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Global warming is the buzzword that
surrounds virtually all fields of science and technology.
The theory of global warming is based on the belief that
average atmospheric temperatures throughout the world have
been increasing and will cause major climate change.
The theory is based largely on the release of greenhouse
gasses, the majority of which are produced by humans.
The earth is heated by light radiation
from the sun. As happens on most of the planets in our
solar system, light energy hits the surface and it is
reflected back out into space
 to leave a natural energy
equilibrium. The earth is different to other planets
however because the atmosphere stops a proportion of the
energy leaving naturally. This is done by what are
known as greenhouse gasses such as water vapour, carbon
dioxide, methane, ozone and nitrous oxide. These gases
are present in the atmosphere naturally but since humans
first learnt to make fire we have been unbalancing the usual
levels. It is believed that the vast amounts of these
gasses that we now produce and release from simple tasks
such as driving our cars and heating our homes every day has
contributed to a .6˚ increase in
atmospheric temperature in the 20th century.
The main causes of
increased greenhouse gas emissions is thought to be the
burning of fossil fuels. Carbon dioxide, methane and
nitrous oxide are all released as a result of this process.
Deforestation is also a major factor as trees are a natural
filter for removing carbon in the atmosphere. Methane
gas is produced mainly from decay and the increase of cattle
farming and human waste products has led to a sharp
increase.
Computer models of future
climate change show greater increases for this century, with
anywhere from 2 to 6˚ increase before the year 2100.
It is believed that the world will suffer from this increase
in many more ways than just rising sea levels from the polar
ice caps melting. The natural world would be thrown
into disarray with crops failing, species extinction, new
and increased diseases, severe storms more frequent and
changing ocean currents among many many possibilities.
 Steps have finally been
taken in the last decade to attempt to limit and control
spiraling greenhouse gas emissions. The Kyoto
protocol, which came into effect in february 2005, is the
most notable of these steps. The agreement was signed
by 156 countries and by doing so they have pledged to reduce
the total greenhouse emissions by 5% of 1990 levels by 2012.
The important thing to
remember about global warming is that it is only a theory.
We know that the earth has undergone climate change in the
past and most sceptics believe that current rising
temperatures are just the beginning of another cycle in
earths history. This is because although we have much
data to support the theory, we have just as much to reject
it. What is for sure is that everything that humans
do, no matter how small, has an effect on other parts of our
constantly changing environment.
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