FACTORS INFLUENCING CLIMATE

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FACTORS INFLUENCING CLIMATE

• The factors that influence climate can be
  identified by using the following anagram J.
  BLOWER
• J. Jet Stream
• B Bodies of water
• L Latitude
• O Ocean currents
• W Winds and air masses
• E Elevation
• R Relief

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FACTORS INFLUENCING CLIMATE
JET STREAM

• The jet stream is a layer of fast moving (300
  500 km per hour), high altitude (20 25 km) air
  flow that forms an ever-changing boundary between
  cold air masses from the north and warm air
  masses from the south.
• The polar jet stream steers weather systems and
  storms across the country. The position of the
  jet stream helps determine what the climate is
  like in a particular place.
• The clash of the different air masses along the
  polar jet stream front can produce severe
  weather, including violent thunderstorms and
  tornadoes in many parts of the country.
• The jet stream flows from west to east.

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FACTORS INFLUENCING CLIMATE
The Jet Stream
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FACTORS INFLUENCING CLIMATE
BODIES OF WATER

• Large bodies of water heat up and cool down more
  slowly than land masses.
• These large bodies of water have a moderating
  effect on climate. That means that places
  located near large bodies of water experience
  cooler summers and warmer winters than places
  that are located far from large bodies of water.
• Places located along ocean coasts have a maritime
  climate. This means that the highest and lowest
  temperatures dont range very much and there is
  more precipitation.
• Places like the Prairies, which are located in
  the centre of the continent away from large
  bodies of water, have a continental climate. This
  means that the temperature range they experience
  is more extreme and climate conditions are drier.

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FACTORS INFLUENCING CLIMATE
BODIES OF WATER
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FACTORS INFLUENCING CLIMATE
LATITUDE

• Because Canada is a northern country, the
  latitude plays an important role in the general
  climate pattern.
• Generally, the further north you are, the colder
  and drier the climate. This is caused by two
  factors the ways the suns rays strike our
  planet and the curvature of the earth. The suns
  rays strike the planet in essentially parallel
  lines these rays are more concentrated at the
  Equator making that area very warm. When the
  same amount of the suns rays strikes the earth
  further north (in Canada) the heat is spread over
  a larger area because of the curvature of the
  earth.
• Because of the northerly location of the country,
  much of Canada is covered by the Subarctic and
  Arctic Climate Regions.

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FACTORS INFLUENCING CLIMATE
LATITUDE
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FACTORS INFLUENCING CLIMATE
OCEAN CURRENTS

• Both warm and cold ocean currents flow along
  Canadas coastlines.
• Warm ocean currents make places close to the
  coast warmer than normal for that latitude, while
  cold ocean currents make places close to the
  coast colder.
• The warm Gulf Stream current which flows
  northward from the Gulf of Mexico along the
  Atlantic coast helps bring cool, humid summers
  and short cool winters to that region. The warm
  Gulf Stream also meets the cold Labrador current
  in Atlantic Canada which results in more that
  average precipitation and fog throughout much of
  the year.
• On Canadas west coast, the coast of British
  Columbia is subjected to the warm North Pacific
  Drift current. This results in a very maritime
  climate with lots of precipitation and moderating
  temperatures. The Pacific Climate zone is the
  only climate zone in Canada where the average
  monthly temperatures are ALL above freezing
  (zero).

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FACTORS INFLUENCING CLIMATE
OCEAN CURRENTS
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FACTORS INFLUENCING CLIMATE
WINDS AND AIR MASSES

• An air mass is a large body of air with the same
  temperature and moisture characteristics
  throughout. The wind speeds and directions are
  also similar throughout the air mass. Generally,
  there are four air masses that influence the
  climate and weather in Canada polar maritime,
  polar continental, tropical maritime and tropical
  continental.
• Polar maritime air masses are formed in the north
  and over the water. They are generally cold and
  moist.
• Polar continental air masses are formed in the
  north over the land. They are cold and dry.
• Tropical maritime air masses are formed in the
  south and over water. They are generally warm and
  moist.
• Tropical continental air masses are formed in the
  south and over land. They are warm and dry.

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FACTORS INFLUENCING CLIMATE
AIR MASSES
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FACTORS INFLUENCING CLIMATE

• Wind is moving air the winds blow from areas of
  high pressure to areas of low pressure this is
  called the pressure gradient.
• In a low pressure area, the air tends to rise and
  in a high pressure area the air descends. When
  the air pressure is low, the skies are often
  cloudy and there is a good chance of
  precipitation. When the air pressure is high, the
  skies are generally clear and the weather is
  nice.
• The winds carry air masses across the country.
  When a warm air mass and a cold air mass collide,
  the warm air rises up over the cold air
  resulting in precipitation and storms.
• In Canada the prevailing winds (most common
  winds) are the westerlies which blow from west
  to east.
• The direction of the wind patterns is caused by
  the coriolis force a force that deflects moving
  air to the right from its direction of movement.
  This force results in the northeast trade winds,
  the westerlies and the polar easterlies.

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The prevailing winds in Ontario are the
Westerlies.
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ELEVATION

• Simply put, the higher the elevation the colder
  the temperatures. So, as you go up a mountain
  the temperatures decrease. Evidence of this is
  the fact that there is often snow on the highest
  mountain peaks. As you come back down the
  mountain the temperatures increase.
• The rate at which the temperatures increase or
  decrease is called the lapse rate. The average
  lapse rate is 1 degree change for every 100
  metres of elevation.

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ELEVATION
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FACTORS INFLUENCING CLIMATE
RELIEF

• Relief is the change of elevation and it can
  cause precipitation. As the mountains force the
  warm, moist air blowing across them to rise the
  water vapour in the air cools and condenses to
  form clouds. As more water vapour condenses the
  water droplets become to too heavy to stay aloft
  and fall as rain or snow. Most of the relief
  rainfall falls on the windward side of the
  mountain while the other side (away from the
  ocean) is the more protected leeward side of the
  mountain and has a much drier climate. This area
  is sometimes called the rain shadow area.
• Precipitation can also occur without mountains.
  For example, when two air masses collide one
  rises above the other and the air cools water
  vapour forms and falls as rain. Sometimes there
  an be precipitation without having two air masses
  or mountains. On warm sunny days, the heat from
  the sun can cause warm air to rise in
  convectional currents the water vapour
  condenses and it rains. The rainfall in Southern
  Ontario is caused by both the frontal system and
  by convection currents especially in the hot
  summer days.

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FACTORS INFLUENCING CLIMATE
RELIEF RAINFALL
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