Nancy LC
Fri, Dec-22-06, 12:19
http://www.newscientist.com/blog/environment/2006/12/carbon-sequestration-in-obese-humans.html
Carbon sequestration! That is, removing C02 from the air and storing it. Kind of like trees do.
Climate change and rising obesity are pressing issues of global concern. Simple calculations, outlined here using data for the US as an example, show that the latter may partially mitigate the former.
Emissions of the greenhouse gas carbon dioxide in the US from burning fossil fuels rose from 1415 million tonnes in 1994 to 1582 MT in 2002. Over the same period the mean body mass index of US adults (aged 20 years and over) rose from 26.5 to 28.1 for women and 26.7 to 27.8 for men.
These BMI increases reflect additional fat deposits of 3.3 kg and 2.3 kg (7.3 and 5.1 lbs) respectively per person. At a population level, these increases along with adult population growth (from 187.7 million to 206.6 million) amount to an additional 1.03 million tonnes of fat on the collective adult American skeleton.
Human fat is approximately 76% carbon by mass so, over the period considered (which includes the period of negotiation and signature of the Kyoto treaty) US citizens sequestered the equivalent of 2.9 million tonnes of carbon dioxide about their person.
Development of techniques to capture carbon dioxide is favoured in some quarters over imposition of emission restrictions that may be economically burdensome. Human sequestration could be one minor contribution: if in 2002 US adults had burnt off sufficient fat (2.2 MT) to reach the midpoint of the 'normal' BMI range (18.5 to 24.9) this would have released the equivalent of 6.1 MT of CO2.
Although this is a small amount compared to the country's total emission that year (0.4%), it is larger relative to domestic emissions. It is of the order of the amount forecast to be saved from the domestic sector in the UK by uptake of windpower microgeneration (0.3%).
Carbon sequestration! That is, removing C02 from the air and storing it. Kind of like trees do.
Climate change and rising obesity are pressing issues of global concern. Simple calculations, outlined here using data for the US as an example, show that the latter may partially mitigate the former.
Emissions of the greenhouse gas carbon dioxide in the US from burning fossil fuels rose from 1415 million tonnes in 1994 to 1582 MT in 2002. Over the same period the mean body mass index of US adults (aged 20 years and over) rose from 26.5 to 28.1 for women and 26.7 to 27.8 for men.
These BMI increases reflect additional fat deposits of 3.3 kg and 2.3 kg (7.3 and 5.1 lbs) respectively per person. At a population level, these increases along with adult population growth (from 187.7 million to 206.6 million) amount to an additional 1.03 million tonnes of fat on the collective adult American skeleton.
Human fat is approximately 76% carbon by mass so, over the period considered (which includes the period of negotiation and signature of the Kyoto treaty) US citizens sequestered the equivalent of 2.9 million tonnes of carbon dioxide about their person.
Development of techniques to capture carbon dioxide is favoured in some quarters over imposition of emission restrictions that may be economically burdensome. Human sequestration could be one minor contribution: if in 2002 US adults had burnt off sufficient fat (2.2 MT) to reach the midpoint of the 'normal' BMI range (18.5 to 24.9) this would have released the equivalent of 6.1 MT of CO2.
Although this is a small amount compared to the country's total emission that year (0.4%), it is larger relative to domestic emissions. It is of the order of the amount forecast to be saved from the domestic sector in the UK by uptake of windpower microgeneration (0.3%).