Social Studies. Chapter 2 Canada s Physical Landscape

Transcription

1 Social Studies Chapter 2 Canada s Physical Landscape

2 Introduction Canada s geography its landforms and climate - has a great impact on Canadians sense of identity.

3 Planet Earth The earth is divided into layers Core the center It has 2 layers: a hot solid inner layer and a liquid outer core Mantle the middle layer of the earth; made up of MAGMA (melted rock). When Magma erupts from the Earth through an opening or crack it is called Lava. Crust - the solid outer layer of the earth

4 Planet Earth

5 The Theory of Continental Drift and Plate Tectonics First suggested by the German geologist and meteorologist Alfred Wegener in The theory states that the Earth's crust is divided into plates that move slowly due to CONVECTION CURRENTS in the mantle. Wegener hypothesized that there was a gigantic supercontinent 200 million years ago, which he named Pangaea, meaning "All-earth".

6 Evidence to support Wegener s theory: the fit of the land masses presence of similar fossils in rocks separated by an ocean Matching rocks on the either side of the Atlantic

7 Continental Drift: Movement of the Earth s continents on the Earth s plates Plate Tectonics: Concept of convection currents and plate movement. The theory that plates move together to cause earthquakes, and form volcanoes and mountains.

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10 Canada s Crust Located on the northern part of the North American Plate Important points: Moving 2-4cm a year to the west, separating from the Eurasian plate creating a separation on the sea floor called the MID-ATLANTIC RIDGE

11 The Pacific Coast is located on the western edge of the North American Plate. The Pacific Plate moves in a northeasterly direction. This creates a SUBDUCTION ZONE an area of the earth s crust where one plate slides beneath another. This creates volcanoes and cause earthquakes to occur.

12 b_odo-q&feature=related British Columbia experiences approximately one-fifth of Canada s thousand or so earthquakes. Fault: The area where two plates meet

13 What are Landforms? Landforms are the topography, or natural features, of the land s surface. A landscape is an area s landforms together with its cover of vegetation, water, ice, and rock. Landscape also includes the activities of humans and other animals.

14 There are urban and rural landscapes. Landscapes directly affect people s lives, influencing what they eat, how they earn a living, and many other factors of daily life.

15 Topography can be described using the following terms: Elevation height of land above sea level. Relief difference in elevation between two points on the earth s surface. Gradient refers to the steepness of slopes. Geology the types of rocks and the history of those rocks. General appearance Is the description of landforms.

16 How are Landforms Built? The earth s surface is built of material that comes from beneath the crust, or it is formed by the movement of the earth s crust itself. The heat of the earth s interior creates convection currents in the mantle.

17 Important Terms Convection Currents: Movement of liquid caused by heat (ex. water bubbling as it boils)

18 Rift Valleys: formed when two plates pull apart and a valley is formed.

19 Mountains formed when two plates collide and one moves upward. Volcanic Mountains: Formed when magma moves towards the surface. It pushes up the crust but then cools and hardens as it nears the surface.

20 Plateau: a flat area between mountains. Plain: flat land under a lake or sea that is exposed when the water recedes

21 How Are Landforms Shaped? Canada s topography is the result of four forces: Mountain Building (building up force) Weathering the breakdown of rock (wearing down force)

22 Erosion wearing down due to running water, wind, waves and glaciers (wearing down force) Deposition depositing of eroded rock to make new landforms

23 Canada s Landform Regions Canada is so large that geographers divide it into regions to make it easier to study. A region is an area that is defined on the basis of the presence or absence of certain characteristics.

24 Geographers classify landform regions based on a combination of characteristics: Age of rock Type of rock Relief Gradient Process that has shaped the area

25 It is difficult to limit the number of Canadian landform regions. However, there is general agreement about the eight major regions shown in figure 2.11

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27 Canada s Landform Regions Canadian Shield Appalachian Mountains Western Cordillera Innuitian Mountains

28 Arctic Lowlands Interior Plains Great Lakes-St. Lawrence Lowlands Hudson Bay Lowlands

29 Foldable Assignment Instructions for folding: given in class One panel on each landform region Include all relevant information Location Age of rock Type of rock Relief Gradient Process that has shaped the area Last panel: Map of Canada with the landform regions outline with legend.

30 Climate and Weather The other major factor of Canada s geography that affects all Canadians and their sense of identity is our climate.

31 Weather atmospheric conditions on any given day Climate patterns of weather conditions over the long term. Meteorology the science of studying weather

32 Global Factors that influence Latitude Climate As distance from the Equator increases, it gets colder due to less direct sunlight.

33 Air Masses and Wind Maritime Air forms over water and is moist Continental Air forms over land and is dry Tropical Air warm Polar Air cool Arctic Air cold These can create different types of air masses. For example Maritime Tropical (mt) air is warm and moist.

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35 Ocean Currents can be warm or cold, making the surrounding area the same. Two currents that affect NL are: Labrador Current cold current from the north Gulf Stream Warm current from the Gulf of Mexico.

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37 Precipitation Terms: Dewpoint The Temperature where condensation occurs Front: The leading edge of an air mass

38 Precipitation Three Types Frontal Convectional Relief or Orographic

39 Frontal Precipitation: When two air masses meet, the warmer one will rise over the colder one. As it rises, the air will cool and condense, causing it to rain.

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41 Convectional Precipitation Occurs as a result of vertical movement within an air mass. Occurs over flat land on a hot summer day. The land will heat up quickly, the air will rise, cool, and precipitation will result

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43 Relief or Orographic Precipitation Occurs when moist air moves over a mountain barrier When moist air comes in off the ocean and it has to rise over a mountain it will cool, condense and rain will occur The opposite (leyward) side of the mountain is very dry (rain shadow)

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45 Regional Factors that affect Climate Altitude Bodies of water Mountain barriers

46 Altitude: As you go higher above sea level, the temperature decreases due to the thinning of the air

47 Closeness to Water Land heats up and cools off much faster than water. Land near the ocean will be cooler in the summer and milder in the winter. Inland locations (away from the ocean) will have cold winters and hot summers

48 Climate regions of Canada A climate region is an area that experiences similar weather conditions within its boundaries throughout a year. Developed in the early 1920 s by Wladimir Koppen, a German botanist and climatologist.

49 Koppen divided the world s climate into five types based on total annual temperatures and their precipitation, and their distribution throughout the year.

50 The Köppen system recognizes five major climatic types; each type is designated by a capital letter.

51 CLIMATE ZONE A Tropical Moist Climates: all months have average temperatures above 18 Celsius. (not found in Canada)

52 CLIMATE ZONE B Dry Climates: with deficient precipitation (evaporation and transpiration exceeds precipitation) during most of the year. Can be cool or warm

53 CLIMATE ZONE C Warm, moist climates Mild winters and warm, humid summers Parts of coastal British Columbia

54 CLIMATE ZONE D Cool, moist climates Most of Canada Wide range of average temperatures

55 Climate Zone E Polar Climates: Extremely cold winters and cool summers Very Dry