CO2 contribution to global warming

Just a thought,

I work for a big car company, enjoying my job very much, and I work in a dept that helps out the CO2 targets and working towards reducing them in our products. Hence, I've been thinking about CO2 production as a net product concerning activity.

Some small cars such as a Ford Fiesta or Toyota IQ, are approaching nearly less than 100 grams per km of CO2 production. As humans breathe in air, use the O2, and produce more CO2, what do we contribute? I remember hearing the figure 190g/km for a runner (cyclists obviously go further for the same amount of effort so this would be reduced), but the increase over normal production (600 g per day not including exercise) will it not soon be more eco friendly to drive to the corner shop than run/walk/cycle there?

I appreciate other contributions to the worlds structure happen as an influence of cars, such as production, resource collection etc etc, but is it not an interesting thought that cars may actually be more eco friendly for a commute than under your own steam in the future?

Or does my 10 mile commute give me too much thinking time!?!?!?!

Let sensible debate ensue!

Methane is 21 times more powerful as a greenhouse gas than CO2, so if you fart on your way to the shop as well as run/bike/walk then the world will end. Apparently.

you realize there's a human in the car when you are driving 🙂

no idea about runners CO2 – my internet is running far too slow to research on google scholar, but taking CO2 out of the equation, there are all the other pollutants from cars to consider – NOX, CO, noise, vibration etc. then there are the social, economic and health problems associated with the combustion engine to consider…

i think it is PERFECTLY fair to say that a car is a far more damaging way to travel to work than walk/run/bike…

Methane is 21 times more powerful as a greenhouse gas than CO2,

Yes it is, however it doesn't stay in the atmosphere for anything like as long so it isn't actually worse than CO2, and your breath isn't releasing locked up Carbon, whereas petrol does.

Or does my 10 mile commute give me too much thinking time!?!?!?!

I'm going with yes. 😉

And that if that human farts whilst driving….

Well it doesn't bear thinking about does it.

The end is nigh. 😉

oh, and i'd be really surprised if a human body was less efficient than a combustion engine (which would therefore release more pollution) which will be pulling around a tonne of material around with it.

We don't really know what is causing the global weather probs-hell we have global cooling if planes don't fly…

But cleaner air is only a good thing!

Should we be wearing masks during out commutes?

Petrol engines are around 30% efficient, theres a lot of wastage in a human body though!

To confuse matters, cycling sometimes gives me wind!

I had considered the other pollutants that are caused by burning fossil fuels, but we create shit. Probably not quite as bad though.

I had realised about the human in the car, thats why I included the bit about 600g per day of rest, so 25g per hour ish, maybe 50 if you consider being asleep dramatically reduces that portion of CO2. So total for driving for an hour at 60kph would be 6000g/km plus 3000 g/km for human, so say ball park 10,000 grams CO2.

For a human to cover 60km, would take 2 hours on bike (again just fag paper estimation/calcs here) 2 hours of hard exercise producing 80 g/min would be about the same. I just dont know if it is 80g/min.

I've realised the solution though, if i cycle faster to work i'll have less time to come up with daft ideas,

Shit, that would raise my heartbeat/breathing and would produce even more CO2.

Plan C then

I realise right now that its still in favour of human power, but it could swing in the future, thats me point.

thought planes where making it cooler? pollution high in the atmos deflects the sun making it cooler.

Unfortunately, you, like most people, are not thinking about the total impact of a product, in this case, a car.

To produce a car requires the raw materials to be extracted or produced: rubber, steel, plastic, material for the seats, etc. This is energy intensive.

Then it is put together, again, requiring machines and tools and more energy. Then it is driven on roads, again requiring energy to build and maintain.

Then, there is the petrol, the production of the petrol, from extraction, refinement, shipment, distribution.

Then there is the final disposal of the car.

These are externalities. People aren't used to looking at a product with this holistic viewpoint, considering it's impact from cradle to cradle. A car that produced no CO2 while driving would still have far more environmental impact than a human walking to work. Electric cars, hybrids, these are all environmental dead ends, that assuage people's deep guilt, but still destroy the planet.

I've not even mentioned the social destruction of the automobile, because I've just had my dinner and it would make me feel sick. Cars are inherently un-ecological, and fudging about their CO2 emissions is just pathetic.

Ok

The short term carbon cycle (the turnover of Carbon through atmosphere and biosphere via respiration (breathing) and photosynthesis (plants using energy from sun to grow) This is what gives the earth it's natural greenhouse effect (about 32C) which pretty much makes earth a toasty warm +15c (on average) instead of the -18C it would be if it relied on just the suns direct heating effect.

The CO2 which is produced from fossil fuels is "extra" co2 – it is part of the long term CO2 cycle, using carbon which has leaked very slowly out of the short term cycle over hundreds of millions of years (by coal and oil formation from plants and animals). Burning a huge chunk of this long term carbon store over a (geologically- speaking) very small period of time circa 200 years or so is what the crux of the problem is at the moment, and the reason why CO2 is accumulating in the atmosphere at a faster rate than the short term CO2 cycle can remove it. Off course the long term carbon cycle will eventually remove it, via processes such as increase in the speed of the rock weathering cycle, but that will happen in a timescale that is of no relevance to us ie millions of years.

So problem is not how much CO2 a car produces compared with a human per mile, but the fact that a car is using up part of the earths long term carbon store at a very fast rate.

It's a bit disappointing that someone working in part of a motor manufacturers that deals with carbon targets has missed this fairly fundamental point.

gwaelod- good explanation.

Gwaelod – its nice of the car company to actually allow one of its employees to ride to work, though.

Motiforz didn't say he was the main policy maker. Maybe he makes the tea or is good with the spell checker?

20 years ago no car company cared a toss about CO2 – so surely this is progress?

I'm as eco as the next tree hugger – but cars are reaallly handy. Thats unlikely to change for generations – not with out ripping up huge amounts of infrastructure. Technology is a good thing, and sooner or later there will be such a massive energy revolution that we'll all wonder why we bothered posting on internet forums about the "state of the world". Fossil fuels will become redundant.

Build more wooden houses.

You're all missing the point that CO2 doesn't matter anyway, as it's all one big lie, and the very small temperature increases being recorded are all part of the natural cycle of warming and cooling.

Another point that people miss when trying to make this comparison, is that while a cyclist may be producing more (effectively recycled) CO2 when he's cycling, once he's at rest he produces a lot less CO2 because his body is far more efficient than the lazy biffers who drive in every day so overall it's a win.

I think gwaelod should be allowed to make a smug comment at the end of his post because it was so good.

Yeah, thats true. There's a really lazy biffer at my work who revs around the car park like a deaf grandma every morning and night. She'll keep getting bigger and bigger and make the car work harder and harder each day to get her to and from work.

Thing is that leaving aside the fossil fuels used in the production of our food the human body is carbon neutral.

Thing is that leaving aside the fossil fuels used in the production of our food

The problem is you can't because the carbon footprint of food (production and transportation) is significant.

Like gwaelog I can't understand how an engineer can miss the fact that CO2 released from burning fossil fuel containing carbon that was fixed from the air millions of years ago is different to the regular carbon cycle. What are they teaching in schools these days?

Though just to continue my last, for those saying how obvious it is that there's a difference, do you know exactly how much fossil fuel carbon is involved in delivering food carbon to your plate? What are they teaching in schools these days?

Aracer – no different to the fossil fuel burned going to the cinema, having bike bits delivered or to power your computer. The only important point is, are you adding carbon from outside the system or not. That's the issue with fossil fuels.

what gwaelod said.

Plants absorb CO2 to build sugars/starch, we eat sugars, we breathe out CO2, repeat(add a touch of sunlight as the energy source).

no net gain of CO2.

it's nice to know our future is in safe hands…

What a very interesting question. I look forward to seeing this idea presented as fact on climate denier websites and in motor manufacturer advertising campaigns globally very soon.

Aracer – are you just trying to be controversial? I find it hard to believe that you really think "it's all one big lie"

say 10km by bike takes 40min, and about 400 calories, 400 calories is about 100g of glucose, 100g of glucose is 0.57moles, which is converted to 3.42moles of CO2, weighing 150g.

So no the cyclist is in fact emiting 15g of CO2 per km.

also fatties need to eat more food to maintian their weight, so the fat biffer in the caris probably emmiting easily the extra 150g over the day, as well as the kilo he emits driving into work.

I'm still amazed by how the new Fiesta has ended up as heavy as an old Focus

Fiesta
kerbweight kg
1.1 1977 — 755
1.3i 1998 — 920
1.3 2002 — 1044
1.25 2005 –1101

Focus
1.4 2002 — 1150
1.4 2005 — 1229

This forum has a bit of a hostile climate to it!

I am only a placement student here, so don't worry, I don't quite have the power to kill us all yet.

I was asking for interesting and reasoned debate about it, and so far I've only recieved 1 or 2 substantial reasoned thoughts.

1) fit people use less CO2 normally
2) the actual co2 per km of a person (original post was a guess/rubbish memory)
any others sorry if i haven't mentioned a good thought

Ive also thought of
3) what if you use a bus – 30 people at rest with good mpg per person, vs a human during hard exercise.

I did mention in my original post if those who mentioned it would like to reread, that there is the production offset of CO2 and natural resource collection.

Nobody here uflly understands climate change, we are actually in a period of global cooling at the moment, even though CO2 levels are increasing, and of all the global warming and cooling cycles in the history of the planet, ice cores have shown the global temperatures rose before CO2 levels rose, which is an interesting point suggesting CO2 is an effect rather than cause.

However, we have neved seen such an addition of CO2 to the climate before, levels of production are much greater than at any time in history.

This forum has a bit of a hostile climate to it!

I am only a placement student here, so don't worry, I don't quite have the power to kill us all yet.

I posted quite late, sorry if it seemed a bit tetchy…

3) what if you use a bus – 30 people at rest with good mpg per person, vs a human during hard exercise.

But the bus is using fossil fuel, so it's adding to the total amount of carbon in circulation – the cyclist isn't.

What ooOOoo said, car have become much more heavy. For no obvious reason.

cars have become too fat and heavy i agree, although a weight gain has been in inevitable.

I have an 1998 vehicle, no abs, no known crumple zones, no air bags, no noticeable safety structure cells, hence i would be poorly protected in an accident.

New vehicles have to accomodate these features, which add considerable weight, even before you look at customer 'wants' such as powersteering (1998 vehicle doesn't have), heated screens, electric windows, electric seats, faster cars(bigger engines/charging air intake) etc

Some add weight some add size, but both contribute to emissions.

Manufacturers have just made the cars bigger to accomodate all this, which is why it has become confusing. The new KA is effectively filling the space left by the old Fiesta – small town car etc. Thats why theres a bit of confusion in the public (and industry!) about what a cars name means nowadays. Models tend to move out of their original market position.

The old golf was a small town car sporty hatchback type thing, now its a fully blown family car!

Good point, the car names are hiding things! A lot of people would say "I've always had a Fiesta, it's only a little car" But the definition of 'a Fiesta' has changed a lot.

I do remember one study that talked about bicycle MPG

If you ate locally produced organic bananas, your equivalent mpg was around 1200. But if those bananas had been shipped from 2-3000 mile away, it dropped to around 500 mpg.

And if you had eaten a highly refined, processed ceral that morning….your mpg could have dropped to around 45 😯

All because of the amount of fossil fuel used in agriculture.

Anyway a bit of wikippeediaing:

Cycling requires about half the energy of walking—around 12.0 MJ/100 km

Toyota Prius = 66mpg = 4.3l/100km
Energy content of gasoline = 32MJ/l

100km in a Prius requires- 4.3×32 = 137.6MJ/100km

So 100km in a car needs – 137 MJ
(& assume the driver requires 6MJ to sit on their ass)= 143MJ

and 100km on the bike needs – 12 MJ

So even assuming the cyclist eats twice as much as the car driver, there is a factor of over 10 between the two.

But what either driver ate could have made a big difference. If you ride a bike but all your food is produced using lots of oil from underground, then the CO2 produced to keep you alive could be quite considerable.

Nobody here uflly understands climate change, we are actually in a period of global cooling at the moment

Without wanting to sound hostile – you are wrong.

We are not in a period of global cooling. There is a general upward trend in global temperatures. However 1998 was a particularly hot year (the hottest on record due to cyclical El Nino effect) – an upward spike in the trend if you like, so the years since have not been quite as hot as 1998.

This does not mean that the TREND in global temperatures is downward.

Unfortunately many climate change deniers have pounced on this fact and repeat endlessly that the world is currently cooling. This slight of hand only works if you take 1998 as the starting point.

In fact, since 1998 we have had 8 of the 10 hottest years on record.

That's a really good explanation by Gwaelod. And aside from that, the "everything produces CO2" arguments show the folly of only looking at one aspect of a problem.

For cars to be able to make a positive difference to greenhouse gases, they'd have to have longer working lives, require less infrastructure, not affect people's behaviour in certain ways (2 hour commutes and the like) and people would have to find some way of keeping healthy without taking regular exercise…

All of this is hardly news though is it, I mean ultimately everyone knows how even the most Eco-friendly of cars is never going to have a Carbon footprint anywhere near as small as a bicycle…

Having said that, has anyone calculated the total carbon footprint for a bike? i.e. extraction and processing of material, assembly and shipping of components from multiple locations around the globe, Energy used in manufacture?

As green as the Bicycle is when compared to the modern car, it isn't the most Eco-friendly form of transport either, surely walking is going to win hands down in terms of minimum total impact…

if you look into global ocean temperature cycles, you will find that global sea temps are on a warming/cooling cycle of around 50 years.

Temps were rising in the 70s and 80s to mid 90s, and now they have started cooling again.

Don't get me wrong, I definitely understand the possibility and mechanism of global warming, and find it the most convincing argument currently about climate change, rather than some sceptics who base their opinion on no reason.

But NOBODY fully understands the full system, it is far too complex. If you wish to claim so, then I will have to disagree with you.

True walking (barefoot & naked) would use the least resources 🙂 but then again you can travel around twice as far on a bike than you could walking for the same energy.

A bike weighs around 15kg, a car weighs 100x more. So the difference in resource use there is massive.

The problem with the "nobody fully understands" argument is that it gives skeptics the opportunity to say "so why should we believe anything". I am not a scientist, but I choose to believe what every major scientific body that I've come across agrees on. Global warming is a real phenomenon and it is also man made.

Where does your information about ocean temperature cycles come from?

The National Oceanographic Data Centre in the US seems to disagree with you. Have a look at this paper:

ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat05.pdf

I was asking for interesting and reasoned debate about it, and so far I've only recieved 1 or 2 substantial reasoned thoughts.

1) fit people use less CO2 normally
2) the actual co2 per km of a person (original post was a guess/rubbish memory)

In which case you have (chosen?) to overlook the most important 👿

ie, that hydrocarbon fuels are releasing CO2 from geological formations, and cannot sensibly be compared to fuel / food derived from the biosphere.

I'd also like to see some credible articles on life cycle environmental costs for different fuel classes. Through taxation policy, our Government have made diesel far more popular – all on the (flawed?) basis of environmental benefit. These benefits are largely down to the higher mpg economy of diesel (ie lower CO2 per mile), but ignore PM10s, PM2.5s and SOx / NOx… and the fact that EU refinery capacity is geared to producing gasoline, not diesel – which has to be imported in bulk

here's a challenge for the skeptics out there;

it should be easy enough…

find us one – just one – peer reivewed paper that says something like;

'increased levels of atmospheric CO2 do not contribute to global climate change'

it has to be peer-reviewed mind…

just one.