ENVIRONMENTAL PROBLEMS - Energy: What Everyone Needs to Know - page 73

istics of such gases. For example, one molecule of CH 4 is 21 times more effective
than one molecule of CO 2 in blocking such emissions.
As a consequence, the contribution to global warming from different green-
house gases in 2005 was the following: CO 2 contributed 76% (60% from fossil
fuels use and 16% from deforestation), CH 4 contributed about 16%, N 2 O about
6%, and the fluorinated gases contributed 2%.
In addition to that, the rate of emission of greenhouse gases is different for dif-
ferent gases: CO 2 emissions are increasing 0.4% per year, methane 0.8%/year, ni-
trous oxide 0.25%, and chlorofluorocarbons 4%/year. CO 2 originates mainly from
the burning of fossil fuel, methane from the biological degradation of organic
residues and waste (including animal and human wastes), and chlorofluorocarbons
are gases used widely in hairsprays, refrigeration, and air conditioners.
The major carbon emitters (CO 2 and CH 4 ) for energy production are the indus-
trialized countries (United States, Russia, Japan, Germany, Canada, United King-
dom, and a few others), but in developing countries (China, India, Brazil, Mexico,
and others) emissions are growing rapidly. In addition, deforestation emissions and
other forms of land-use change in developing countries are contributing signific-
antly to the emissions.
The origin of CO 2 emissions from final end use is indicated in Table 8.1 .
Table 8.1 The origin of CO 2 emissions
* Others include commercial, public services, agriculture/forestry/fishing