Four Kinds of Pollution
Why Riding a Bike makes Green Sense
Being environmentally sensitive these days seems to to have come in vogue. If I had to look at myself as an example, I would say being “greener” was one of the reasons for taking up a bicycle, but probably not the single most important. But that’s OK. Putting aside for the moment any monetary savings and physical health improvements (very real issues to many of us), let’s take a moment and look at what the auto-centric society does to our environment in terms we can all relate to… pollution.
This is easily the first kind of pollution that comes to mind when examining the effects of the automobile on the environment. One of the biggest air pollution concerns is the large volume of greenhouse gasses emitted by automobiles. I found some statistical averages that estimate the CO2 (carbon dioxide, the most prevalent greenhouse gas) emission from a 20mpg automobile to be around 1.1 pounds per mile driven. This number is likely to be higher if you factor in that many of the first miles driven are when an engine is under-performing and creating more pollution, and that many of the trips taken by automobile are of a few miles or less. Another interesting statistic was that it takes a single tree 10 years to absorb the CO2 emissions from 90 minutes of freeway driving. I found these numbers impressive and sobering. But what does this have to do with riding a bike? Well …
Take a look at this graph :
Notice that walking and bike riding are the same (next to nothing in terms of CO2 output — essentially your exhaled breath). Yet we all know that for getting any distances, a bicycle will be able to accomplish this much easier. Why? Because the bicycle is one of the most efficient machines for translating mechanical energy into forward movement (the other? a sailboat using the wind). Your bicycle is the cleanest, most efficient way of transporting you to your destination.
The auto-centric infrastructure not only harms the environment by discouraging cleaner, more gentle forms of transportation, it allows pollutants from the automobiles to leach into our water supply. One EPA estimate is that for every 1 quart of (automobile) oil that ends up in our water can contaminate up to 1 million gallons of fresh water, and that 13.4% of used motor oil is dumped illegally and another 10.1% is land-filled. Then there are the soot particulates from both gasoline-powered and especially diesel-powered engines that end up on end up getting washed out of the air, onto the streets and then collected into our stormwater drainage systems which take them, not to the water purification plants, but into our lakes and reservoirs. There are all the other particulates — break pads, tires, rust, road salts, etc. that get washed into our water. Not very interested in taking a swim in your local lakes anymore, eh?
A Federal Highway Administration brochure states that a typical pickup truck going by at 50 mph is four times as loud as an air conditioner an eight times as loud as a refrigerator. The Organization for Economic Cooperation and Development (OECD) estimated in 1980 that 37 percent of the US population was exposed to “annoying” levels of highway noise (greater than 55 decibels), while 7% was exposed to levels that made conversation difficult (> 65 dB). I’m sure those numbers have gone up since the study was done in 1980. Just for your information, subjected to 45 decibels of noise, the average person cannot sleep and hearing damage begins at about 85 decibels. Apart from hearing loss, such noise can cause lack of sleep, irritability, heartburn, indigestion, ulcers, high blood pressure, and possibly heart disease.
OK, this one I kinda made up. Then again … maybe not. Do you get stressed when you find yourself behind the wheel, facing difficult driving conditions such as rude drivers, bad traffic, and racing to make deadlines all while having to answer that ringing cellphone? Keri has alluded to (in articles such as this) the fact that our auto-centric culture has taken away much of the civility and humanity that was once present. I think the automobile helps create an environment that de-sensitizes and de-humanizes the interactions that take place on the road. One of the things that, surprisingly, I found out about riding my bike is how much more interactive I am with everyone I encounter, and that includes people in cars. And the interactions, are, for the most part, friendly, enjoyable, and without rancor.
I don’t think we talk about the enjoyment aspects of riding a bike as much as we should. It seems to me we get caught up in talking about safety aspects, trying to convince the public that riding on the road with a bicycle is not fraught with peril. Not that safety isn’t important — it is. But more talk about the lessened stresses and enjoyment aspects of cycling might do better in getting new cyclists on the road.
So, in conclusion, I say to you, fellow cyclist, two thumbs up!! Pat yourself on the back every once in a while — you’re doing great things for not only yourself, but for the people around you, and for our environment. Keep up the good work!! Let’s see if we can convince the others to give up their cars for a couple of trips and use a bike (or walk) instead. It adds up. It can make a difference. It’s a great reason to keep on bikin’.