Climate in Canada !
Why does Canada have so much
Average Annual Temperature:
Alert, Nunavut (Ellesmere Island) : -18°C
Pelee Island, Ontario: 9°C
Yellowknife, NWT: -5°C
Four Basic Facts:
1. Canada extends for a great distance from north to south
2. Different elevations produce different climate conditions
3. Coastal regions have different climates from inland regions
4. Wind and pressure systems move weather conditions from
one part of the country to another
Weather vs. Climate
Weather: Day to day condition of the atmosphere,
- short term – 5 to 7 days
- small area - cities
- difficult to predict – 5 day forecast
Ex. Temperature, humidity, precipitation, wind speed, cloud
cover, air pressure.
Climate: Patterns of weather which have occurred over a
long period of time
- long term - years
- large areas – countries, continents, the globe
- easy to predict – summer, winter etc
Ex. continental climate, maritime climate, arid climate.
0 80 Precip
J F M A M J J A S O N D
TORONTO J F M A M J J A S O N D
Temp (oC) -5 -4 0 4 10 16 19 17 14 9 2 -1
Precip(mm) 56 53 53 56 56 61 76 56 58 56 58 56
• Vancouver is further north than Toronto yet it is
warmer and wetter in winter.
• Montreal is just a little bit north of Toronto yet it
is much colder in winter
Factors that affect Climate:
Winds and Air Masses
Solar energy delivered by sunlight varies with
latitude - Intensity.
• At higher latitudes (ie. north pole), the
solar energy is less concentrated, spread
over a larger surface area….cooler
• At lower latitudes (ie. equator), the solar
energy is more concentrated, spread over a
smaller surface… warmer.
Your position on the Earth determines the
amount of Solar Radiation (solar energy)
This is Intensity
The earth is always at a 23.5 degree tilt.
The northern hemisphere changes from being
tilted toward the sun (summer) to being tilted away
from it (winter) – Duration.
Summer Solstice - most direct sunlight at most
northern point from equator. Days are longer. June
Winter Solstice - most direct sunlight at most
southern point from equator. Days are shorter.
Take a moment, and be Amazed, by the
This site shows what the Earth looks like at
THIS MINUTE from different perspectives (from
the moon, the sun, night side, map view)
Hint: Think about how our earth is tilted at this
time of year...
2. Ocean Currents
Warm and cold pockets or streams (currents) of water
that move throughout the ocean.
• If a cold ocean current passes by, it will cool the
• If a warm ocean current passes by, it will warm the
• Ocean currents affect precipitation
See Map page 147
Major Ocean Currents
Average Temperatures in Winter - the lines
are called Isotherms. Compare Toronto to
3. Winds and Air Masses
A large volume of air with almost the same
temperature and moisture throughout. An air mass
takes climate conditions from one place to another.
Eg. An air mass originating from the Arctic is cold and dry.
It moves southward and is carried by the westerly winds,
bringing cold dry air across Canada.
Front: The boundary between two air masses with different
temperature and and moisture content.
WARM FRONT – the leading edge of a warm air mass
COLD FRONT – the leading edge of a cold air mass
See Map page 147
are what effects
pressure, wind -
The weight of air – Air Pressure.
Low Pressure - associated with warm air that
has expanded and is rising.
High Pressure - associated with cold air that
has contracted and is falling.
Winds move from High pressure to Low
pressure - See Hadley cell.
See page 148
Winds – cont’d
The movement of air from an area of High Pressure to
Winds are created by differences in air pressure. Around
the world there are belts of low and high pressure. As
they move around each other, they create a well-
established pattern of prevailing winds that blow from
West to East in Canada.
Prevailing winds - Winds that blow in almost constant
direction at these latitudes. In Canada, the prevailing winds
blow from west to east. These are called “westerlies” and
move air masses that affect our climate.
Why do the winds not simply blow directly north and south
between these belts?
• Winds are affected by the rotation of the earth.
This is called the CORIOLIS EFFECT.
Instead of winds moving in one straight north/south line
they are deflected to the right in the NORTHERN
Hemisphere and to the LEFT in the SOUTHERN
This is due to the rotation of the earth (eastward).
Hence, we have “westerlies” instead of “northerlies”!
Winds (coriolis effect)
The earth rotates
eastward. This force
changes the expected
path of the wind.
4. Elevation (Altitude)
Elevation: refers to how high or low we are on the earth’s
surface. The earth’s surface is our source of heat. The sun heats
the earth and in turn the earth heats us.
Air heats up, becomes less dense, rises, air pressure drops,
air expands, and heat is lost…Now it will COOL…until it
Rate of Temperature Drop BEFORE condensation:
1 degree celsius / 100 meters
Rate of Temperature Drop AFTER condensation: 0.6
degrees celsius / 100 meters
Relief: refers to differences in elevation caused
by features on the landscape, for example, a
mountain range is type of relief. Even a small
barrier like a building can cause a temperature
Mountain ranges act as barriers to the movement
of air masses. They also cause precipitation to
occur (called Relief or Orographic Precipitation)
6. Effect of Large Bodies of
• Water heats up and cools down more slowly than
• In the summer, wind blowing from the water will be
• In the winter, wind blowing from the water will be
Places near large water bodies are MODERATE -
they do not get as cool or as warm as others
Maritime: Warmer and Wetter
Continental: Cooler and Dryer
Weather Maps: (Monday, Jan. 5, 2009)
Use of Icons
Note: The Westerlies push the weather
Location of the Jet
Stream, Cold and
Warm Fronts, High
and Low Pressure
Soil and Vegetation
• Soil is a naturally occurring, unconsolidated or
loose material on the surface of the earth, capable
of supporting life
• Soil is made up of four components (MOMA):
– Organic Material
Soil and Vegetation
• Vegetation is a general term for the plant life of
a region that grows naturally (which very much
depends on Soil quality and of course Climate)
• Canada is a country of grass and trees:
– Coniferous trees
– Deciduous trees
Tundra West Coast Forest
Boreal Forest Broad-leaved Forest
Grassland Mixed Forest
Parkland Cordilleran Vegetation
• An ecozone is an area of the earth’s surface that
has a unique combination of plants, wildlife,
climate, landforms, and human activities.
• If you were to overlay or combine the climate,
landforms, soil (and vegetation) maps of Canada
shown in this slideshow, you would see patterns
emerge resulting in Canada’s 15 terrestrial (land)
+ + =