FACTORS AFFECTING CLIMATE OF A PLACE.

Factors affecting climate tutorial
There are many different factors that affect climate
around the world. It is the varying influence of these
factors that lead to different parts of the Earth
experiencing differing climates. The most important
natural factors are:
distance from the sea
ocean currents
direction of prevailing winds
shape of the land (known as 'relief' or 'topography')
distance from the equator
the El Niño phenomenon .
It is now widely accepted that human activity is also
affecting climate, and that the impact is not the same
everywhere. For example, changes appear to be
happening faster near the poles than in many other
places. In this tutorial we will look at some of these
factors in more detail.
Distance from the sea (Continentality)
The sea affects the climate of a place. Coastal areas are
cooler and wetter than inland areas. Clouds form when
warm air from inland areas meets cool air from the sea.
The centre of continents are subject to a large range of
temperatures. In the summer, temperatures can be very
hot and dry as moisture from the sea evaporates before
it reaches the centre of the land mass.
Ocean currents
Ocean currents can increase or reduce temperatures. The
diagram below shows the ocean currents of the world
(view original source map ). The main ocean current that
affects the UK is the Gulf Stream.
Click the map to see a larger version
The Gulf Stream is a warm ocean current in the North
Atlantic flowing from the Gulf of Mexico, northeast along
the U.S coast, and from there to the British Isles.
The Gulf of Mexico has higher air temperatures than
Britain as it is closer to the equator. This means that the
air coming from the Gulf of Mexico to Britain is also
warm. However, the air is also quite moist as it travels
over the Atlantic ocean. This is one reason why Britain
often receives wet weather.
The Gulf Stream keeps the west coast of Europe free
from ice in the winter and, in the summer, warmer than
other places of a similar latitude.
Direction of prevailing winds
Winds that blow from the sea often bring rain to the
coast and dry weather to inland areas. Winds that blow
to Britain from warm inland areas such as Africa will be
warm and dry. Winds that blow to Britain from inland
areas such as central Europe will be cold and dry in
winter. Britain's prevailing (i.e. most frequently
experienced) winds come from a south westerly direction
over the Atlantic. These winds are cool in the summer,
mild in the winter and tend to bring wet weather.
The shape of the land ('relief')
Climate can be affected by mountains. Mountains receive
more rainfall than low lying areas because as air is forced
over the higher ground it cools, causing moist air to
condense and fall out as rainfall.
The higher the place is above sea level the colder it will
be. This happens because as altitude increases, air
becomes thinner and is less able to absorb and retain
heat. That is why you may see snow on the top of
mountains all year round.
Distance from the equator
The distance from the equator affects the climate of a
place. At the poles, energy from the sun reaches the
Earth's surface at lower angles and passes through a
thicker layer of atmosphere than at the equator. This
means the climate is cooler further from the Equator. The
poles also experience the greatest difference between
summer and winter day lengths: in the summer there is a
period when the sun does not set at the poles;
conversely the poles also experience a period of total
darkness during winter. In contrast, daylength varies little
at the equator.
El Niño
El Niño , which affects wind and rainfall patterns, has
been blamed for droughts and floods in countries around
the Pacific Rim. El Niño refers to the irregular warming of
surface water in the Pacific. The warmer water pumps
energy and moisture into the atmosphere, altering global
wind and rainfall patterns. The phenomenon has caused
tornadoes in Florida, smog in Indonesia, and forest fires
in Brazil.
El Niño is Spanish for 'the Boy Child' because it comes
about the time of the celebration of the birth of the
Christ Child. The cold counterpart to El Niño is known as
La Niña , Spanish for 'the girl child', and it also brings with
it weather extremes.
Human influence
The factors above affect the climate naturally. However,
we cannot forget the influence of humans on our
climate. Early on in human history our effect on the
climate would have been quite small. However, as
populations increased and trees were cut down in large
numbers, so our influence on the climate increased.
Trees take in carbon dioxide and produce oxygen. A
reduction in trees will therefore have increased the
amount of carbon dioxide in the atmosphere.
The Industrial Revolution, starting at the end of the 19th
Century, has had a huge effect on climate. The invention
of the motor engine and the increased burning of fossil
fuels have increased the amount of carbon dioxide (a
greenhouse gas - more on that later) in the atmosphere.
The number of trees being cut down has also
increased, reducing the amount of carbon dioxide that is
taken up by forests.