Which produces more carbon dioxide of these two.......?

Question

..the average family compact car doing average annual mileage OR the average family (2 adults + 2 children) just breathing for a year? (We can leave digestive gases out of the equations!) I have seen a calculation showing that they produce about the same...2.5 tonnes. Is this right? (..and pretty scary when you look at the impact of global population growth, irrespective of what we do to reduce industrial emissions!) Thanks for you replies.

General concensus is that it is the car that produces more. I was kind of hoping that someone could walk me through the maths, you know average amount of oxygen per breath or grammes/minute or whatever, molecular weights, Avagardos Numbers and all that good stuff that has fallen out of my head through neglect.

Anecdotal reports say that the Average Human exhales 1kg of CO2 per day, (working out not shown and sounds conveniently rounded to me!) depending on weigh, age, exercise and such. So

4 x 365 x 1kg = 1.460 tonnes of CO2/family/yr.

The point that I did not understand before is that the size of the population does not matter. ALL CO2 that we exhale has come straight from the atmosphere, from the carbon we eat. Again this is ALL fixed by photosynthesis of atmospheric CO2 and comes either directly from the plants or via the animals that ate the plant prior to us consuming them. An expanding population only eats, hence exhales CO2 within this closed cycle.

Answer 1

Please do the research and tell us. Look for 'carbon footprint'.