By Jasmine Kerber '20
Transportation accounts for more than a quarter of greenhouse gas emissions in the U.S., but only 14% of worldwide emissions (IPCC 2014). Of course, a higher percentage of people can afford cars in the United States than in many other countries. Much of our nation is also organized in a way that makes driving convenient—some of us couldn’t reach school, work, or the grocery store without owning a car. As a result, we’ll need to form new habits, improve infrastructure, and encourage social change to make our transportation greener. Still, I hope a culture that encourages more sustainable transport will grow in the coming decades.
Public and Electric Transportation
Which emits more greenhouse gases, a city bus or a single car? That’s sort of a trick question—the bus emits more pollution per mile it drives, but if 20 people ride the bus, each of their carbon footprints are far lower than if they’d all driven their own cars. In other words, all forms of public transportation are more environmentally friendly than taking the same trip alone in your vehicle. Even carpooling with a few friends is a better (and usually cheaper) option than riding alone. Still, some forms of transit have lower emissions than others.
Many cities are working on low-emission public transit. Several nations in Europe and Asia have been building high-speed electric train lines since the 1980s. These trains can significantly reduce oil consumption, especially because they’re an alternative to both cars and planes. Electric cars also promise zero emissions on the road—a truly revolutionary concept. They could become a particularly important green transport option in rural areas, where public transportation and bike riding are not often practical. Unfortunately, the $100,000+ price tag on a Tesla isn’t affordable for the average American. The $30,000 Nissan LEAF is more affordable, however, so we definitely may see more electric car options coming to the market soon.
One other factor to keep in mind regarding electric vehicles is their energy source. In other words, a car that emits no greenhouse gases on the road might still create some negative environmental impact if charged with non-renewable energy. The more renewable our energy mix becomes, the greener electric vehicle use gets.
Cities can encourage greener transportation by making it more convenient. Copenhagen provides one fascinating success story in this category. Copenhagen’s bike culture began evolving in response to the 1970s oil crisis. Without a steady supply of Middle Eastern gas, residents needed other transportation options. By the 1980s, the city began separating bicycle and car lanes, and has continued to expand and refine the system ever since. Today, over 200 miles of bike paths around Copenhagen allow people to cycle most places, plus trains include special carriages for bike storage, and taxis are required to have bike racks. The result? More than 30% of trips made around Copenhagen now occur by bicycle.
Bogota, Colombia also focused on convenience to encourage public transit. Their Bus Rapid Transit (BRT) system separates public bus lanes from the rest of the street so that buses wouldn’t get stuck in traffic. The speed factor has made the program very popular—BRT transports tens of thousands of people every hour.
In general, when nice public spaces become available, people use them. Safe sidewalks promote walking, bike trails encourage biking, and reliable, convenient public transit grows busy. Infrastructure is certainly an investment that cities can’t all afford right away, but history goes to show that it’s a good investment when it makes healthy and environmentally friendly habits easy.
So you rode your bike to the grocery store. But did your groceries take a long drive to reach you? Whenever possible, buy local! Every day, freight travels thousands of miles in trucks, trains, and planes that each produce pollution. Local shopping decreases your carbon footprint. It also stimulates the local economy and supports jobs in your area, so it’s a win-win! Of course, you probably don’t have all the ingredients you need for dinner growing in your 21st century backyard, but the idea is to buy local when you can. Also remember that doing so increases demand for the things your community produces. Finally, it’s a good idea to check if anything you purchase is sustainably sourced, but that’s a topic for another blog…
In summary: Walk or bike if you can, and if not, try to use public transportation. Make more of your purchases local. Show demand for those affordable, fully emissions-free electric vehicles! And ask your local government to add sustainable transport options.
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This is a forum for students to share their writing on intersectional environmental topics, curated by Students for a Sustainable Stanford. Writers of all backgrounds, abilities, and perspectives are welcome.