DEEPENING: Climate Change
In thinking about climate change, we need to be clear about the
difference between climate and weather.
A working definition is that climate is the description of the weather's
long-term behaviour. In describing climate we are interested not
only in averages of temperature and rainfall, but also in extremes
and how often they happen.
We are also interested in a wide range of meteorological measurements,
such as solar radiation, wind, air pressure and cloud over.
What determines climate?
As we move from the equator towards the poles the sun's rays strike
the earth at an increasingly shallow angle, with a corresponding
decrease in intensity.
The poles are therefore cooler than tropical regions.
Heat is redistributed by ocean currents and the global wind system,
reffered to as the general circulation, which blows through the
The pattern of these winds would be relatively simple except that
the earth's rotation and topography break up the wind systems into
different cells and produce the characteristic pattern of prevailing
The general circulation creates different weather patterns, determining
whether a point on the earth will be wet, dry, cold, warm, sunny,
cloudy, stormy or relatively calm.