Geography of Western Canada

Precipitation

Precipitation

• The amount of precipitation a location receives depends on its distance from the sea and the prevailing winds

• Precipitation = drizzle, showers, heavy rain, hail, or snow — all have an impact on the location they fall

• Western Canada experience three types: orographic, convectional, and frontal

Orographic Precipitation

Orographic Precipitation

• The prevailing winds blow moist air onshore

• As the air hits higher land, the air is forced to rise

• When air rises it begins to cool

• When it can no longer hold all its water; it starts to condense and form clouds

• Orographic = affected by mountains

Convectional Precipitation

Convectional Precipitation

• Water in the ocean and lakes is warmed by the sun

• The air above becomes heated

• This makes the air less dense, so it rises; as it rises it cools

• Cool air can not hold as much water vapour = condensation occurs, gradually becoming clouds

Frontal Precipitation

Frontal Precipitation

• Two air masses of warm and cold air meet, causing a front

• When they meet, the less dense, warm air is forced above the denser, heavier cold air

• When air can no longer hold its water, clouds form