The United Kingdom Environmental Change NetworkECNLSMAL.jpg (7249 bytes)


Factors Affecting Climate

 

There are many different factors that affect climate around the world.

The most important factors are:-

 

 

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 continent. 

 

Ocean Currents

 

mosaic2.gif (57604 bytes)

 

The Ocean Currents of the World

currents.gif (18712 bytes)http://www.itl.net

 

 

 

 

cean currents can increase or reduce temperatures.   The diagram to the left shows the ocean currents of the world.  The main ocean current that affects the UK is the Gulf Stream.  

Can you see where the gulf stream is?

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's 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.

 

The chart below was the first chart drawn of the Gulf Stream.  It was drawn by Benjamin Franklin in 1770.

 

The Gulf Stream - As Drawn By Benjamin Franklin

gulfstr.gif (59372 bytes)

http://www.cnmoc.navy.mil.educate

 

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 the Netherlands will be cold and dry in winter.  Britains prevailing winds come from a south westerly direction over the Atlantic.  The winds are cool in the summer and mild in the winter.

 

Relief

 

Climate can be affected by mountains.

 

Mountains receive more rainfall than low lying areas because the temperature on top of mountains is  lower than the temperature at sea level.  That is why you often see snow on the top of mountains all year round.  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. 

 

Proximity To The Equator

 

The proximity to the equator affects the climate of a place.  The equator receives the more sunlight than anywhere else on earth.   This is due to its position in relation to the sun (see right).  The diagram shows that the equator is hotter because the sun has less area to heat.  It is cooler at the north and south poles as the sun has more area to heat up.  It is cooler as the heat is spread over a wider area. 

The Earth's Position in Relation to the Sun

sunheat.gif (15271 bytes)

http://www.itl.net

 

El Nino

 

El Nino, which affects wind and rainfall patterns, has been blamed for droughts and floods in countries around the Pacific Rim.  El Nino 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 (see below)

 

Devastation Caused by a El Nino-generated tornado in Florida

_106098_el_nino_tornado_damage_florida_300.jpeg (13057 bytes)

http://news.bbc.co.uk

 

Smog In Indonesia

_106098_SMOG_IN_INDONESIA150.jpeg (9271 bytes)

http://news.bbc.co.uk

 

El Nino Causes Forest Fires in Brazil

_106098_el_nino_rain_forest_fire_150.jpeg (4677 bytes)

http://news.bbc.co.uk

 

Human Influence

 

The factors above affect the climate naturally.  However, we cannot forget the influence of humans on our climate.  We have been affecting the climate since we appeared on this earth millions of years ago.  In those times, the affect on the climate was small.  Trees were cut down to provide wood for fires.  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 in the atmosphere.  The number of trees being cut down has also increased, meaning that the extra carbon dioxide produced cannot be changed into oxygen. 

 

The affects on the climate can be seen in the next tutorial entitled 'Climate Change.'

 

button16.gif (2733 bytes)

 

You have now finished the tutorial on Factors Affecting Climate.  If you want to choose a new tutorial, click the button below.

 

button23.gif (2722 bytes)