gases and global warming
Greenhouse gases include carbon dioxide, methane, water vapour
and nitrous oxide. These are all naturally occurring gases
in the Earth’s atmosphere, but are also by-products
of industrial processes. CFCs are another form of greenhouse
gas, but are produced solely in industrial processes and do
not occur naturally.
Greenhouse gases cause the Earth to warm up because their
particles cause radiation to act in a particular way. The
gases allow radiation from the sun to pass through the Earth’s
atmosphere without any problem. The Earth, in turn reflects
back this radiation, but in so doing, the wavelength is changed.
Reflected radiation then meets particles of greenhouse gas
on its way out again and is absorbed by the particle. This
causes the particle to become agitated, and this warms up
the greenhouse gas. This then gives rise to a warm blanket
effect around the planet, thus raising the surface temperature.
These greenhouse gases absorb some of the Sun’s energy,
warming the atmosphere near the surface just enough to support
life. Some scientists believe that emissions of greenhouse
gases are causing too much energy to be trapped and increasing
the temperature too much.
Gasses like methane and CFCs are much more efficient at trapping
energy than carbon dioxide, but as it makes up a greater part
of the atmosphere, it is the main cause for concern. The combustion
of fossil fuels is the major source of manufactured carbon