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29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

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Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#51

I truely hope a virus mutates the DNA of human sperm, or eggs; making the world population decline.

Most of the time I don't care about the de facto HN rule that only early adopters can downvote comments, but once in a while there's an occasion where it's really bloody annoying.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#52
post #42

Earlier quoted context omitted.

C02 per capita, China: 5.77 tons CO2 per capita, US: 17.28 tons Population, China: 1,334 million Population, US: 313 million Total CO2 emissions, China: 7.754 million tons Total CO2 emissions, US: 5.408 million tons (Source: Google queries). Note that this is CO2 emissions, where the article is discussion particulates. Given emissions controls (or lack thereof), China's going to be emitting far more particulate matte…

Who cares about CO2? (There is a serious obsession with CO2 in the world right now.) Pollution is the problem here. And it's a real bad problem. > And especially air travel. Huge contributor there. Sigh. OK, lets talk about CO2: http://www.travelmatters.org/calculator/individual/methodolo... Airplanes produce less CO2 per passenger mile than buses. And far less than cars. And if you do want to talk about CO2, how abo…

Who cares about CO2?

I do. Among other things.

Airplanes produce less CO2 per passenger mile than buses.

Airplanes are used to travel much further distances than buses. And by reducing the marginal cost of that travel, greatly increase the total amount traveled. So while a typical daily motor vehicle trip is on the order of 35 miles (based on average annual miles driven in the US), air flights are typically 10-100 times that (300-3000) or more. And with take-off and altitude gain, short-haul flights are relatively less efficient than long-haul. The per-trip CO2 emissions are thus vastly higher -- you're dividing by 2-4, but multiplying by 10-100.

Additionally, many of the modes listed on your reference can substitute electricity (which can be generated from non-fossil sources). Heavier-than-air travel pretty much doesn't exist without fossil fuels: liquid hydrocarbons are simply too dense, cheap, and versatile a fuel and energy carrier. The maths on biofuels simply don't work out, except at very low fractions of existing fossil fuel use. Substituting 10% of present oil consumption biofuels might be possible), but with an effective cost of $600/barrel or more, and that 10% would have to supply portable, emergency, and defense, as well as commercial aviation needs. I see lighter-than-air craft as more viable in a not too distant future.

And if you do want to talk about CO2, how about CO2 per GDP?

That works out roughly to the amount of fossil fuels used per unit GDP, though it varies based on fuel source (which I don't factor in). I used Wolfram-Alpha to look up GDP per quadrillion BTUs a couple months back:

For China & India, it's about $60b/quad.

http://www.wolframalpha.com/input/?i=china+GDP+%2F+%28total+...

http://www.wolframalpha.com/input/?i=india+GDP+%2F+%28total+...

And for comparison, the United States -- we use far more energy, but use it far more efficiently as well at $150b/quad: http://www.wolframalpha.com/input/?i=United+States++GDP+%2F+... But nothing like the Swiss at just a hair under $400b/quad: http://www.wolframalpha.com/input/?i=Switzerland+GDP+%2F+%28...

Italy shows in at ~$275b, Germany ~200 (plot's a bit wonky), UK ~$250b/quad, Spain ~$240b/quad, Japan ~$250b/quad, Russia ~$40b/quad.

Incidentally, growth in GDP and energy use for China & India:

http://www.wolframalpha.com/input/?i=china+total+primary+ene...

http://www.wolframalpha.com/input/?i=india+total+primary+ene...

After all we can't keep the entire world in poverty in order to reduce CO2.

I see no real choice in the matter. GDP's going to get tanked one way or othe other (climate change, peak oil, peak everything). We're on an unsustainable path. Not cutting carbon emissions is going to be rather markedly worse than cutting them, in the long run (though next quarter's profits will take a hit in the latter case but not former). And we're going to have to learn to get by on vastly fewer fossil fuels as well.

As I've said elsewhere, the only reason China has low numbers is because of the human misery of their poor population.

Given their present energy mix, yes. However if they were to pursue renewables to a maximum extent, you might be proven wrong (I've got some doubts on the feasibility of this as well, but given other alternatives, it's really the only option we've got).

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#53
post #48
post #46

Earlier quoted context omitted.

If both of those were correct, it would cost more to cycle 10 miles every day than it would cost to drive 10 miles every day. It doesn't, therefore your points are wrong.

Except it does actually cost more to cycle. You just don't notice because when you buy food it doesn't have a label saying where you used those calories. It does depend on what you choose to eat though. If you eat beans vs burgers. The cheap food comes close enough to driving to not matter, but most people eat nicer food and then it's more expensive to bicycle.

No it doesn't I used to cycle over 16 miles day and I did not eat any more food - I just lost weight which made me healthier.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#54
post #14
post #4

Earlier quoted context omitted.

The low hanging fruit is always getting others doing something. I for myself see the low hanging fruits with the things I can do or influence.

Honestly there isn't much you can do. Most pollution is industrial, and most industrial pollution is not in the US. Recycling just causes more pollution, so that doesn't help. You can turn lights off and install CFL's, but the difference is tiny. Riding a bike vs driving actually causes more pollution (because farms make lots of pollution) [unless you replace exercise you anyway do with bike riding]. Coal burning in…

According to this calculator http://bicycleuniverse.info/transpo/energy.html

A 155 lb. cyclist gets about 75mpg equivalent, factoring in a typical diet. The vegan gets 145mpg. The site also claims that even with an all-beef diet, cycling is more efficient than driving.

A physics professor (http://physics.ucsd.edu/do-the-math/2011/11/mpg-of-a-human/) gets similar results: factoring in the carbon footprint of extra food consumed, biking comes in at roughly 70–130 MPG.

Even these analyses don't seem to include the embodied energy it takes to manufacture a car, which is huge and should be considered a tax on every mile driven. Bicycle manufacturing is obviously much less energy-intensive.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#55
post #40

Earlier quoted context omitted.

What kind of silly propaganda made you read where biking causes more pollution than driving?! btw, if you look at CO2 emission and greenhouse gas emission, you'll find that USA and CHINA are pretty much tete a tete: http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dio... http://en.wikipedia.org/wiki/List_of_countries_by_greenhouse... Obviously, emission pro-capita is quite different. So, yes, the low hanging…

> What kind of silly propaganda made you read where biking causes more pollution than driving? Do the math. It's quite clear. You don't realize just how much fuel (diesel) farms use to grow that food, and then your body is not as efficient at converting the food into motion. It's a double whammy and you end up with cars being more efficient than bicycles. > Obviously, emission pro-capita is quite different. Yes. Obvi…

I commute 30km a day, consuming around 600 kcalories (it's about (0.1 calories per kg per minute for a 70kg adult going 25kmh). Driving would cost me about 21000 kcal (0.7 gallons a day, that is 0.7 * 31000 kcal in a gallon of diesel). So my car is about 36 times less efficient than me.

Do yourself a favour and stop watching fox news.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#56
post #48
post #46

Earlier quoted context omitted.

If both of those were correct, it would cost more to cycle 10 miles every day than it would cost to drive 10 miles every day. It doesn't, therefore your points are wrong.

Except it does actually cost more to cycle. You just don't notice because when you buy food it doesn't have a label saying where you used those calories. It does depend on what you choose to eat though. If you eat beans vs burgers. The cheap food comes close enough to driving to not matter, but most people eat nicer food and then it's more expensive to bicycle.

I'm sorry, but this is crazy science.

Looking at kilojoules and efficiency of energy, a bicycle is much more efficient on the order of hundreds, just looking at mechanical resistance and the energy needed to get the vehicle moving.

Also, while competitive/fast cycling requires large amounts of food to sustain, the extra fuel needed to commute by bike doesn't require much more than an extra handful of almonds or in my case, an extra beer in the evening.

The human body gets more efficient at a given exercise over time –– that's why calories-in/calories-out is never an equal proposition in a trained athlete (and regular bike commuting is in some ways "training.")

If you break it down into prices, bike commuting might cost an extra $1-$2 in food per day. OK, fine. However, that mitigates the $3-4 in fuel cost for mileage over a 20 mile commute. Maintenance costs on a bike are negligible compared to a car: $100 in chains, cassettes and brake pads annually vs. the $1,000-2,000 in usual car maintenance costs per year (PLUS, repairs).

As for environmental costs: yes a bike requires carbon to build and transport across the Pacific. But the heavy huffing-and-puffing C02 contributions of a cyclist is negligible to that of a car.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#57
post #39

Earlier quoted context omitted.

"Riding a bike vs driving actually causes more pollution (because farms make lots of pollution) [unless you replace exercise you anyway do with bike riding]." That is totally nonsense. You simply invented that nonsense. Let's put some numbers in : My bike weights 15kg, my body 85. So I move around 100kg with my bike. My small Toyota weights naked 1500kg, so I am moving 1700kg around(including my weight and gas or fue…

Lots of numbers and you ignored the only two important ones because it doesn't fit with your preconceived notion. 1: The efficiency of converting that energy into motion. A car is MUCH MUCH more efficient than a person. 2: The amount of energy from diesel needed to grow those food calories in the first place. Again, a car comes out way way ahead. > Farms don't make lots of pollution, and their pollution is natural, M…

Lets look at a model. You are making the claim, so you provide the cited numbers to fill it in.

To begin with - lets assume all joules are equally polluting. This isn't true, but we'll get to that.

Jp = the number of joules needed to move a person a distance.

Je = the number of joules needed to deliver Jp to the point of use.

Jt = the total number of joules for a mode of transport

Simply:

Jt = Jp + Je

Therefore a first approximation is to compare Jt(bike) with Jt(car)

However there are other factors that must be accounted for in this equation:

Jm - the total number of joules needed to manufacture the transport (full supply chain), and deliver it to first point of use.

Jl - the number of joules needed by a person anyway - farming can't just be eliminated, people require food to remain people. (Jl stands for joule's life)

Jl' - the number of joules needed to transport the minimal "keep people living" joules to point of use.

It should be noted, that Je and Jl' are related in the bike case, so Je in the bike case will only be the extra energy required to deliver additional food, not the energy required if the Je for a bike were delivered in an entirely separate manner. With Je for a car - the energy source, energy delivery etc are an entirely different infrastructure.

So factoring those in we get:

Jt = Jp + Je + Jm + Jl + Jl'

Of course - at the beginning I mentioned not all joules are created equal. So we need some sort of pollution index. I don't know a simple polution index formula, but assuming it exists, we will call it P. The output will be a normalized value that can be simply added to understand total polution. So:

P(Jt)= P(Jp) + P(Je) + P(Jm) + P(Jl) + P(Jl')

I want to note about the pollution function - the pollution of P(Jp) is essentially 0 in the bike case, because it is just metabolism. P(Jl) will most always be close 0, because it is metabolism again. The polution from delivery is captured in other variables.

This model could be further refined into pollution per travelled km, rather than the pollution per joule used. It could be better refined by including the Jm costs as an amortization of efficiency over the total number of travelled km. Etc. But for now, the model as stands is a good way of determining the claims first order validity.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#58
post #35

Earlier quoted context omitted.

When I lived in China in 2002, we had more than a few dust storms where the sky would turn completely yellow...it is a bizarre surreal experience. On my recent tour of duty starting in late 2007, I only experienced one dust storm in the spring of 2008, then nothing. I haven't seen one for a very long time, but it could be that they've just solved the problem for Beijing (doubtful, since we are right smack next to Inn…

> This is like the only thing...the only thing...that has gotten better in China while I've been here! Slightly off topic, but what are the things that have gotten much worse?

Traffic, pollution, Internet censorship and VPN attacks, rent, visa rules, taxes.

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#59

I truely hope a virus mutates the DNA of human sperm, or eggs; making the world population decline.

I'm getting a serious Poe's law vibe from this comment and username.

Benderism: save the world by killing all humans.

http://humanities.philosophy.objectivism.narkive.com/SivGxJB...

Re: 29% of Bay Area's particulate air pollution comes from across the Pacific (2010)

#60
post #40

Earlier quoted context omitted.

What kind of silly propaganda made you read where biking causes more pollution than driving?! btw, if you look at CO2 emission and greenhouse gas emission, you'll find that USA and CHINA are pretty much tete a tete: http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dio... http://en.wikipedia.org/wiki/List_of_countries_by_greenhouse... Obviously, emission pro-capita is quite different. So, yes, the low hanging…

> What kind of silly propaganda made you read where biking causes more pollution than driving? Do the math. It's quite clear. You don't realize just how much fuel (diesel) farms use to grow that food, and then your body is not as efficient at converting the food into motion. It's a double whammy and you end up with cars being more efficient than bicycles. > Obviously, emission pro-capita is quite different. Yes. Obvi…

@ars: You're not doing the math. You're just repeating the same claim, which seems wrong, and probably is wrong. You should certainly not be surprised that you're not convincing anyone. And saying "It's quite clear" is really rich, because, of course, it is not clear at all.

I think the best rebuttal has to do with the cost. The cost of buying, fueling, and maintaining a car is much greater than that of a bicycle plus the incremental food cost for the rider.

Additionally, @wes-exp has pointed to figures (just concerning MPG equivalent, not counting buying and maintaining) that have bicycles much more efficient than cars.

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