Based on the following figures….we’re all doomed!
Average human vital capacity (not volume) is I am informed, around 5.8 litres. Lets say the average adult human breathes at rest 16 per minute at around 0.5 litres per breath (Tidal volume) multiplied by the approximate world population of 6.6 billion (And counting) multiplied by 60 minutes in an hour, and twenty four hours in a day; multiplied by 365 days in a year. So; over a year, 6.6 billion people take on average 8,409,600 breaths each, which makes approximately 27,751,680,000,000,000 litres of air exhaled (I think). This is just a simplification you understand based on the premise that an adults expiration rate works out the same volume as a child or juvenile, whose respiration rates are much faster and vital capacities smaller.
According to reputable sources around 4% of human exhalation on average is CO2. This means we as a species exhale (On Average) 1,110,067,200,000,000 litres of CO2 per year directly attributable to a single human activity, to wit; breathing.
1,110,067,200,000,000 litres divided by 1000 gives us 1,110,067,200,000 cubic metres. Each cubic litre (1000 litres) of gaseous carbon dioxide at atmospheric pressure weighs around 1.98kg. Two thirds of which is oxygen and one third carbon. So multiply 1,110,067,200,000 cubic metres by 1.98, which will give us a figure 0f 21,979,330,560 tonnes of gaseous CO2. Just over a third of which is carbon. Based on this estimate, approximately 8 billion tonnes of carbon expelled into the atmosphere is directly attributable to one single human activity in a year. This does not include people running, jumping and shouting at Traffic Wardens. Nor does this figure include the CO2 and methane generated from one or the other end of the alimentary canal (Known as belching and farting). The actual figure is probably much higher because we as a species are only ‘At rest’ (With certain notable exceptions like hard core soap opera fans) for six to eight hours a day.
By comparison, emissions from other human activities worldwide (Fossil fuel burning etc.) were (1994 Pre Kyoto) estimated at 8+ billion tonnes of carbon. With all this breathing, belching, farting and shouting and running about, the total is probably closer to 12 billion metric tonnes of atmospheric carbon. Don’t even ask me about the contribution by livestock and wild animals. That’s probably another ten billion tonnes without so much as blinking. Add half as much again if a wildlife photographer who has farted at the wrong moment spooks them. Huge herds of Gnu’s in Africa are probably doing as much damage to the biosphere as all the pickup trucks in the USA and Canada combined with all China’s manufacturing output.
If this truly is the cause of the rise of global temperatures, and not simply a periodic increase in solar activity, you may quite justifiably ask how can we help? How can we reduce this awful toll on our precious blue green planet? My view is that every little helps. You can help by being calm. By planting trees and other plants to help ‘lock up’ atmospheric carbon. By not getting upset and raising your voices. By not exerting yourselves making angry gestures and empty threats, thus increasing your CO2 output and stress levels. Not shouting at me for example after I’ve caught you on double yellows might help. Just calm down and think of the planet that you’re saving. At least until I’m out of earshot.
P.S. According to some sources, it was even hotter back in Roman times than it is now. Being an adaptable person I have just planted some grape vines and a new fig tree in my garden, just in case. God bless, goodnight, and don’t forget your sunscreen.