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Climate Impacts of Biking vs. Driving

keith.seas.harvard.edu

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Re: Climate Impacts of Biking vs. Driving

#41

Post by timthelion »

maxerickson wrote: post #40
timthelion wrote: post #38

Earlier quoted context omitted.

And steel actually produces even more CO2 to cast. Carbon steel, melting point 1500C vs aluminium, just 600C. http://www.engineeringtoolbox.com/melting-temperature-metals...

The specific heat is also important, not just temperature. You also have to look at refining (it takes a huge amount of energy to produce raw aluminum) and recycling (steel is really, really recyclable).

Well they both take more energy to cast than my average bowl of mashed potatoes and peas that's for sure!

Re: Climate Impacts of Biking vs. Driving

#42

Post by mikestew »

squidfood wrote: post #10

In my city, they've just taken some two lane roads down to one lane and eliminated car turning lanes, to add bike lanes. Those bike lanes see maybe 1 bike every 15 minutes, while the cars are now significantly more backed up (I've noted an extra 5-10 minutes of idling to travel a mile during busy times, no idea how many cars total in a day). Without denigrating the need for bike safety and separated lanes, I really w…

The implication seems to be that they took away a car lane to make a bike lane. It's entirely possible that the car lane was going away anyway, and they simply used the left-over space to make bike lanes.

So why did they take away the car lane, if not to make bike lanes? From what I've read, and observed here in Redmond, WA, is that the current fashion is to reduce four lane streets to three lanes (two directional, one center turn lane). The goal is to slow traffic in residential areas and...I forget what the other goals are. Anyway, it's a thing now. In your situation, perhaps they took away lanes to meet the current fashion, bike lanes just being the icing on that cake, or maybe they really did do it put bike lanes in.

Re: Climate Impacts of Biking vs. Driving

#43

Post by InitialLastName »

jogjayr wrote: post #33
gbrown wrote: post #6

Earlier quoted context omitted.

Not to mention whether exercise is substituted. What about a driver who runs on a treadmill, or does some equivalent amount of exercise without getting transportation in return? Plus, did I miss something, or was food not counted as a renewable resource? While agriculture is not carbon neutral, it's also not a 100% carbon source.

Not to mention that all the additional biking will improve people's health, thereby reducing the costs (and emissions) of healthcare and medication.

Last I heard, the jury was still out on costs of obesity care vs old age care. Anyone have an update?

Re: Climate Impacts of Biking vs. Driving

#44

Post by lyle_nel »

Emissions of CO2 on its own does not necessarily imply that there is a carbon footprint.

Besides the carbon footprint of transporting food, the food we consume is carbon neutral since the carbon in the food comes from the atmosphere. Therefore the CO2 gas we expel is mostly carbon neutral.

Cars are a different story since their carbon originates from ancient reserves(oil and coal) that has long since been removed from the carbon cycle. This carbon is now reintroduced to the carbon cycle, thus leading to a positive carbon footprint.

Put differently, if our food we eat consisted of carbon extracted from oil or coal, then we would be adding CO2 to the current carbon cycle, thus leading to a positive carbon footprint. However this is not true.

Re: Climate Impacts of Biking vs. Driving

#45

Post by wlesieutre »

lyle_nel wrote: post #44

Emissions of CO2 on its own does not necessarily imply that there is a carbon footprint. Besides the carbon footprint of transporting food, the food we consume is carbon neutral since the carbon in the food comes from the atmosphere. Therefore the CO2 gas we expel is mostly carbon neutral. Cars are a different story since their carbon originates from ancient reserves(oil and coal) that has long since been removed fro…

Oh but there's so much more energy in your food. There's the energy that went into producing fertilizer, energy to make pesticides, energy burned to run tractors, energy to process the harvest into what you get in the grocery store, potentially more energy involved in packaging. For plastic packaging, there's the oil used to make the carbon-rich polymers. Etc.

Just like cars, all of that energy comes from burning fossil fuels. The only way you'll find carbon neutral foods is if you walk out in the woods, pick it off a wild plant, and eat it right there.

Generally, the total energy that goes into producing and transporting something is called "embodied energy." It's not necessarily 1:1 related with carbon footprint since it can hypothetically come from renewable energy instead of fossil fuels, but it's a very related concept.

https://en.wikipedia.org/wiki/Embodied_energy

Re: Climate Impacts of Biking vs. Driving

#46

Post by InitialLastName »

sonthonax wrote: post #25
antisthenes wrote: post #23

As always, the practical, dirty, coal-using, environment neglecting China is way ahead in practice than the Boston PhD theorists funded by billions of old US money. This is a solved problem: you generate electricity via Solar and commute via electric bike, lowering kcal consumption and increasing average speed and range at the same time. The problems are cultural and infrastructural - it needs a critical mass of cycl…

Phone use while driving needs to be cracked down on though draconian measures like roadside flogging.

I'm almost convinced that if I see a driver looking at their phone while moving (the absolute lowest standard of "don't use your phone and drive"), I should be able to put my U-lock through their window. It's only fair to add to their cost enough to offset the extra risk they cause me.

Re: Climate Impacts of Biking vs. Driving

#47

Post by squidfood »

mikestew wrote: post #42
squidfood wrote: post #10

In my city, they've just taken some two lane roads down to one lane and eliminated car turning lanes, to add bike lanes. Those bike lanes see maybe 1 bike every 15 minutes, while the cars are now significantly more backed up (I've noted an extra 5-10 minutes of idling to travel a mile during busy times, no idea how many cars total in a day). Without denigrating the need for bike safety and separated lanes, I really w…

The implication seems to be that they took away a car lane to make a bike lane. It's entirely possible that the car lane was going away anyway, and they simply used the left-over space to make bike lanes. So why did they take away the car lane, if not to make bike lanes? From what I've read, and observed here in Redmond, WA, is that the current fashion is to reduce four lane streets to three lanes (two directional, o…

Here, they took a 3-lane two 2-lane+bike. Center wasn't turn lane, it was an alternating-direction in morning/evening. It was definitely part of a citywide "make bike lanes" initiative, if slowdowns were considered, that was the icing.

Re: Climate Impacts of Biking vs. Driving

#48

Post by jogjayr »

InitialLastName wrote: post #43
jogjayr wrote: post #33

Earlier quoted context omitted.

Not to mention that all the additional biking will improve people's health, thereby reducing the costs (and emissions) of healthcare and medication.

Last I heard, the jury was still out on costs of obesity care vs old age care. Anyone have an update?

There's an argument to be made that people who are healthier throughout their lives will be able to have a higher quality of life, and need less care, well into old age. So even if they live longer it might not cost as much in old age care. But you're right that that's more of a gut-feeling/heuristic kind of thing. We'd need actual numbers to know for sure.

Re: Climate Impacts of Biking vs. Driving

#49

Post by sonthonax »

InitialLastName wrote: post #46
sonthonax wrote: post #25

Earlier quoted context omitted.

Phone use while driving needs to be cracked down on though draconian measures like roadside flogging.

I'm almost convinced that if I see a driver looking at their phone while moving (the absolute lowest standard of "don't use your phone and drive"), I should be able to put my U-lock through their window. It's only fair to add to their cost enough to offset the extra risk they cause me.

If you enjoy occasionally bullying idiots who drive with their phones, do it. The police won't care, and there would not be enough evidence to prosecute you anyway if you obscure your face with.

The person in the car won't understand why you've done it, and will get all uppity and defensive, but will probably be jarred enough by the assault on his or her personal space to make stupid mistakes throughout the day.

Re: Climate Impacts of Biking vs. Driving

#50

Post by laughfactory »

Actually, recent research shows that a vegetarian diet has higher impact on the environment than eating meat. It's obvious too when you think about it. Consider how much lettuce you'd have to eat to replace the caloric content of one pound of beef. And there's a lot of resources which go into farming vegetables.

On the whole it's clear to me that of we could get the vast majority of commuting traffic to turn into cycling traffic, or non-traffic (get more people working remotely) then we'd vastly lower our environmental footprint and increase air quality. Plus we'd all get more exercise. But, of course, the automakers are hugely invested in keeping us buying new cars and driving them.

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