Be Green: Drive

When it comes to saving the environment, things are often not as simple as they seem at first blush.

Take, for instance, the debate about paper bags vs. plastic bags. For a number of years, anyone who opted for plastic bags at the grocery store risked the scorn of environmentalists. Now, it seems that the consensus has swung the other direction — once a more careful cost accounting is done.

The same sort of uncertainty hangs over the choice of disposable diapers vs. cloth diapers.

At least some choices are beyond reproach environmentally. It is clearly better for the environment to walk to the corner store rather than to drive there. Right?

Now even this seemingly obvious conclusion is being called into question by Chris Goodall via John Tierney’s blog. And Chris Goodall is no right-wing nut; he is an environmentalist and author of the book How to Live a Low-Carbon Life.

Tierney writes:

If you walk 1.5 miles, Mr. Goodall calculates, and replace those calories by drinking about a cup of milk, the greenhouse emissions connected with that milk (like methane from the dairy farm and carbon dioxide from the delivery truck) are just about equal to the emissions from a typical car making the same trip. And if there were two of you making the trip, then the car would definitely be the more planet-friendly way to go.

Phil Steinmeyer

And if you hike 15 miles to the store, it's much WORSE!

I guess an all-milk diet, supported by frequent walks to a distant store is not very environmentally friendly. I'll keep that in mind...


Someone had better tell the UK government about the plastic bag thing... a proposal to ban supermarkets giving out free plastic bags if no voluntary curb made it into last week's budget statement.

I'm not convinced personally - follow up on Ireland's plastic bag ban (introduced solely to combat litter) showed more sales of bin and nappy (diaper) bags, with more truck journeys to deliver them.

Oh - and on the Hummer/Prius thing - the 'Green Lantern' guy on slate has run the math...


Even assuming all his math is right, the use of milk is the most deceptive part of this story.

"Cattle are `responsible for 18% of greenhouse gases, more than cars, planes and all other forms of transport put together.' This includes the fuel burned making fertilizer, to produce the meat and transport it, as well as the obvious cow fart and manure production of methane, 20 times more effective as a global warmer as CO2"


Everyone's rehashing the same old tired line that you could walk to the grocery store and not change your current consumption habits. No, you can't. At some level, eating is a simple matter of counting calories. If you take in more than you burn, you gain weight, and vice versa. Eventually you will get hungry and eat more. It might not be the cup of milk that day; it could be an extra snack 3 days from then.

Where Goodall is wrong is that the emissions from the car are not the only pollution. If he is counting milk delivery, then what about the emissions from the refinery, and the cost of transporting the gasoline to gas stations?


You should drive to the store and drink a carton of milk. It could be the end of civilization as we know it if you don't.

If everyone was to give up dairy and walk everywhere the dairy and automobile industries would be devastated. Thousands of jobs would be lost. The economy will plummet because the production and consumption of goods is viewed as anti-green.

Countries in poor economic states generally have little interest in the health of the environment. Why should they care about the future of the world when its citizens are starving now? Then you're back where you started, a developing country willing to sacrifice the environment to return to the time when most people weren't living in poverty.

To avoid this we should consume as much as possible in hope that a good economic state will encourage innovation and technology that will solve the problems we create in the environment. I do not want to suggest that we should be wasteful but obnoxious conservation can be as dangerous if not more dangerous than drinking milk while driving.



Rice is also a major methane producer.


So ride your bike, burn less calories and drink less milk. Or better yet, skate your way to the store, kickflip back lip that 8 stair on the way.

Walking means lower health costs, so walking is definitely the way to go.


This is so stupid, it drew me into my first comment on the blog. Not everything can be a carbon calculation. How about the good you do your physical health walking to the store? How about the good you do the community taking one more car off the road, making it that much easier for everyone else who actually needs to drive to get where they're going and find a place to park?


As a competitive triathlete, I'm hyper aware of how many calories I use. With 6% body fat, I need to replenish everything I burn. Being somewhat compulsive, I've done the math on costs of driving vs. cycling vs. running.

Per mile traveled, it costs A LOT more to put fuel in my body than fuel in my car (which gets 27 mpg). Amortize in equipment (car, bike, shoes, etc.) and add maintenance (oil, tires, worn bike parts, etc.), and driving is still a bit cheaper.

Consider my short term health gains from being physically active...cycling and running win. Consider the long term possibility of a major cycling accident (much higher likelihood than an injury-producing car accident) or blowing out a joint running...who knows?

I know this isn't a direct relationship to carbon, but it's another instance that's counter-intuitive (and much more closely tied to economics).


Jeez. The human race spent millenia learning agriculture, domesticating animals, reducing manual labor (all of which made possible art and literature and government and trade) and the Carbon Footprint Mafia (forever after the "CFM") would have us all go back to walking through the forest, eating whatever leaves and shoots we can find and hiding from the occasional sabertooth tiger.


When the argument begins to call into question whether or not driving is more green than walking, then the whole concept is ludicrous. I'm buying a Hummer tomorrow.

Kristin Amdahl Marino

I don't like milk. Furthermore, I feel better after taking a walk and am less inclined to consume anything. If I drove that short distance it's probably because I am too lazy to walk. If I am too lazy to walk, I probably am not taking optimal care of myself. If I am not taking optimal care of myself I probably feel kinda crappy. If I feel kinda crappy I might consume more (which of course requires there be products available for consumption, which require energy to produce)to try to make me feel a little better. Either way, I wouldn't drink that glass of milk.


Sounds to me like the milk vs. driving comparison was borrowed directly from here:

Bill Jefferys

The calculation ignores the fact that one uses nearly as many calories while driving as while walking, due to your basal metabolism which cannot go below a certain lower limit. Heck, just lying around on the couch doing nothing you'll use up calories at a rate that isn't that much lower than when walking to the store.

Do Ma

what a crock. we can eat/drink whatever we want, which we would likely do anyway regardless of mode of transport.

In fact, if I drove and you walked the same trip, I would be back in time to crack open a couple of beers, and then set to work to really destroy the planet.


This seems like a poor parable to communicate an obviously true point. Every "carbon footprint" calculation is a ludicrous fiction, and the reductio ad absurdum for reducing one's climate impact is suicide.

Living green is about lying to yourself to raise self-esteem in a guilt-driven value system.


The point of the analysis is that the conclusions we reach are based on what we choose to include in the analysis and the assumptions we make. Several comments have addressed alternative scenarios and assumptions that could have been made. The multitude of possibilities creates the complexity that makes accurate calculations impossible.

The underlying hypothesis here is that walking rather than driving short distances is better for the environment. But when our choice not to drive is replaced by the decision to walk, there are other consequences to the environment.

We must also consider that environmental impact is not our only concern. How do you value the additional time it takes to walk? How do you calculate the health benefits? What about the net impact on the economy as a whole (auto sales down, shoe sales up, medical bills, car repairs, etc.)? There are numerous other factors beyond environmental impact that weigh on our decision making.

This analysis just illustrates that the truth behind simplistic assertions (walking is better than driving) often depends on our analytical choices and hidden assumptions about the consequences of alternative decisions.



good environmentalist dont eat/drink cow products for just that very reason. I'd like to see the analysis done with silk and generally compared to an vegan diet.


Could be worse... What if you're lactose intolerant?

Punditus Maximus

Why assume that the person walking to the corner store isn't eventually going to end up with one fewer car? That would make up for pretty much anything.

And, yes, of course folks aren't going to change their eating habits much, so the whole discussion is more than a little silly.