2nd Grade. Wind, Water and Land.

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2 2nd Grade Wind, Water and Land

3 Wind, Water and Land What is Wind? Wind Erosion Preventing Wind Erosion Water Erosion Sudden Water Erosion Preventing Water Erosion Landforms as Homes 3

4 What is Wind? Return to Table of Contents 4

5 What Am I? I saw you toss the kites on high And blow the birds about the sky; And all around I heard you pass, Like ladies' skirts across the grass I saw the different things you did, But always you yourself you hid. I felt you push, I heard you call, I could not see yourself at all O you that are so strong and cold, O blower, are you young or old? Are you a beast of field and tree, Or just a stronger child than me? 5

6 What is wind? You can't see the air and you can't see the wind, but you can tell its there. You feel your hair blowing, clouds traveling across the sky and leaves moving in a tree. Wind is moving air. Source: fplsafetyworld.com 6

7 The Power of Wind Suppose that you are at the beach and you build a sandcastle. If it suddenly became very windy, what would happen to your castle? In your groups, think of 3 other ways that wind affects you. 7

8 Effect of Temperature Review Remember back to when you learned about how matter can change state by changing the temperature. How do particles change as they heat up? Particles move faster and spread apart. How do particles change as they cool down? Particles move slower and get close together. 8

9 Temperature and Air These same ideas hold true for the particles in the air. When air heats up, the molecules spread out. When air cools down, the molecules get close together. What type of air do you think is heavier, warm or cool? 9

10 If you fill a shoebox with hot air, it would look something like this: If you fill the same shoebox with cold air, it would look something like this: Temperature and Air In the same space, there are less molecules of hot air than there are of cold air. This means that cold air is heavier than hot air. 10

11 How is Wind Created? Rays from the sun heat up Earth's surface. However, different types of surfaces heat up faster than others. The air over land heats up quickly. The air over water heats up slowly. Earth's Surface 11

12 The air over land is light and rises. How is Wind Created? It is replaced by the heavier cold air over the water. You feel this as the wind. 12

13 1 What is wind? A Hot air B Moving air Answer C Cold air 13

14 2 The Sun up Earth's surface and causes the air above it to move upwards. A Pushes B Moves Answer C Cools D Heats 14

15 3 Hot air is heavier than cool air. True False Answer 15

16 4 Which are examples of how you can tell there is wind? Choose all that apply. A Watch a cloud move across the sky. B See a tree blowing in the wind. C Hear it blowing. Answer D Feel it on your skin. 16

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22 Wind Lab In this lab you will investigate what wind is and how you can measure it by building an anemometer. 22

23 Wind Erosion Return to Table of Contents 23

24 The Power of Wind The Arches are a rock formation found in Utah's Moab Desert. This amazing structure was formed, in part, by the power of wind. How does wind create landforms? Can you think of other places you have seen structures affected by wind? 24

25 Wind Causes Change Wherever there is wind it is working to change the landscape. Wind causes erosion, the carrying and moving of materials that change the landscape. 25

26 Wind Erosion Wind erosion happens on loose sand and solid rock. How do you think erosion can happen in each picture? 26

27 Wind Erosion Wind can pick up loose sand and carry it away to new locations. 27

28 Wind Erosion On hard surfaces, the sand already carried by the wind grinds against the surfaces. This breaks down the rock into smaller pieces that are carried away by the wind. 28

29 Wind Creates Landforms Wind erosion creates many unique landforms. As the wind carries particles of sand and soil it blasts them against the surface of rocks, slowly grinding them down. 29

30 Wind Erosion Look at the pictures below. In what type of environment do you think wind erosion is most common? Dry environments with little vegetation. 30

31 Sandstorms Sandstorms are caused when a strong wind blows over loose sand or soil. The sandstorm picks up the loose material and carries it away. 31

32 Sandstorms A sandstorm can carry sand from the Sahara desert in Africa all the way to the Caribbean! 32

33 Dunes Dunes form when sand carried by wind hits an obstacle that causes the sand to be deposited. Sand begins to pile up causing more sand to be deposited. Sandstorms can move entire dunes! 33

34 Hurricanes Hurricanes are huge storms that form over the ocean. They can create winds up to 200 miles per hour. These strong winds can cause erosion as well as damage to buildings, cars and trees. 34

35 Tornados Tornados are powerful columns of rotating air that form over land and are capable of producing winds up to 300 miles per hour. When tornados touchdown they can reshape the landscape and can destroy anything in their path. 35

36 5 Sandstorms are. A Strong winds that pick up loose soil and sand B Things that deflect wind and reduce soil erosion C When sand is piled up Answer D Huge storms that form over the ocean 36

37 6 What is erosion? A The movement of materials B The process of breaking things down C The heating of the earth's surface Answer D A way to prevent flooding 37

38 7 A powerful rotating column of air that can reach speeds up to 300 mile per hour is a. A Sandstorm B Hurricane C Dune Answer D Tornado 38

39 8 Which landscape would be most impacted by wind erosion? A B A Picture A B Picture B C Both A & B Answer 39

40 9 Hurricanes form over the ocean and tornados form over. A Seas B The land C A long period of time Answer D Oceans 40

41 10 Wind erosion happens more often when there is. A lots of vegetation. B very little loose sand. C very little vegetation and lots of sand. Answer 41

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47 Preventing Wind Erosion Return to Table of Contents 47

48 Negative Impacts of Wind Erosion Although wind erosion can create interesting landforms, it also has negative impacts on the environment. It destroys crops. How? It destroys habitats. This barrier island was cut in half by a hurricane. 48

49 Preventing Wind Erosion Planting vegetation can help to prevent wind erosion. Look at this picture and describe how you think the plant can help prevent erosion. The answer is under the picture. The roots of vegetation hold onto soil particles and stop them from being carried away. 49

50 Preventing Wind Erosion Windbreaks are rows of trees, bushes, fences, or other structures that help prevent wind from carrying soil away. Trees and other plants provide a natural windbreak. 50

51 How Windbreaks Work Natural or manmade windbreaks work by blocking the wind to protect the soil. As the air moves upward it loses speed. The wind is then carried over the protected area instead of through it. 51

52 Vegetation Protects Habitats Sea oats have been planted in these sand dunes at the beach. How would this help to protect the coastal area from wind erosion? 52

53 Windbreaks Improve Farming Can you locate the natural windbreak in this picture. How would the windbreak improve the crop yield of this farm? 53

54 11 Which formation could be formed by wind erosion A B C D Answer 54

55 12 Wind erosion never has negative impacts on the land. True False Answer 55

56 13 What is a windbreak? A Something like a fence or tree row that provides protection from the wind B A mound of sand formed by the wind C Slow moving air Answer D A strong storm that forms over the ocean 56

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60 Water Erosion Return to Table of Contents 60

61 The Power of Water This is a picture of the Colorado River winding through the Grand Canyon. Talk with your group about how water can work to create landforms such as this. Click here to watch a video about the Grand Canyon. 61

62 Water Erosion Like wind, water can also erode land and shape landforms. As water flows along a rock it breaks away tiny pieces of the rock and carries it away. This is called water erosion. 62

63 Deltas Water erosion over a long period of time creates different types of landforms. Rivers flow into big bodies of water like lakes and oceans. Deltas are small pieces of land that form when river water leaves rocks and sand behind on the way to lakes and oceans. 63

64 Canyons Water erosion over a long period of time creates different types of landforms. Canyons form when water carves away rock. 64

65 Valleys Valleys are an area of low land surrounded by hills or mountains. They are also formed by erosion and the gradual wearing away of the land by running water. Rivers are often found in the bottom of valleys. 65

66 Waterfalls occur at places where water suddenly plunges downward off a cliff. Waterfalls form when streams flow over areas of hard and soft rocks. The water erodes away the soft rocks until an area of harder rocks is reached. The result is a cascade of water. Waterfalls 66

67 14 Which picture is an example of a canyon? A C B D Answer 67

68 15 Deltas are formed when. A Rivers deposit silt, soil and rocks at the rivers mouth B Rivers change course C Rivers flow beteen two mountains Answer D Wind piles up sand 68

69 16 What type of erosion caused this landform? A Wind B Rocks C Water D Sun Answer 69

70 17 Valleys and waterfalls are formed by. A Wind Erosion B Sandstorms C Flowing water Answer D Tornados 70

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74 Erosion Activity How can wind and water cause erosion? Follow the directions to find out! 74

75 Sudden Water Erosion Return to Table of Contents 75

76 Sudden Erosion Look at these pictures. What do you think happened to cause this destruction? 76

77 Sudden Erosion While some types of water erosion can take thousands or millions of years, water can cause sudden and rapid erosion, too. Forces such as heavy rains, hurricanes and flash floods can change the landscapes dramatically without much warning. 77

78 Hurricanes Waves and the heavy rain from a hurricane cause coastal erosion. 78

79 Flash Flooding Flash flooding is sudden flooding that occurs when floodwaters rise rapidly due to intense rain. They often occur without warning and can dramatically change the shape of the land. 79

80 Waves Ocean currents, tides and waves are continuously shaping and changing the coastal landscapes. Waves can change a shoreline over many years, or dramatically change the landscape quickly. 80

81 18 Water erosion occurs when water move particles away from their source. True False Answer 81

82 19 Hurricanes cause erosion by. Choose all that apply. A rain B storm surge C wind Answer D waves 82

83 20 What causes flash flooding? A Glaciers B Atmosphere Answer C Strong winds D Heavy Rains 83

84 21 Waves are constantly changing the shoreline. True False Answer 84

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89 Preventing Water Erosion Return to Table of Contents 89

90 Negative Impacts of Water Erosion Just like wind erosion, water erosion has several negative impacts. It destroys habitats as well as human communities. It carries away soil and nutrients for farming. 90

91 Terracing To prevent damage by water erosion, farmers use a technique called terracing. How do you think shaping the land in this way would help to prevent water erosion? 91

92 Terracing Terracing creates ridges on a steep slope. This reduces erosion by decreasing the steepness of the slope. Water can be channeled off the slope instead of it running down the slope and causing erosion. 92

93 Coastal Erosion When erosion occurs along the coast, it is called coastal erosion. Look at the map. What areas have the highest rates of erosion? 93

94 Coastal Erosion Coastal erosion is a natural process. Coastlines have been changing throughout time. Humans have built right next to the coast, and it is now a problem for us. 94

95 Coastal Erosion To protect human communities, we attempt several different techniques to reduce coastal erosion. Hard structures Beach nourishment Changing human behavior Important: None of these techniques can stop coastal erosion. They simply try to reduce it. 95

96 Hard Structures Hard structures refer to structures that are built into a waterway to prevent water erosion. This seawall is a wall built along the coast that protects the area from erosion by strong waves and storms. 96

97 Hard Structures This jetty is a wall that extends into the ocean, reducing water erosion by waves and currents. Breakwaters are wall built parallel to the shore (in the same direction as the shore) to reduce water erosion by waves and currents. 97

98 Beach Nourishment Beach nourishment includes ways to reduce wind and water erosion other than by building structures. What changes were made to this beach? Source: nagsheadnc.gov 98

99 Beach Nourishment During beach nourishment, sand is added to the beach and vegetation is planted along the coastline. This tube is pumping new sand onto this beach. 99

100 Changing Human Behavior Since coastal erosion cannot be stopped, the only way to prevent damage to human commities is to implement land use limits. In your group, come up with some ways that humans can change their behavior to prevent being affected by coastal erosion. Click the box for a few examples. Laws that prevent humans from building right next to the coast. Designating coastal areas as park land. 100

101 Changing Human Behavior: Discussion Why do you think coastal governments do not want to change regulations to prevent erosion? 101

102 22 What type of erosion technique would most likely be used by a farmer? A breakwater B beach nourishment C terracing Answer D jetty 102

103 23 Coastal erosion is an unnatural process. True False Answer 103

104 24 This wall has been built along the coast to protect the community from water erosion from waves. What type of structure is this? A Jetty B Seawall C Breakwater Answer D Dam 104

105 25 Coastal erosion cannot be stopped, only reduced. True False Answer 105

106 26 Planting sea oats along sand dunes would be considered what type of erosion technique? A Hard structure B Beach nourishment C Changing human behavior Answer 106

107 27 These walls have been built parallel to the shore to try to reduce water erosion. What type of structure is this? (Choose all that apply.) A Hard structure B Beach nourishment C Jetty Answer D Breakwater Source: Virginia Institute of Marine Science 107

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110 Coastal Erosion Activity Model coastal erosion and see how it changes the shape of beaches. 110

111 Landforms as Homes Return to Table of Contents 111

112 Landforms as Homes As wind and water cause erosion and create new landforms, they also provide homes for living things. Many plants and animals call different land forms their homes. 112

113 Landforms as Homes Look at the landforms below. What types of animals might live there? What types of conditions would animals need to be able to survive in each picture? Source: National Geographic Source: National Geographic 113

114 Animals have special characteristics that make certain landforms good homes for them. Bighorn Sheep can climb steep canyon walls. Pinion pines can shoot their roots into the cracks in the canyon wall rocks. Vultures can soar high above the canyon looking for an easy meal. Canyons 114

115 Deltas Shallow waters in deltas make good homes for many types of fish, birds, plants and animals because they are warm, have good soil, for plants, and easily trap food particles. 115

116 Deserts and Dunes Some plants and animals can survive in places without much water. How can a cactus survive in the desert? Think about what it looks like, not just that it can survive without water. A cactus can live in the desert because it doesn't need very much water, has prickly thorns to keep animals from eating it, and does not blow over easily in the wind. Move the picture for the answer 116

117 28 What type of landform would this animal most likely make a home? A Desert B River delta C Cave Answer D Canyon 117

118 29 Animals use natural landforms created by wind and water erosion as homes. True False Answer 118

119 30 What type of landform would this animal most likely make a home? A Canyon B River delta C Cave. Answer D Sand dunes 119

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