ence/earth-sci/weather-101-sci/

Canada’s climate varies based on geography, from perma-frost in the north to four distinct seasons towards the equator. In this region the temperature can climb up to 35° C in the summer and descend to a chilly -25 ° C during winter.

Canada’s climate and environment are one of the main reasons that Canada is such a successful country. The blend of natural resources and climate sustains us. The seasons dictate the look of the land: according to whether the natural environment is in a state of dormancy or growth.

Canada’s climate is characterized by its diversity, as temperature and precipitation differ depending on where you are and what time of year it is. Other than the North where it is above freezing for only 2-3 months in the year, most Canadian cities are within 300 km of the southern border, where mild springs, hot summers and crisp autumns are common.

So far, we have broken down Canada into regions based on a single factor which was landforms. Our next goal is to divide Canada up into climate regions and to determine why each region within Canada has its own unique climate. To fully understand this concept we must start by distinguishing the difference between WEATHER and CLIMATE.

- Is a result of day-to-day conditions of the atmosphere - Includes the temperatures outside, if it is hot/cold, raining/snowing, windy/humid, etc.

- Weather conditions of a place averaged over a long period of time (usually 30 years!) - Different parts of Canada have different climates Example: Toronto compared to Vancouver

Defining Climate… Temperature Precipitation Relative Humidity Wind Special Weather Conditions

Temperature Where the temperatures are extremely cold, the air is generally very dry. Therefore, when no wind is present, the coldest climate of Canada is surprisingly bearable … when one wears appropriate clothing, of course! The temperature extremes Canadians experience can range from as low as -65C in the Northern Cordillera, in winter, to close to 50C in the Prairies, in the summer.

Precipitation Precipitation is not equally distributed over the Canadian territory, from one region to another, as well as from one season to another. The Pacific region, and the Atlantic provinces receive the most, while the southern Prairie region receives the least.

Relative Humidity In the summer, a temperature of 30C, can feel like 45C when it's very humid. This creates sticky and sweaty conditions. The Southeastern climate of Canada is noted for these uncomfortable combinations! (Think of Toronto!)

Wind The wind chill factor will lower the effective temperature (for exposed flesh) much below the ambient (actual) temperature

Special Weather Conditions The southern and southeastern regions of Canada experience thunderstorms, some of them severe, in the summer. Lastly, a few tornadoes occur, mostly in the southern interior, in the summer. The occasional hurricane will move up the North- American East coast, as far up as the Atlantic provinces, in early autumn.

Why do Different Parts of Canada experience different climates?

1.The further a region is from the equator, the cooler the climate 1.The closer a region is to the equator, the warmer its climate

Concentrated Spread Out Result: the sun’s rays travel through more atmosphere and therefore are weaker!

Why do Different Parts of Canada experience different climates?

Relief: The difference in elevation on the Earth’s surface 20 m 12, 000 m

- The mountain has a higher relief than the hill 20 m 12, 000 m - B/c of a mountain’s high relief, it can act as a barrier to the movement of air masses

Warm air mass OCEAN WESTERN CORDILLERA BARRIER Cold and DRY weather

Vancouver Calgary

-The Higher the elevation, the colder the temperature Example: if you were hiking up a mountain, you would notice that the temperature drops Temperature decreases as you  10°C - 10°C

-As air rises it expands and releases energy (heat), because there is less air pressure - The weight of air above you

Vaporization!

Air mass rising over mountain _ _ _ _ _ _ _ _ _ _ _ _ _ 1700m Condensation Level Step 1 – How far will the air rise before condensation begins? = 1700m – 0m = 1700m Step 2 – How much will the temp. drop in this distance? (Rate of cooling = 1°C/100m) = 1700m x 1°C / 100m = 17°C Step 3 – How far will the air mass rise after condensation begins? = 2200m – 1700m = 500m 2200 m Sea Level – 0m (Temperature = 21°C)

Air mass rising over mountain _ _ _ _ _ _ _ _ _ _ _ _ _ 1700m Condensation Level IS THERE SNOW AT THE TOP OF THIS MOUNTAIN?? NO Step 4 – How much will the temp. drop in this distance? (Rate of cooling is 0.6°C /100m) = 500m x 0.6°C / 100m = 3.0°C Step 5 – What will the temperature be at the top of the mountain? = 21°C - (17°C + 3°C ) = 1°C 2200 m Sea Level – 0m (Temperature = 21°C)

Air mass rising over mountain _ _ _ _ _ _ _ _ _ _ _ _ _ 900m Condensation Level Step 1 – How far will the air rise before condensation begins? = 900m – 0m = 900m Step 2 – How much will the temp. drop in this distance? (Rate of cooling = 1°C/100m) = 900m x 1°C / 100m = 9°C Step 3 – How far will the air mass rise after condensation begins? = 1400m – 900m = 500m 1400 m Sea Level – 0m (Temperature = 26°C)

Air mass rising over mountain _ _ _ _ _ _ _ _ _ _ _ _ _ 900m Condensation Level IS THERE SNOW AT THE TOP OF THIS MOUNTAIN?? NO Step 4 – How much will the temp. drop in this distance? (Rate of cooling is 0.6°C /100m) = 500m x 0.6°C / 100m = 3.0°C Step 5 – What will the temperature be at the top of the mountain? = 26°C - (9°C + 3°C ) = 14°C 1400 m Sea Level – 0m (Temperature = 26°C)