[quote]kroby wrote:
CELTIC DEVIL, here’s another straw…
World Population and Global Warming
L. David Roper
http://arts.bev.net/roperldavid
It is well established that carbon dioxide and the Earth?s average temperature form a mutual positive feedback system. (http://www.roperld.com/science/CO2_Temp.pdf)
As far as I can tell the figures given (see below) for the emissions of carbon dioxide by
“human activities” does not include the carbon dioxide breathed out by humans. This short paper is an attempt to quantify the amount of carbon dioxide emitted by humans breathing and to compare it to the emissions due to other human activities.
Carbon Dioxide Emissions by Breathing of Humans
Each day the average person breathes about 15,000 liters, or approximately 35 pounds, of air.
(Toxicology - PhD Programs - Graduate Education - Education - University of Rochester Medical Center) Since air is 21% oxygen (molecular weight 16) and 78% nitrogen (molecular weight 14) by volume, oxygen is 23.5% by weight and nitrogen is 76.5% by weight in air. So the amount of oxygen breathed in per day by the average person is 35*0.235 = 8.2 lbs.
The molecular weight of O2 is 32 and the molecular weight of CO2 is 12+32=44. Therefore, humans emit 44x8.2/32 lbs = 11.3 lbs of CO2 every day or 4127 lbs = 2.1 tons per year per person.
In 2005 the Earth population was about 6.66x109. So the emitted CO2 per year by their breathing was about 14x109 tons.
In 2002 CO2 emissions due to human activities were 25x109 tonnes = 27.6x109 tons. Breathing adds about 14x109 tons, or about 51% more. (http://www.unep.org/geo/yearbook/yb2006/077.asp)
Globally, annual average emissions of carbon dioxide per capita due to human activities (other than breathing) have been fairly stable since 1990. For 2002, this figure was up to 3.93 tonnes from 3.85 tonnes in 2001.
http://www.unep.org/geo/yearbook/yb2006/077.asp Per capita CO2 emissions for 2002 = 3.93 tonnes/person = 4.33 tons/person. Breathing adds about 48% more (2.1 tons per person per year)
It appears that a figure of 50% increase of CO2 emission over the emission due to human activities is caused by the breathing of the huge number of people on Earth.
Do the emissions calculated as due to “human activities” include animals used for food and labor? If not, the effect of a high human population will be much larger.
This calculation just adds to the realization that the global-warming problem is, in essence, a population-explosion problem. Global warming may be one of nature?s ways to decrease human population.
For the long term the best way to reduce global warming is to reduce human population in a benign way by educating women and providing world-wide free contraception information and devices. If humans do not consciously do that, nature will do it due to the effects of global warming, the decline of petroleum extraction and the eventual entry into the next 115,000-year Major Ice Age.
(See http://www.roperld.com/science/HumanFuture.pdf .)
Do your part and stop breathing.
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Too bad Mr Roper didnt do his research. People breathe out only 0.57 kg of CO2 per day according to my calculations.
From Respiratory system - Wikipedia “In an average resting adult, the lungs take up about 250ml of oxygen every minute while excreting about 200ml of carbon dioxide. During an average breath, an adult will exchange from 500 ml to 700 ml of air.”
So per day, we excrete 200 * 60 * 24 = 288000 ml or 288 liters of CO2.
From http://www.newton.dep.anl.gov/askasci/chem00/chem00306.htm,
one kg of CO2 is 509.1 L
So we exhale 288/509.1 = 0.57 kg of CO2 every day. Thats 208 kg every year (0.23 US tons).
Using his figures for world population, the total amount of CO2 emitted is 1.5e9,
a factor of 10 smaller than the number he provides, making breathing safe for everyone again.