Living with Natural Hazards PDF

5 Living with natural hazards Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 1 Are we living in a hostile world? 1.1 What are the major natural hazards of the world?...

5 Living with natural hazards Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 1 Are we living in a hostile world? 1.1 What are the major natural hazards of the world?  Textbook pp. 3–5 1 What are natural hazards? Events caused by natural processes or forces that are out of human control Cause no harm or loss Cause harm and loss Cause great loss of life to humans to humans and severe property damage Natural events Natural hazards Natural disasters 2 Which of the following is/are natural hazard(s)? Tick ‘✓’ the correct answer(s). a A nuclear accident that caused 46 deaths. b A volcanic eruption in Tonga that resulted in four deaths. ✓ c A landslide in Hong Kong that damaged an outdoor bench. ✓ d An earthquake in the Atlantic Ocean that did not cause any deaths, injuries or property loss. 3 What are natural hazards a–f? Write their names in the blanks below and on p. 2. a Earthquake ( G ) b Drought ( M ) (Credit: D.W. Fisher-Freberg/Wikimedia (Credit: Galyna_Andrushko/Envato Elements) Commons) © Oxford University Press (China) Ltd 2022 1 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets c Flood ( M ) d Landslide ( G ) (Credit: bilanol/Envato Elements) (Credit: twenty20photos/Envato Elements) e Pest ( B ) f Typhoon ( M ) (Credit: CreativeNature_nl/Envato Elements) (Credit: Barry Bahler/Wikimedia Commons) 4 Classify natural hazards a–f by filling in the brackets with ‘G’ for geological hazards, ‘M’ for meteorological hazards or ‘B’ for biological hazards. 1.2 Where do different natural hazards occur?  Textbook pp. 6–8 1 Match the following natural hazards with the correct descriptions about their distribution patterns. (Note: One of the descriptions matches TWO natural hazards.) a They occur near rivers and coasts. (  ) b They are found mostly in the tropical regions. (  ) c They occur in a linear pattern around the Pacific Ocean. ( ,  ) © Oxford University Press (China) Ltd 2022 2 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 2 How can we describe the relief of a place? 2.1 How do we show relief on a map?  Textbook pp. 9–10 1 The relief of a place can be shown on a map in the following ways.  Colouring : Use colours to show the relief.  Contouring : Use contour lines to show the relief.  Conventional signs : Use signs to show the exact height of a place. 2 Complete the figure below to show how relief is shown. ( Highland / Lowland ) areas are usually shown in brown ( Highland / Lowland ) areas are usually shown in green 3 Refer to the map below. A contour line joins places with ( different / the same ) height(s) The vertical interval (V.I.) is the difference in height between two consecutive contour lines. It is 10 m on this map a Estimate the height of places X and Y respectively. X: 95 m Y: 110 m b What is the conventional sign showing the highest point? Trigonometric station c Name the conventional sign that shows the exact height of 108 m. Spot height © Oxford University Press (China) Ltd 2022 3 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 2.2 How do we show relief on a cross section?  Textbook pp. 11–15 1 a A cross section is a line graph showing the shape and the height of land. b Refer to the map below. In the space provided below, draw an annotated cross section of P–Q. 2 a Vertical exaggeration (V.E.) is the ratio between the vertical scale and the horizontal scale of the cross section. b Find the vertical exaggeration of the cross section above.  Vertical scale (refer to the cross section): 1:5,000/1 cm to 50 m  Horizontal scale (same as the map scale): 1:10,000/1 cm to 100 m Vertical exaggeration of the cross section Vertical scale = Horizontal scale 1:5,000 = 1:10,000 1 10,000 = × 5,000 1 =2 © Oxford University Press (China) Ltd 2022 4 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 2.3 How do we describe the steepness of a slope?  Textbook pp. 16–18 1 We can identify the steepness of a slope by:  studying the spacing of contour lines; or  calculating the slope gradient. A Study the spacing of contour lines 2 Complete the table below to show the steepness of the two slopes. Spacing of ( Widely spaced / Closely packed ) ( Widely spaced / Closely packed ) contour lines Type of slope ( Gentle slope / Steep slope ) ( Gentle slope / Steep slope ) B Calculate slope gradient 3 a Gradient is the ratio of the vertical distance (i.e. difference in height between two points) to the horizontal distance (i.e. distance between these two points on the ground). b Calculate the gradient of the following slopes. Vertical distance 13 m Gradient = Gradient = Horizontal distance 78 m 20 m = 1 in 6/1:6 = 20 m = 1 in 1/1:1 c Which slope has a larger ratio? Slope A–B d Which slope is steeper? Slope A–B © Oxford University Press (China) Ltd 2022 5 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 4 Find the gradient of Slope E–F on the map below. Show your calculations.  Vertical distance: 140 m – 60 m = 80 m  Horizontal distance: 120 m × 4.2 = 504 m Gradient of Slope E–F 80 m = 504 m = 1 in 6.3/1:6.3 2.4 What relief features can we find on contour maps?  Textbook pp. 19–22 Complete the table on pp. 6–8 to show the relief features and their characteristics on maps. Relief feature Characteristic on maps 1 Convex slope Contour lines are ( widely spaced / closely packed ) at the upper part of the slope and ( widely spaced / closely packed ) at the lower part of the slope 2 Concave slope Contour lines are ( widely spaced / closely packed ) at the upper part of the slope and ( widely spaced / closely packed ) at the lower part of the slope © Oxford University Press (China) Ltd 2022 6 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets Relief feature Characteristic on maps 3 Valley Contour lines bend towards ( higher / lower ) ground 4 Spur Contour lines bend towards ( higher / lower ) ground 5 Cliff Contour lines are very ( widely spaced / closely packed ) across a short distance 6 Ridge Contour lines are elongated with a number of peaks 7 Basin Contour map shows a piece of flat land surrounded by ( higher / lower ) ground, which generally rises over 1,000 m above it © Oxford University Press (China) Ltd 2022 7 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets Relief feature Characteristic on maps 8 Plateau Contour map shows a large flat area at ( higher / lower ) ground, which is generally over 1,000 m, surrounded by downward-sloping land 9 Conical hill Contour lines are circular in shape, with the innermost contour line forming a small circle 10 Round-topped hill Contour lines are circular in shape, with the innermost contour line forming a large circle 11 Flat-topped hill The pattern of contour lines is similar to that of a plateau, but the height is much lower and the area of flat land at the hilltop is much smaller © Oxford University Press (China) Ltd 2022 8 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 2.5 How can we describe the relief of Hong Kong?  Textbook pp. 23–4 Refer to the map below. Few natural lowland areas, Hilly relief with much including river valleys and coastal plains of the land higher than 200 m Lowland areas on the two sides of Plenty of Long and ( regular / Victoria Harbour and offshore irregular ) coastline result some new towns (e.g. Sha Tin) are islands in many bays created by reclamation 1 Complete the map above to describe the relief of Hong Kong. 2 Name hills/peaks A–C. A Lantau Peak B Tai Mo Shan C Lion Rock © Oxford University Press (China) Ltd 2022 9 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 3 What are the causes and effects of landslides? 3.1 What are landslides?  Textbook p. 27 1 Landslides occur when a mass of soils and rock of all sizes moves down a slope ( slowly / rapidly ) due to gravity. 2 Landslides occur on both natural terrain and man-made slopes. 3.2 How do landslides affect us?  Textbook p. 28 Complete the figure below to show how landslides affect us. Landslides (Credit: Indonesian National Board for Disaster Management/Wikimedia Commons) Bury buildings Damage infrastructure Block roads such as water pipes, gas pipes and stop and power lines traffic Cause injuries Cut off the supply of Disrupt people’s and deaths these services daily lives © Oxford University Press (China) Ltd 2022 10 Junior Secondary Exploring Geography (Third Edition) 5 Living with natural hazards Revision worksheets 3.3 Why do slopes collapse?  Textbook p. 29 1 Complete the figure below to show the forces that control slope stability.  Driving force drives movement. It pulls slope materials downhill under the force of gravity. It is mainly controlled by: a Slope gradient : b Weight of slope materials: The larger it is, the The heavier the slope materials, greater the the greater the tendency for driving force them to fall down  Resisting force resists movement down the slope. It prevents slope materials from sliding down. It is affected by: a Cohesion b Force of friction : of slope materials: The resistance to motion The force that between soil causes soil grains to grains stick together 2 When will a slope become unstable and collapse? Tick ‘✓’ the correct box.  >  