"Definition
Climate Change
Climate change is any substantial change in Earth’s climate that lasts
for an extended period of time. Global warming refers to climate change
that causes an increase in the average temperature of the lower atmosphere. Global
warming can have many different causes, but it is most commonly associated
with human interference, specifically the release of excessive amounts of
greenhouse gases. (EPA, 2006)
Greenhouse gases, such as carbon dioxide (CO2), methane (CH4), water vapor,
and fluorinated gases, act like a greenhouse around the earth. This means that
they let the heat from the Sun into the atmosphere, but do not allow the heat
to escape back into space. The more greenhouse gases there are, the larger
the percentage of heat that is trapped inside the earth’s atmosphere. The
earth could not exist in its present state (that is, with life) without the
presence of some naturally occurring greenhouse gases, such as CO2, CH4,
and water vapor.
Without any greenhouse gases no heat would be trapped in atmosphere, so the
earth would be extremely cold. (NASA, 2002)
Naturally occurring greenhouse gases (not fluorinated gases)
are good in naturally occurring amounts; it’s when people start contributing
excessive amounts of them that greenhouse gases become a problem. With
excessive greenhouse gas buildup, the earth’s atmosphere warms to unnatural
temperatures which causes, among other things, sea level to rise. Global
warming also causes sea surface temperatures to rise, precipitation patterns
to change, etc.. (NASA, 2002)"
Source: Global Warming: Definition
Written by YeSeul Kim, Erika Granger, Katie Puckett, Cankutan Hasar, and Leif
Francel, http://web.mit.edu/
