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  • CO2 contribution to global warming
  • Tim
    Free Member

    motivforz said:

    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),

    This may be completely true, but its also completely irrelevant when it comes to any discussion about Climate Change 🙂

    Human beings (or any enimal that breathes) dont release 'extra' CO2 through respiration – not what would be considered 'extra' in terms of climate change anyway

    Tim
    Free Member

    aracer – Member

    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.

    Please support this – i think its tosh 🙂 But i'd like to see your arguments

    Tim
    Free Member

    rkk01 – Member

    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

    I know that when it comes to the emisisons from housing, CO2 is used as a yardstick as it is difficult to fairly quantify the other emitted gases, and a reduction in CO2 will usually reduce otjher gases anyway – its all about reducing combustion.

    Although this is changing

    i can only assume that vehicles are the same

    porterclough
    Free Member

    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…

    This is a very good point – not only that, but all the people I know who commute long distances have switched to diesel. Arguably the extra mpg they get is just encouraging them to drive further – meanwhile people are dying of asthma because of diesel.

    Tim
    Free Member

    porterclough – Member

    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…

    This is a very good point – not only that, but all the people I know who commute long distances have switched to diesel. Arguably the extra mpg they get is just encouraging them to drive further – meanwhile people are dying of asthma because of diesel.

    good point

    juan
    Free Member

    So the difference in resource use there is massive.

    I shall had to that something.
    Bike are made of around 85% of metal (save the grip the shifter the cable outer and a few ring/seal that are made of plastic). Most of the car weight increase is due to plastic through the electric "needs" of modern cars.

    Plastic is a very heavy chemical industry (it's been years since I have done polymers chemsitry though) that reject loads of pollution and which raw material is:
    Oil.

    mjb
    Full Member

    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.

    Please support this – i think its tosh But i'd like to see your arguments

    Not saying they are right but there are a lot of scientists that believe this to be the case…

    http://www.petitionproject.org/review_article.php

    zaskar
    Free Member

    ooOOoo – Member
    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

    Could be the added options are heavy, also safety stuff like crash protection and impact beams weigh more as well as sound deadening.

    New Fiesta is a bigger car now.

    midgebait
    Free Member

    Nice one mjb, a submission by the Oregon Institute of Science and Medicine published in the Journal of American Physicians and Surgeons!

    I like the OISM page on Nuclear War Survival Skills…

    PMSL 🙂

    rightplacerighttime
    Free Member

    Motivforz, are you having a laugh?

    You come on here telling us that:

    Nobody here uflly understands climate change

    Then you happily assert that

    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.

    as if it was fact. Then when challenged over your source you come up with a news story on the BBC website that doesn't even say that anyway.

    What the article goes on to say (try reading to the end) is

    In addition, say Met Office scientists, temperatures have never increased in a straight line, and there will always be periods of slower warming, or even temporary cooling.
    What is crucial, they say, is the long-term trend in global temperatures. And that, according to the Met office data, is clearly up.

    Which is also what the paper I mentioned earlier says.

    If you genuinely are interested in learning anything about climate change, my advice would be don't take anything you read in the media for granted (even from the BBC) go to the original source of the data and check for yourself what was actually said by the scientists doing the work.

    rkk01
    Free Member

    re my questions regarding LCA of petrol vs diesel…

    I know that when it comes to the emisisons from housing, CO2 is used as a yardstick as it is difficult to fairly quantify the other emitted gases, and a reduction in CO2 will usually reduce otjher gases anyway – its all about reducing combustion.

    Although this is changing

    i can only assume that vehicles are the same

    … is not where I was going. At the point of combustion a diesel vehicle is more carbon efficient – but I am intrested to find out the relative benefits of diesel compared to petrol when the refining and transportation contributions are compared. I strongly suspect that the benefit of diesel become less apparent and are only justifiable in terms of HM Revenue extracting more £££ from consumers…

    mjb
    Full Member

    Nice one mjb, a submission by the Oregon Institute of Science and Medicine published in the Journal of American Physicians and Surgeons!

    As i said i don't necessarily agree with them but it is a peer reviewed paper as requested. There are people including 'scientists' who have different views to those that sell papers.

    Climate change is a massive subject that nobody fully understands which in turn means that all the arguments currently being put forward are likely to be incorrect in some way. It would therefore seem better to keep an open mind and at least understand alternative points of view rather than dismiss them without even reading them. I assume you can provide undeniable evidence that all their arguements are wrong?

    Tim
    Free Member

    mjb – Member

    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.

    Please support this – i think its tosh But i'd like to see your arguments

    Not saying they are right but there are a lot of scientists that believe this to be the case…

    http://www.petitionproject.org/review_article.php

    I have downloaded the document and will read it and comment

    in response though, and in the meantime:
    http://www.realclimate.org/index.php/archives/2007/10/oregon-institute-of-science-and-malarkey/
    &
    http://www.realclimate.org/wiki/index.php?title=RC_Wiki

    in return, these are very good links:

    The economics of climate change:
    http://www.climatechangeecon.net/index.php?option=com_content&task=view&id=20&Itemid=27

    History of climate change research:
    http://www.aip.org/history/climate/

    The late medieval warm period
    http://www.ncdc.noaa.gov/paleo/globalwarming/medieval.html

    What we learned in 2008:
    http://www.nature.com/climate/2009/0901/full/climate.2008.142.html

    Tim
    Free Member

    mjb – Member

    Nice one mjb, a submission by the Oregon Institute of Science and Medicine published in the Journal of American Physicians and Surgeons!

    As i said i don't necessarily agree with them but it is a peer reviewed paper as requested. There are people including 'scientists' who have different views to those that sell papers.

    Climate change is a massive subject that nobody fully understands which in turn means that all the arguments currently being put forward are likely to be incorrect in some way. It would therefore seem better to keep an open mind and at least understand alternative points of view rather than dismiss them without even reading them. I assume you can provide undeniable evidence that all their arguements are wrong?

    theres masses and masses (and masses and masses) of evidence, but a skeptic will still deny it on principle because (of course) its IMPOSSIBLE to be absolutely certain what will happen in 10-100 years time.

    What i dont understand is people not taking action anway. If the scientists are right, we hopefully wont feel the effects as badly, if they are wrong, we end up with a better world anyway – whats the harm in acting on it now? Unless your protecting your own interests that is…

    Energy Security and Climate Change are closely linked

    Tim
    Free Member

    Nice one mjb, a submission by the Oregon Institute of Science and Medicine published in the Journal of American Physicians and Surgeons!

    As i said i don't necessarily agree with them but it is a peer reviewed paper as requested. There are people including 'scientists' who have different views to those that sell papers.

    Is it peer reviewed though? http://en.wikipedia.org/wiki/Oregon_Petition (yes i know its a wiki)

    there seems to be some debate over its integrity

    ooOOoo
    Free Member

    We should cut all our emissions dratically for at least 2-300 years. Then see if we've improved things.

    That's fair isn't it?

    mjb
    Full Member

    there seems to be some debate over its integrity

    Yes there is and rightly so in many cases but a lot of the people conetesting it have no more experience than the authors.

    mjb
    Full Member

    when asked about her views on global warming, Palin's double Tina Fey responded, "I believe it's just God hugging us closer."

    Sounds the most likely reason to me.

    midgebait
    Free Member

    Amen!

    midgebait
    Free Member

    Somewhere I've got data on the external costs (i.e. those imposed on society in general e.g. air quality and climate impact) of diesel vs. petrol. If I recall correctly the external costs for diesel are lower in rural areas as the impact on air quality is low but the fuel and CO2 savings are a benefit. In urban areas the external costs of diesel are significantly higher than petrol, largely due to the health impact of fine particulates and other unpleasants in diesel emissions.

    I'm still pleased that I've found the page on nuclear survival skills though 😉

    ransos
    Free Member

    Getting back to the OP…

    Calculating the CO2 impact of running or cycling is quite tricky. We would need to know:

    a) Were any extra calories consumed, compared with doing nothing? (People who do nothing often consume excess calories).

    b) If extra calories were consumed, what was the food source?

    c) What was the CO2 arising from producing (e.g fertilisers), transporting and cooking the food?

    If we're considering cycling, we would need some information on the costs of producing and maintaining the bicycle.

    In order to make it a fair comparison, we would need to consider the full life-cycle impact of the car – e.g. raw materials, manufacture, servicing and disposal. Also the full life cycle of the fuel it consumes – extraction, refining, distribution and combustion.

    Now, I don't know the answer, but it seems highly unlikely that running or cycling is anything more than a tiny fraction of driving.

    gwaelod
    Free Member

    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

    None of this is relevant to global warming – the biosphere's (animal/plants) carbon budget is roughly in balance as photosynthesis is more or less equal to respiration. (Short term carbon cycle)

    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.

    I don't understand this bit – but it sounds as if you are claiming that you can add bits of the long term carbon storage reservoir to earths atmosphere and the earth won't notice it – you are wrong.

    Nobody here uflly understands climate change,

    Maybe some Met Office/Hadley Centre guys are mountain bikers 😉

    but even then we don't need to "fully understand" something before we make deductions based on the very large amounts of things we absolutely
    do know about it.

    we are actually in a period of global cooling at the moment, even though CO2 levels are increasing,

    It is difficult to describe just how massively utterly wrong this statement is. Assuming this a conclusion you have come to yourself it demonstrates that you are unable to read a simple graph. If you have just cut and pasted from some climate deniers website without any thought, then you should begin to wonder why they are lying to you.

    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.

    As you have already demonstrated a profound ignorance of the very basics of climate science such as short and long term carbon cycles, as well as shown your inability to interpret simple datasets in a meaningful way, it would be interesting to hear your explanation of events at the end of the last ice age. I wonder what you think the mechanisms behind onset and termination of ice ages are, and how carbon dioxide plays a role in the magnitude of the changes. (the term "Positive feedback" is a clue here)

    the fact that CO2 rises lag temperature increases in ice core records at ice age terminations should be no comfort to someone concerned with current temperature rises…quite the opposite in fact, although from your previous posts I doubt if you can explain why that is.

    Why not stop reading ridiculous junk science websites and do some simple basic science courses, then come back with your questions. The Open University intro to science courses are very good.

    if you are already a science graduate, then we are all ****.

    Tim
    Free Member

    the fact that CO2 rises lag temperature increases in ice core records at ice age terminations should be no comfort to someone concerned with current temperature rises…quite the opposite in fact…

    It is quite amusing that one of the most commonly used argument by skeptics is also one of the key worries of those who understand the science involved.

    Lag and lead is very relevant indeed – but we worry (a lot) about positive feedback loops!

    Yardley_Hastings
    Free Member

    currently wading through this http://www.withouthotair.com/ which is the best book i've read on climate change, well written, easy to read and all points raised seem to be substantiated with publications, ie not just a book of opinions.

    flicking through the chapter on transport, assuming the average UK car has a consupmption of 33mpg then that works out to around 80kWh per 100km driven, bikes come out at about 1kWh per 100 person km. interesting stat (page 118 if you're intersted)

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