Download 3-The Climates of Canada

1.4
 Most of Canada lies above 49 degrees north latitude
 Inland areas experience a continental climate
 temperature extremes (high and low)
 low precipitation
 Coastal areas have a maritime climate
 mild temperatures and high precipitation
 The Atlantic Coast has more severe climate than
coastal BC
 Result of wind blowing from inland creating
greater differences in temp. and precipitation
 1. Latitude
 2. Altitude
 3. Distance from the Sea
 4.Wind Direction
 5.Ocean Currents
 The further you move away from
the equator, north or south, the
cooler the temperature
 Why? The sun’s rays are dispersed
over a larger area of land as you
move away from the equator
 Also affects the length of day and
night
 The higher it is from sea level, the cooler the temperature.
 Why? As elevation increases, the air becomes less dense. Less dense air cannot hold as
much heat as dense air and thus temperature decreases.
 Generally temp. drops 1 degree Celsius for every 150 meter rise in altitude
 Snow still appears on mountains even in the summer.
 Land surface heats and cools more quickly than
water
 Because Canada is so large, temperature can
swing between extremes – high in summer, low
in winter
 However, temperature of west coast of Canada
is moderated by proximity to the sea
 Less difference between summer and winter
temperatures
 Winds blowing from water
increase moderating effect of
water
 Prevailing winds are those that
come from one direction
 In Canada those are mostly
westerlies (from the west) or
northerlies (from the north)
 Warm westerlies cause BC to have
milder climate
 Ocean currents are either warm or cold
 depending on where they originate
 Warms or cools the air moving over it
 Affects temperature of land
 West coast, with a warm current, has a
mild climate
 Newfoundland and Labrador, next to the
cold ocean current, has much harsher
winters
 Canada’s precipitation includes rain, snow, hail
 What determines the amount of precipitation an area receives?
 Distance from the sea
 Prevailing winds
 Western Canada faces 3 types of precipitation
 1. Orographic
 2. Conventional
 3. Frontal
 Orographic =mountain
 Westerly winds push warm moist pacific air up against mountains
 Rising air cools, vapour condenses, clouds form and rain falls
 As the air descends the eastern slope the air becomes warm and dry; this area is called the rain
shadow
 Caused by convection currents in
atmosphere
 takes place mostly in Prairies and Canadian
Shield during the hot months
 As the ground warms, the air is warmed,
expands and rises
 Meets cool air which also warms, rises and
cools to form
 Forms clouds of rain or hail which falls
back to Earth
 Cold polar air from north and warm
tropical air from south cannot mix
 Their line of contact is called a
“front”
 Because tropical air is less dense
than cold air, it rises over it
 As it rises it condenses and forms
clouds which result in prolonged
precipitation
 More of this type during winter
months
 Most of the rivers begin in the cordillera
 Constant flow of water results from high precipitation
and melting of snowpack
 Rivers flow west and east out of mountains and
continue until they reach major body of water
(Pacific Ocean, Hudson’s Bay)
 Join with other rivers and lakes and drain the land
 Areas drained by one river system are called a
drainage basin/watershed
 Formed as rivers carry eroded material away
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Complete Q’s #1-3 on pg. 107 (HW Check next class!)