Canadian Geography 1202: Unit 1 CLIMATE Notes, Part 1
WEATHER: refers, generally, to day-to-day (short-term) conditions such as temperature, precipitation and wind activity.
Statements that are examples of weather:
- “It is very windy today.”
- “We are expecting 25 cm of snowfall overnight.”
- “It is extremely humid tonight”
- “It was -35° C yesterday”
CLIMATE: weather patterns over a long period of time (long-term).
Statements that are examples of climate:
- “It rains a lot in Vancouver”
- “Edmonton experiences hot summers and cold winters”
- “It is always warm near the equator”
FACTORS THAT INFLUENCE CLIMATE:
1. LATITUDE: The further north or south of the equator you go the colder it gets.
2. TILT OF EARTH: Because Earth is slightly tilted, the sun is more intense on certain parts of the surface at different
times of the year. For example the Northern Hemisphere is closer to the sun in June (summer) and further away
in December (winter).
3. WIND: Wind carried warm or cool air depending on where it is blowing from. Likewise, it can carry moist or dry
air as well.
4. OCEAN CURRENTS: Like wind, Ocean currents can carry warm or cool air depending on where it is coming from.
Ocean currents give coastal (maritime) communities moist, mild climates, generally speaking.
5. CONTINENTIALITY: Nearness to large bodies of water. Coastal communities generally have cool summers and
mild winters (narrow temperature range) with a lot of precipitation while interior (continental) communities
have a wider temperature range and less precipitation.
6. ELEVATION: the higher the elevation, the cooler the climate.
PRECIPITATION: atmospheric water phenomena that falls to Earth as a result of the condensation of atmospheric water
vapor. The main forms of precipitation include drizzle, rain, sleet, snow, and hail
THE THREE TYPES OF RAINFALL:
1. FRONTAL RAINFALL





Warm Moisture laden air meets
cold air;
warm air is less dense & is
forced up over the cooler, more
dense air;
warm Moisture laden air cools
at higher altitude;
cool air holds less moisture;
clouds condense and rain falls.
2. CONVECTIONAL RAINFALL






Usually occurs in hot areas like
tropics or continental summer;
sun heats the earth causing
large amounts of water to
evaporate;
hot air rises forming convection
currents (hence the name);
warm moisture-laden air cools
at higher altitude;
cool air holds less moisture;
consequently clouds condense
and rain falls.
3. RELIEF / OROGRAPHIC RAINFALL







Moisture laden air blows off the
sea;
it is forced up by mountains
(high relief);
air cools at higher altitudes;
cool air holds less moisture;
clouds condense and rain falls;
most rain falls on the
windward side of the relief;
leeward side is often in a dry
rain shadow because the
moisture has all been lost.
CLIMOGRAPHS
A climograph is a graphical representation of the basic climatic parameters, that is monthly average
temperature and precipitation, at a certain location. It is used for a quick-view of the climate of a location.
LATITUDE
The equator is 0°. The further north or south from the equator you go, the colder
it becomes. The most southerly point of Canada is about 41 oN near Point Pelee
in Lake Ontario. Most of Canada is north of 49°N. It is a long way north of the equator, and thus, it is
cool. The colder northern latitudes are due to the angle at which the sun’s rays strike the Earth. The
sun’s rays strike the equator in a very concentrated area, and thus, the rays only heat a small area of
the Earth’s surface. The heat energy from the sun is very intense at the equator. In contrast, the sun’s
rays at higher latitudes strike the Earth in a very spread out area…due, in part, to the Angle of
Incidence (about 23°). Since the same amount of energy in the sun’s rays must heat a larger area, the
area is cooler
TILT OF EARTH
<-----SUN
JUNE
DECEMBER