Selling Walkability on Climate Change

The words climate change have the ability to trigger many different emotions and reactions in all sorts of people. Is it happening, is it not happening, is it man-made or is it all a hoax? Well, luckily this isn’t a post about the science of climate change. This post does, however, assume that climate change is happening and that although it might not all be “man-made”, humans are definitely speeding the warming of our only livable planet along faster than any other natural occurrence.

Our first presidential environmentalist, Thomas Jefferson, called cities “pestilential to the health, the morals and the liberties" of humans. If Jefferson had his way, every American would be a peacable farmer, living off the land and avoiding anything to do with large villages or cities. In fact, the environmentalist movement has historically been anti-city. When put in the context of Industrial Revolution, that thinking makes sense. Cities were the burgeoning hubs of manufacturing and squalor, belching smoke, ash and debris into the atmosphere while churning out products that advanced civilization, and where a cities’ workers lived in tenement row houses in terrible conditions (Read “The Jungle” by Upton Sinclair for an idea of life in Chicago’s stockyard neighborhood).

With more public awareness of the effects of climate change, cities have been put back into the cross-hairs. When carbon mapping first became popular, it seemed that cities were the main culprit of CO2 emissions because of the tendency to examine carbon emissions per square mile. Using this model, cities were red hot with emissions, while rural areas were cooler. However, if you flip that assumption around and examine carbon emissions per household, the carbon map starts to look different. Cities become places where it’s “cooler” and rural areas become “red hot”. Why is this?

Well, most carbon emissions today come from tail pipes, not manufacturing plants in cities, like they did in the Industrial Revolution. If you live in a city, you (hopefully) have more options to travel from place to place - public transit (trains and busses), scooters, bike or Chevro-legs. That means walking. If you’re living in a more rural or suburban area, then you probably don’t have a ton of options for getting places. Driving your car becomes the most convenient option and although it might seem better or easier, there are tons of hidden costs associated with driving even short distances. Car culture also plays a large role in the prevalence of driving. Watching the NCAA tournament recently, I was struck by how many damn commercials I saw for trucks. The best part of those commercials is that half the time they’re shown being driven, there’s nothing in the bed! What’s the point of having a truck if you’re not hauling a million pounds of “stuff” you might need everywhere? Pollutants are usually higher in rural and suburban areas precisely because cars are the most dominant form of transportation. Cities that are more walkable, and have more options for people to travel within the city, generally have lower pollutant levels.

Let’s take a look at a carbon footprint map for San Diego, using the carbon footprint map per household.

San Diego Carbon Footprint per Household.png


All the green areas around the bay and the coast are indicative of a low carbon footprint per household. Now, this doesn’t necessarily mean that San Diego has tons of different transit options, because the city doesn’t. It’s actually awful. But within those green areas, people don’t need to drive to accomplish various errands, they don’t need to drive to go to a restaurant, and they don’t need to drive to go to the gym. People feel comfortable walking or biking in their neighborhood, and they often prefer that to driving.

Now, let’s take a look at San Antonio’s carbon map, with carbon footprint per household.

San Antonio Carbon Footprint per Household.png

Interestingly, all the green there in the middle is San Antonio. So you can see that even in the heart of Texas, a city can be green. But look at the surrounding suburbs of San Antonio. DARK RED. This speaks to the lack of viable transit options, other than car, and the prevalence of sprawl in the surrounding area. There are miles of highway that surround the city and snake outwards towards cookie-cutter suburbs that have nothing but the same looking house for blocks and blocks. Want to ride your bike to the store, or to school? Good luck with that.

Now, San Antonio and San Diego are completely different cities. And every city in America needs to have their own specific way for dealing with an increasingly hotter climate. But expanding highways and designing cities around cars is not the answer. Knowing that vehicles are the lead emitter of CO2 should serve as a jumping off point for cities to start investing in their people. Make cities for citizens. Expanding walkability, bike-ability and public transit may be an expensive short term investment, but it’s an investment that will continue to return long term benefits for our Earth.