industries involving the extraction and production of raw materials. The major industries in this sector are agriculture, forestry, mining, mineral extraction, and fishing, but we will only focus on a couple.

Mining: On land, we are constantly gathering land resources like wood and crops from the earth, but our activity underground has become just as environmentally harmful. Our extractive industries (oil, gas, mining) play a huge role in further polluting and depleting the earth of its rich minerals. Watch this video to learn about fracking:

Q: What is the fracking fluid’s role in collecting oil and natural gases? What is flow-back liquid and how can it be dealt with? Why is fracking so controversial?

With mining, we are literally reshaping the earth and unearthing large amounts of precious metals and sulfides. Iron and steel industries alone are responsible for 7% of world emissions because they burn coke, a carbonized form of coal, leading to more carbon emissions. Optionally, you can read about how LKAB, one of the world’s largest iron-ore companies, is moving to carbon neutral production.

• LKAB invests up to €39bn in massive transformation for carbon-free future, The Barents Observer article

When sulfide reacts with water and air, it becomes sulfuric acid, which seeps into nearby streams and groundwater. This process is called acid mine drainage and it’s the biggest source of water pollution from mining. Because acid mine drainage can be up to 300 times more acidic than acidic rain, it’s extremely toxic to humans and other vulnerable species. Read this article to learn about all of the different impacts that mining has on the environment.

• Environmental Impacts of Mining, WMAN article

Here are four videos that you can watch to learn more about the types of mining and each of their specific impacts on the environment. Pick two to watch and answer the next question.

Q: Explain the specific impacts on the environment of two types of mining that you learned about.

Over the years, numerous resistance movements have popped up to protest extractive activities. For example, since 2008, many people (climate scientists, environmental activists, indigenous communities, farmers, and business owners) have rallied for the Keystone XL pipeline protests. Watch this NowThis World video to learn about the controversy surrounding the Keystone XL (KXL) pipeline.

• Optional detailed article: What is the Keystone Pipeline?, NRDC article

Q: What are two ways that the KXL pipeline could worsen the environment? Why is the pipeline so controversial and what are your stances on the issue?

Although Obama rejected the pipeline’s border-crossing permit in 2015, Trump revived the proposal within weeks of his inauguration in 2017. As of July 2020, the proposal has been blocked by the Supreme Court, but there is still a huge debate centered around this proposal. We strongly recommend you stay updated on the status of the KXL pipeline proposal in the next couple of years!

Secondary (manufacturing and construction)

The secondary sector includes all industries involving the production of finished, usable products from the raw materials in the primary sector, usually for commercial purposes. Examples include metalwork, car manufacturing, petroleum refining, and hydroelectric power generation. Large-scale industries like these often require large factories and machinery, consuming enormous amounts of energy and producing waste materials that cause environmental harm. These are the biggest industrial contributors to the climate crisis, so you are probably familiar with many of them!

There is no doubt that since the Industrial Revolution, factories worldwide have been increasingly polluting the environment and harming surrounding wildlife through emissions and waste. In terms of emissions, manufacturing and electrical generating factories contribute more than 50% of greenhouse gases, mainly carbon dioxide, methane, and ozone (source).

Numerous industrial dump sites, filled with millions of tons of industrial waste, are scattered throughout the states; they may even be near where you live! The worst and most uncontrolled of these sites have been dubbed “Superfund sites” by legislation that was passed by Congress in 1980, and there are more than 1,300 Superfund sites around the US. Below are some aerial shots of several Superfund sites (source):

Q: What do you notice about the resulting land? How does the vegetation (or lack thereof) seem to be affected? What about the “water” sources (black and orange pools) in the photos?

With global warming, these dump sites are much more vulnerable to extreme weather events, which could potentially spread the toxins to nearby water sources and/or communities. Take a look at this map to find Superfund sites in your area, as well as sites around the country. You can also read this recent article about the state of these Superfund sites today.

• MAP: See the toxic sites near you that are threatened by climate change, NBC news map
• A growing toxic threat - made worse by climate change, NBC news article

Q: Where in the US do the sites seem to be most concentrated? Can you think of reasons why that area has the most Superfund sites?

It’s extremely important to note that the vast majority of Superfund sites are most likely to be located near low-income communities and communities of color. A recent 2020 study by the Shriver Center found that 70% of the country’s most contaminated sites are within one mile of federally assisted housing. These households (~77,000 families) are also disproportionately in low-income communities of color. Many of these families are unaware of the community health risks and/or don’t have the means to move out of the area. This kind of environmental injustice speaks to federal policies of allocating federal housing in contaminated areas. Take a look at this document from the EPA to see who exactly are being affected by Superfund sites.

• Population Surrounding 1,857 Superfund Remedial Sites, EPA document

Optional: Check out this video of the North Brooklyn Boat Club, an environmentalist group dedicated to cleaning up floating trash in Newtown Creek, a Superfund site on the National Priorities List. If you’re interested in doing similar trash cleanup efforts, then we encourage you to find one in your area!

• Newtown Creek: North Brooklyn Boat Club, On a Superfund Site, ToxicSites video

Industrial dump sites are the oldest and most basic method of waste management. Many US cities have some kind of developed waste management system, including waste treatment facilities, where sewage could potentially be repurposed into heat and electricity for the plant or renewable natural gas. Check out NYC’s waste treatment process if you’re interested!

• Wastewater Treatment Process, NYC gov. article

Apart from the environment, the next alarming concern with industrial waste is - you guessed it! - public health, especially with water pollution. The US has sufficient resources to build waste treatment plants, but countries like Armenia and the Philippines don’t have any systems for industrial waste management. Let’s look at Bangladesh, the most polluted country in the world, as a case study.

Although Bangladesh is a developing country, its major brick-making, clothing, and textile industries have worsened air and water quality to the point where millions die from respiratory illnesses and waterborne diseases. Watch this video to learn about how Bangladeshi children are especially affected by factories near them.

Q: How does the lead poisoning affect Anik? What were your personal reactions to the video?

In light of the climate crisis, many companies are implementing green factories, where workers use fewer natural resources and more renewable sources of energy, leading to reduced pollution and emissions. Fortunately, Bangladesh is in the lead of implementing this new kind of “green manufacturing.” The top three green factories - the first denim, garment, and knitwear factories of its kind - actually originated from Bangladesh, and it currently has the most green factories in the world.

• Optional: How Bangladesh can reap benefits from green factories, TextileToday article

So far, we’ve mainly talked about how factories affect climate change. Have you considered the reverse - how climate change affects factories? Most factory workers already work in tight spaces with no air conditioning or ventilation, which puts their health at risk on a daily basis. What happens as global temperatures rise and there are more hot days per year? These workers become even more at risk for heat exposure related conditions - heat stroke, fatigue, and even death. Outdoor workers like agriculture workers, commercial fishermen, and first responders are also at risk! As we keep learning about the climate crisis, it’s important to keep those who will be directly affected in mind.

Tertiary (service)

The tertiary sector includes all industries involving the provision of services like transportation and distribution of products. Examples include railroad, subways, and entertainment. This sector focuses on serving the customer rather than making physical goods.

Fast Food: With every burger, milkshake, and plate of fries comes a cost. The global fast food industry makes hundreds of billions annually and is dominated by “fast food giants.” These are your typical drive-by, chain restaurants: McDonald’s, KFC, Burger King, Pizza Hut, and so on. So just how big is their carbon footprint?

Take a look at this burger fact sheet about how much one hamburger affects the environment.

• Hamburger vs. Wildlife: The Environmental Cost of Beef, Take Extinction Off Your Plate article

Now take that one burger and scale it up to millions of burgers made daily in hundreds of thousands of chain restaurants around the world. Because the fast food industry and the climate crisis are both on such an enormous scale, it will take all of our efforts to make a substantial change. We should hold corporations like these fast food giants responsible for the amount of emissions and pollution they produce, and they should be progressing towards more environmentally conscious practices. This year, McDonald’s, the biggest burger chain, announced that they’re introducing “McPlant” - a plant-based line of burgers! They’ve also set a hard target for greenhouse gas emissions and have committed to a ~30% reduction in emissions. Although these are great improvements, we’ve still got a long way to go.

Entertainment: The entertainment industry, complete with Netflix shows and blockbuster films, plays a surprisingly bigger role in climate change than we’d normally think. According to a 2006 study by UCLA, the Hollywood film industry produces more air pollution in the Los Angeles region than the other five industries studied: aerospace manufacturing, apparel, hotels, and even semiconductor manufacturing. This means millions of metric tons of carbon dioxide annually!

Have you ever considered how big a Hollywood movie production’s carbon footprint is? Producing movies requires workers for special effects and set building and trucks for transporting equipment, not to mention the thousands of generators needed to power the set for cameras and lighting. While these diesel generators are emitting carbon monoxide in particulate matter, the power plant that’s providing electricity to the sets is also polluting the air. It’s also not just Hollywood - one hour of UK television can produce 13 tons of carbon dioxide, which is almost as much CO2 as an average American uses every year.

Some productions have actively harmed the environment with their extravagant scenes and props. Crew from Pirates of the Caribbean may have dumped chemical waste in waters around Australia, while a member of The Expendables damaged a protected bat habitat and others ruined beaches and parks for special effects.

Some movie franchises have taken the initiative to go greener, however. The Matrix Reloaded, the second movie in the Matrix series, recycled 97% of its set materials, including tons of concrete, steel, and lumber that were sent to Mexico and reused in housing for low-income families. You can read this article for more information about how Hollywood productions are reducing their carbon footprint.

• How Hollywood Is Reducing Its Carbon Footprint, Variety article

Hollywood is a host of major movie studios, each of which is its own corporation. Just like how we should hold fast food companies accountable for their role in the climate crisis, we should also speak up against the entertainment industry’s use of resources.

Tourism: The tourism industry is one of the fastest growing industries in the world. More and more luxury hotels, beach clubs, and amusement parks are popping up all over the world as people are travelling internationally. Although people usually just see tourism as a boost to the economy, it also accelerates pollution with careless littering and transportation emissions.

Think about it: traveling to our vacation destinations requires automobiles, airplanes, and trains, all modes of transportation that have the highest emissions. The noise pollution from constant arrivals of airplanes and other vehicles can disturb and change the natural patterns of the wildlife. Constructing resorts and luxury hotels not only devastates the natural environment but also generates much more sewage and wastewater. Food, energy, and water need to be extracted to offer the full “five star” experience to incoming tourists. And of course, the littering of beaches and natural parks results as millions of tourists pass through and leave their trash behind.

In 2018, the Philippines government had to close its most famous resort island, Boracay, to tourists for six months because the sewage had piled up to threatening amounts. CNN also reported that the majority of facilities on Boracay didn’t have proper sewage facilities, so the tourist island’s black sewage water flowed right into the crystal clear ocean waters.

Tourism and environmental awareness don’t have to be mutually exclusive! Many visitors these days participate in ecotourism, a form of tourism that involves travelling to exotic, fragile, and relatively untouched places to observe wildlife and build conservation awareness. Watch this video to learn about ecotourism in Indonesia!

Q: Compare the state of the coral reef environment before and after the ecotourists worked on conserving biodiversity.

Ecotourists get the best of both worlds - they can experience the thrill of travel while also being a part of conservation efforts. Even if you decide not to be an ecotourist, the motto “leave it better than you found it” should always be in the back of your mind. Whether you’re at the beach, a natural park, or an exotic rainforest, be sure to clean up after yourselves and do your best not to disturb the wildlife there!

Quaternary (information services)

Last but certainly not least, the quaternary sector includes all industries involving knowledge-based services. These include all kinds of media, research, blogging, designing, and more. In this digital age, the internet is so efficient that we don’t visualize the effect that our virtual activity has on the environment. But in reality, the “cloud” that we store data in impacts the environment more drastically than we think. The biggest effect: energy. Watch this video to get a grasp on the amount of energy that the Internet uses.

Q: What are data centers and how do they contribute to greenhouse gas emissions?

You’d think that sending an email or doing a quick Google search doesn’t have much of a carbon footprint, but when billions of people are sending dozens of emails daily and browsing websites, they add up. To give you an idea, a Harvard study found that two Google searches produce the same amount of carbon dioxide as boiling water on your stovetop. Even just slightly changing our internet habits, like sending thank you emails, would make a bigger impact than you think. Check out this article about ways you can change your internet habits to reduce their environmental impact!

• Optional: Why your internet habits are not as clean as you think, BBC article

Green infrastructure

Infrastructure like bridges, highways, and airports are impressive and have revolutionized the way we live and travel. Water management systems in particular, like city sewage and stormwater runoff networks, are responsible for giving us clean water and preventing environmental contamination. These systems are essential to a healthy lifestyle and environment, but are chronically overused and underfunded. Especially as extreme weather events and climate change related disasters occur more often, untreated stormwater runoff with toxins and trash is increasingly entering our water supply (sources like lakes and reservoirs that feed into nearby towns). In fact, 10 trillion gallons of untreated stormwater runoff, and sometimes literal raw sewage, are estimated to pollute our drinking water and environment every year.

In the water cycle, evapotranspiration is the process of transferring water from plants to the atmosphere through evaporation and transpiration. Infiltration is the process by which water is soaked into the soil.

Check out this simulation of stormwater runoff based on the land type. Adjust the precipitation levels and toggle among the Developed-High, Barren Land, and Forest options, looking at the numbers for evapotranspiration and infiltration.

• Runoff Simulation, Model My Watershed simulation

Q: In a few sentences, compare the amount of runoff that results based on the precipitation. Write a similar comparison of runoff based on the three land types that you were asked to toggle among. What is the most ideal scenario for minimized runoff?

Currently, certain areas in the US are increasingly experiencing higher contamination rates, respiratory illness related deaths, and wastewater overflows. Clean water is critical to our public health and environment and our current systems aren’t sufficient to address the problem. To upgrade these public wastewater systems would require hundreds of billions of dollars in investments - taxpayer dollars - per year.

In the 1980s, the concept of green infrastructure was proposed as a primary solution for stormwater runoff, but has expanded into a general way of solving urban and climatic challenges through the harnessing of nature.

Watch this TED talk, from 3:42 to 11:03, about green infrastructure for storm runoff and answer the following questions:

Q: What happens to the sewage in wet weather and why is this “combined sewer” so dangerous for us and the environment? Based on the speaker’s principles, define stormwater green infrastructure. Why should rooftops be the focus surface of green infrastructure? What is the purpose of plants in the sponge analogy?

Since the 1980s, we have come up with a wide variety of green infrastructure to better manage wastewater and we have implemented them into our daily lives. Projects include vegetated rooftops, rain gardens, bioretention areas, constructed wetlands, and porous pavement. To get an idea of the different types of green infrastructure, check out this catalog of green infrastructure projects in US cities and an article about different projects specifically in New York City.

• Green Infrastructure Examples for Stormwater Management in the Hudson Valley, New York Department of Environmental Conservation article
• Types of Green Infrastructure, NYC Environmental Protection article

Read about three different projects and answer the following set of questions for each project. Feel free to look for other project types via Google, but be sure to find credible sources and link them in your responses!

Q: Where is it mainly used? How does it work? What are the benefits? Who does it benefit?