Canada’s ClimateFebruary 20, 2015

Often defined as average weather, when weather means the current state of the atmosphere

Because of Canada’s size, Canada has many different climates

What is climate?

Identify 6 factors that affect climate and explain how each affects climate

With a partner…

1.Latitude2.Ocean Currents3.Winds and air masses4.Elevation (Altitude)5.Relief6.Near Water

6 Factors that Affect Climate

Latitude is the distance a place is located from the equator As latitude increases, the average annual temperature

decreases

1. Latitude

The temperature of an ocean current affects the temperature of the air that passes over it.

Warm ocean currents raise the temperature of nearby land, while cold currents lower the temperature. Warm Currents = warmer climate Cold Currents = cooler climate

2. Ocean Currents

Ocean Currents (cont’d)

An air mass is a large volume of air that moves over an area of land bringing with it, the weather conditions of the area it formed over

Air masses are characterized based on their moisture content and temperature.  Moisture:

Maritime – wet (formed over water) Continental - dry (formed over land) 

Temperature: Tropical – hot (formed near the tropics) Polar – cold (formed between 55N and 66N) Arctic – very cold (formed over the Arctic)

Wind is created by differences in air pressure in the atmosphere (winds move from areas of high pressure to areas of low pressure). Low pressure systems are the result of warm air rising; high pressure systems are created by cool air sinking; associated with clear and favourable skies.

Prevailing Winds are the well-established patterns of winds blowing from west to east over Canada. Called the “westerlies”

The jet stream is the west to east movement of air in the mid-latitudes flowing at speeds of up to 400 km/hr at an altitude of between 8000 and 15,000 metres.

3. Winds and Air Masses

Winds and Air Masses (cont’d)

The height above the earth’s surface (or altitude)

As elevation increases, the average annual temperature decreases.

4. Elevation

The difference in the height of an area of the earth’s surface

Windward side: cool, moist; Leeward side: warm, dry

5. Relief

Proximity to a large body of water (i.e. oceans, or large lakes)

Bodies of water are a source of moisture. Winds carry moisture over nearby land, creating a moderating effect on climate.

Places located near a body of water are called maritime climates (i.e. Halifax, Nova Scotia) and experience mild temperatures (small temperature range) and large amounts of precipitation (more than 1000mm).

Places located far from a body of water are called continental climates (i.e. Regina, Saskatchewan) and experience cool temperatures (large temperature range) and small amounts of precipitation (below 1000mm).

6. Near Water

Colour and label a map of Canada’s Climate Regions

Interpret climate graphs in Fig. 13-15 using the guidelines on page 156

Use the information in Fig. 13-16 on page 158 to complete the climate graphs**

Activity: Climate Graphs