WHAT AFFECTS CLIMATE IN CANADA? CLIMATE PROCESSES WHAT AFFECTS CLIMATE IN CANADA?

WEATHER: the day-to-day characteristics of atmospheric conditions in a specific area. What impacts weather in your area? Air Temperature Wind Air Pressure Humidity Precipitation Cloud Cover These elements over a short period of time in a small area are weather. CLIMATE: long term weather patterns over a large area. WEATHER VS. CLIMATE

CLIMATE CONSIDERATIONS Climate is concerned primarily with two main areas that we track and measure. What do you think they are? TEMPERATURE PRECIPITATION CLIMATE CONSIDERATIONS

PARTS OF A CLIMATE GRAPH note title * Avg. precipitation avg temperature month PARTS OF A CLIMATE GRAPH

ABOUT CANADA’S CLIMATE Why is Canada’s climate special compared to other countries in the world? Very large – thus, a variety of climates within our borders. The numerous of climates we have vary widely. We have both extensive coastal and inland climate regions. ABOUT CANADA’S CLIMATE

DETERMINING CLIMATE We’ll take a look at them in more detail… There are 6 primary factors that determine climate. A handy mnemonic can be used to remember them! Latitude Ocean Currents Winds, air masses, and jet streams Elevation Relief Near Water We’ll take a look at them in more detail… DETERMINING CLIMATE

Latitude and climate can be explained in one easy step: “Temperature decreases as latitude increases.” Thus, the farther away from the equator you are, the colder it will be. Why do you think? Also, very easy if you have the right attitude! Just saying… LATITUDE

Temperature of an ocean current will affect the air above it as it passes. These currents have a moderating effect on the coasts. Currents are also have a great deal to do with precipitation (rain, snow, etc.) levels. Note that the water flows in an ongoing cycle with temperatures changing based on latitude… OCEAN CURRENTS

E.g. The cold Labrador Current cools the air along the Labrador Coast, while the Gulf Stream flowing northwards warms the areas it contacts. These two currents meet over the Grand Banks to create an area that has over 100 days of fog each year! OCEAN CURRENTS

An air mass is a large volume of air with a consistent temperature and level of moisture throughout. Air masses move from areas of high pressure to low pressure – this creates wind (Coriolis Effect). Air masses have characteristics retained from where they were formed. There are two categories of air mass: Maritime Air Masses are formed where? Continental Air Masses are more likely to be what? WIND AND AIR MASSES

In Canada, our prevailing (primary) winds move air masses from the west to the east (called Westerlies). WIND AND AIR MASSES

As altitude (height above sea level) increases, the temperature decreases. This is why you see “snow-capped mountains”. However, warm, moist air also rises and the condensation from its moisture creates clouds! ELEVATION

As a general rule, air cools by 1 degree Celsius for every 100m a location is above sea level. Condensation happens at heights because cooler air can’t contain moisture as effectively. ELEVATION

Mountains form a natural barrier (called relief) that cause air masses to rise, and cool as a result. As air is forced to rise, it expands as gravity decreases. This leads to condensation (clouds) and causes the air to be much thinner. This happens on the windward (facing the wind) side of the mountain. As air descends down the other side of the mountain (leeward side), it will become dryer and temperatures will increase. RELIEF

Large water bodies, like oceans and lakes, heat up and cool down much more slowly than land masses. Thus, water bodies also have a moderating affect on the climates of the land masses near to them. During summer, wind blowing over water cools the land. In winter, winds coming from water will warm the land. NEAR WATER

CLIMATE CLASSIFICATIONS CANADIAN CLIMATE TYPICAL CLIMATE TEMPERATURE RANGE ANNUAL PRECIPITATION Continental Warm/Hot Summer Cold Winters -25 to +50 °C (Large Range) 200 to 1000mm (Low/Moderate) Maritime Cool/Warm Summers Cool Winters -10 to 30 °C (Small Range) 1000 to 2500mm (Moderate/High) CLIMATE CLASSIFICATIONS

RECOMMENDED READING Textbook: pages 56 – 65 Remember to check out this link for help with climate graphs for Canadian cities: http://climate.weather.gc.ca/climate_normals/index_e.html RECOMMENDED READING