1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How to Use This Presentation To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show”, or simply press F5 on the top row of your keyboard. To advance to the next slide click the left mouse button once. From the Chapter screen you can click on any section to go directly to that section’s presentation. Blank or “missing” areas of a slide will remain hidden until the left mouse button is clicked. You may exit the slide show at any time by pressing the Esc key. How to Use This Presentation

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Transparencies Image and Math Focus Bank Bellringers Standardized Test Prep CNN Videos Visual Concepts Resources

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Weather Table of Contents Section 1 Water in the Air Section 2 Air Masses and Fronts Section 3 Severe Weather Section 4 Forecasting the Weather Chapter 16

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Bellringer Observe two glasses of water. One filled with ice water, and one filled with warm water. Why do water droplets form on the outside of the cold container? Where do the water beads come from? Why don’t the water beads form on the warm container? Write your answers in your science journal. Chapter 16

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Objectives Explain how water moves through the water cycle. Describe how relative humidity is affected by temperature and levels of water vapor. Describe the relationship between dew point and condensation. Chapter 16

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Objectives, continued List three types of cloud forms. Identify four kinds of precipitation. Chapter 16

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air The Water Cycle The condition of the atmosphere is affected by the amount of water in the air. Water in liquid, solid, and gaseous states is constantly being recycled through the water cycle. The water cycle is the continuous movement of water from sources on Earth’s surface into the air, onto and over land, into the ground, and back to the surface. Chapter 16

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Water Cycle 1 st – water on Earth’s surface is heated by the sun, changes from a liquid to a gas 2 nd – the gas rises into the atmosphere, condenses, and changes from a gas to a liquid 3 rd – water falls back to Earth as precipitation into bodies of water or is absorbed by Earth 4 th – excess runs off Chapter 16

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity Humidity is the amount of water vapor in the air. The air’s ability to hold water vapor changes as the temperature of the air changes. Chapter 16

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity As air temperatures increase, the amount of humidity increases because the air can hold more water vapor Once air holds all the water it can, it becomes saturated, this is 100% relative humidity Chapter 16

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity, continued Relative Humidity is the amount of water vapor in the air compared to the maximum amount of water vapor that the air can hold at a certain temperature. Given as a percentage Calculate the relative humidity by using the formula: Chapter 16 relative humidity (%)  actual water vapor content (g/m 3 ) saturation water vapor content (g/m 3 )

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity, continued As water vapor relative humidity As temperature relative humidity Chapter 16

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity, continued Measuring Relative Humidity A psychrometer is an instrument that is used to measure relative humidity. A psychrometer consists of two thermometers, one of which is a wet-bulb thermometer (covered with wet cloth), & dry bulb thermometer The difference in temperature readings between the thermometers indicates the amount of water vapor in the air (relative humidity). Chapter 16

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Humidity, continued

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Humidity, continued dry bulb measures air temp the damp cloth causes the bulb to cool as the water evaporates from the cloth if the air is dry, more water will evaporate, and the thermometer will have a lower temperature if the air is humid, less water will evaporate, and the thermometer will have a higher temperature Chapter 16

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Condensation Condensation is the process by which a gas, such as water vapor, becomes a liquid. to occur, the air must be saturated and cooling Dew Point The dew point is the temperature at which a gas condenses into a liquid.

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Clouds A cloud is a collection of small water droplets or ice crystals suspended in the air, which forms when the air is cooled and condensation occurs. Clouds are classified by form, and by altitude. if the air temp is above freezing, tiny water droplets form if the air temp is below freezing, ice crystals form 3 types – cirrus, stratus, and cumulus

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Clouds, continued nimbus – produce precipitation alto – middle altitudes cirro – higher altitudes Cumulus Clouds are puffy, white clouds that tend to have flat bottoms. fair weather, unless they become larger (thunderstorms) cumulonimbous, cirrocumulus, altocumulous, stratocumulous

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Clouds, continued Stratus Clouds are clouds that form in layers, block sun indicate rain or drizzle, light to heavy continuous rain nimbostratus, cirrostratus, altostratus, fog Fog is a stratus cloud formed near the ground Cirrus Clouds are thin, feathery, white clouds found at high altitudes. seen in fair weather, but indicate a change in weather

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Clouds, continued

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16 Precipitation Rain is the most common form of precipitation. produced when water droplets in a cloud become large enough to fall Snow Snow forms when temperatures are so cold that water vapor changes directly to a solid. Can be single ice crystals or snowflakes. Sleet Sleet forms when rain falls through a layer of freezing air. Hail are balls or lumps of ice that fall from cumulonimbous clouds

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Bellringer Think of as many different qualities of air as possible. Write your answers in your science journal. Chapter 16

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Objectives Identify the four kinds of air masses that influence weather in the United States. Describe the four major types of fronts. Explain how fronts cause weather changes. Explain how cyclones and anticyclones affect the weather. Chapter 16

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Air Masses Changes in weather are caused by the movement and interaction of air masses. An air mass is a large body of air where temperature and moisture content are constant throughout. Characterized by their moisture content & temperature, determined by the area over which the air mass forms m (maritime) – forms over water, wet c (continental) – forms over land, dry P (polar) – forms over polar regions, cool T (tropical) – forms over the tropics, warm Chapter 16

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Cold Air Masses Cold Air Masses Most of the cold winter weather in the United States is influenced by three polar air masses. ‘cP – forms over northern Canada, brings cold winter weather & cool, dry summer ‘mP – forms over North Pacific Ocean, bringing rain & snow in winter, cool & foggy in summer to Pacific coast forms over the North Atlantic Ocean, bringing cool, cloudy precipitation in winter, & cool foggy weather in summer to the New England coast Chapter 16

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Air Masses, continued Warm Air Masses Four warm air masses influence the weather in the United States. ‘cT – forms over the deserts of northern Mexico & southwestern US bringing clear, dry, hot summer weather ‘mT – brings hot, humid weather, thunderstorms, hurricanes in summer & mild, cloudy winters Chapter 16

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Fronts The area in which two types of air masses meet is called a front. 4 types : cold, warm, occluded, & stationary fronts Named according to which air mass is the “attacker” Cold Fronts A cold front forms where cold air moves under warm air, which is less dense, and pushes the warm air up. brings thunderstorms, heavy rain or snow followed by cooler weather Chapter 16

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Fronts Warm Fronts A warm front forms where warm air moves over cold, denser air. brings drizzly rain followed by clear warm weather Chapter 16

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Fronts, continued Occluded Front An occluded front forms when a warm air mass is caught between two colder air masses. coldest air mass moves under & pushes up the warm An occluded front has cool temperatures and large amounts of rain and snow. Stationary Front A stationary front forms when a cold air mass meets a warm air mass. neither has enough force to lift the warm over the cold A stationary front often brings many days of cloudy, wet weather. Chapter 16

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Air Pressure and Weather Air rises near low pressure areas as it rises, it cools and often condenses into clouds and precipitation An area of high pressure is a section of air that is sinking as the air sinks, it warms so it is able to hold more water Chapter 16

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Air Pressure and Weather Cyclones are areas of rising air that have lower pressure than the surrounding areas do. air direction converges (comes together) brings stormy weather Anticyclones are areas of sinking air that have high pressure. (sinking air is denser and pressure is higher) air direction diverges (moves apart) brings dry, clear weather Chapter 16

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Bellringer Write a one-paragraph description of a thunderstorm. Describe the weather conditions immediately before, during, and after the storm. How does the storm affect each of your senses? Record your response in your science journal. Chapter 16

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Objectives Describe how lightning forms. Describe the formation of thunderstorms, tornadoes, and hurricanes. Describe the characteristics of thunderstorms, tornadoes, and hurricanes. Explain how to stay safe during severe weather. Chapter 16

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Thunderstorms Lightning is an electric discharge that occurs between a positively charged area and a negatively charged area. Thunderstorms are very active electrically. Thunder is the sound that results from the rapid expansion of air along the lightning strike. Chapter 16

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Thunderstorms Produced by warm & moist air near the Earth’s surface, and an unstable atmosphere Atmospheres are unstable when surrounding air is colder than the rising warm air mass rises until it reaches its dew point, and condenses to form a cumulonimbus cloud which brings thunderstorms produces: high winds, flash floods, hail, tornadoes Flash floods are the leading cause of weather deaths Chapter 16

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Lightning The upper part of clouds carry a positive charge while the lower carries a negative charge Energy is released causing the air to expand rapidly and send out sound waves, thunder Lightning can cause deaths and forest fires Chapter 16

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Tornadoes A tornado is a small, spinning column of air that has high wind speeds and low central pressure and that touches the ground. A tornado starts out as a funnel cloud that develops in the bottom of a cumulonimbus cloud as spinning columns of air form into funnel clouds that touch the ground 75% of the world’s tornadoes occur in the US during spring and early summer when cold, dry air from Canada meets the warm moist air from the tropics Chapter 16

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Chapter 16 Tornadoes, continued

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Hurricanes How a Hurricane Forms A hurricane begins as a group of thunderstorms moving over tropical ocean waters. Winds traveling in two different directions meet and cause the storm to spin. Damage Caused by Hurricanes Hurricanes can cause a lot of damage when they move near or onto land. Wind speeds of most hurricanes range from 120 to 150 km/h. Chapter 16

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Hurricanes Most powerful storms on Earth because of the total energy involved, also known as typhoons and cyclones Most form between 5 and 20 degrees latitude over warm tropical oceans, start as several thunderstorms moving around an area of low pressure, Coriolis effect causes it to curve, the air rises as it rotates, thus it cools and condenses forming clouds Get their energy from condensation, and they continue to grow as long as they are over warm, moist air Chapter 16

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Hurricanes 3 Parts: eye eye wall – surrounds eye, strongest part, group of cumulonimbus clouds that produce the heavy rains and wind rain bands – beyond the eye wall, circle the hurricanes center, speed decreases as the distance from the eye wall increases Causes: flooding, storm surges, & property damage Chapter 16

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Chapter 16 Hurricanes, continued

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Severe Weather Safety Thunderstorm Safety Lightning is one of the most dangerous parts of a thunderstorm. If you are outside, stay away from trees, which can get struck down, and water. If you are in the open, crouch down. Tornado Safety If there is a tornado warning for your area, find shelter quickly. The best place to go is a basement or cellar. watch (tornado may happen) or warning (tornado seen) outdoors: lie in a large, open field or deep ditch Chapter 16

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Severe Weather Safety, continued Flood Safety The best thing to do during a flood is to find a high place to wait out the flood. stay out of floodwaters (even if shallow) Hurricane Safety If you live in an area where hurricanes strike, your family should have a disaster supply kit that includes enough water and food to last several days. Evacuate, if living near shore Board up windows Chapter 16

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Bellringer If you did not have the benefit of the weather forecast on the news, radio, or television, how would you forecast the weather? Record your answer in your science journal. Chapter 16

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Objectives Describe the different types of instruments used to take weather measurements. Explain how radar and weather satellites help meteorologists forecast the weather. Explain how to interpret a weather map. Chapter 16

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology Meteorologists collect data on atmospheric conditions, such as air pressure, humidity, precipitation, temperature, wind speed, & wind direction High in the Sky Weather balloons carry electronic equipment that can measure weather conditions as high as 30 km above Earth’s surface. Weather balloons which carry radio transmitters that send weather condition measurements to stations on the ground Chapter 16

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology Measuring Air Temperature and Pressure A tool used to measure air temperature is called a thermometer. An instrument used to measure air pressure is a barometer. Thermometers which measure air temperature using a liquid sealed in a glass tube; the liquid expands & moves up the tube as temperature increases Barometers which consist of a glass tube sealed at one end & placed in a container filled with mercury; as air pressure pushes on the mercury in the container, the mercury moves up the glass tube. The greater the air pressure, the higher the mercury rises. Chapter 16

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology, continued Measuring Wind Direction Wind direction can be measured by using a windsock or a wind vane. Windsocks are cone shaped cloth bags open at both ends allowing the wind to enter through the wide end & leave through the narrow end; thus, the wide end points to the wind Wind vanes, which are shaped like an arrow with a tail & are attached to a pole; wind pushes on the tail, spins the wind vane until the arrow points into the wind Chapter 16

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology, continued Measuring Wind Speed An instrument used to measure wind speed is called an anemometer. Anemometers consist of 3 – 4 cups connected by spokes to a pole. The wind pushes on the hollow sides of the cups causing them to rotate on the pole; the rotation sends a weak electric current that is measured and displayed on a dial. Gives wind speed. Chapter 16

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology, continued Radar and Satellites Radar is used to find the location, movement, and amount of precipitation. Weather satellites that orbit Earth provide images of weather systems. Radar (such a Doppler radar) is used to detect location, movement, amount, and form of precipitation Weather satellites provide images and conditions of weather systems at different altitudes Chapter 16

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather Maps Who Makes the Maps The National Weather Service produces weather maps based on information gathered from about 1,000 weather stations across the United States. Chapter 16

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology, continued Station model – small circles on weather maps that show the location of the weather station and are surrounded by symbols and data which represent the weather data Chapter 16

60. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather Maps, continued Reading a Weather Map Weather maps that you see on TV include lines called isobars. Isobars are lines that identify areas of equal, high, or low air pressure. Chapter 16

61. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Weather-Forecasting Technology, continued Isobars – lines on weather maps that connect points of equal pressure; if they form closed circles, they represent areas of high or low pressure Chapter 16

62. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Weather Concept Map Use the terms below to complete the concept map on the next slide. Chapter 16 water hail cumulus humidity weather air masses cirrus clouds fronts

63. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Concept Map Chapter 16

64. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Concept Map Chapter 16

65. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu End of Chapter 16 Show

66. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Read each of the passages. Then, answer the questions that follow each passage. Chapter 16 Standardized Test Preparation

67. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation Passage 1 In May 1997, a springtime tornado wreaked havoc on Jarrell, Texas. The Jarrell tornado was a powerful tornado, whose wind speeds were estimated at more than 410 km/h. The winds of the twister were so strong that they peeled the asphalt from paved roads, stripped fields of corn bare, and destroyed an entire neighborhood. Continued on the next slide

68. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation Passage 1, continued Some tornadoes, such as the one that struck the town of Jarrell, are classified as violent tornadoes. Only 2% of the tornadoes that occur in the United States are categorized as violent tornadoes. Despite the fact that these types of tornadoes do not occur often, 70% of all tornado-related deaths are a result of violent tornadoes.

69. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. In the passage, what does the word wreaked mean? A smelled B caused C prevented D removed

70. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. In the passage, what does the word wreaked mean? A smelled B caused C prevented D removed

71. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. Which of the following can be concluded from the passage? F Tornadoes often hit Jarrell, Texas. G Most tornadoes fall into the violent category. H The tornado that hit Jarrell was a rare type of tornado. I Tornadoes always happen during the spring.

72. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. Which of the following can be concluded from the passage? F Tornadoes often hit Jarrell, Texas. G Most tornadoes fall into the violent category. H The tornado that hit Jarrell was a rare type of tornado. I Tornadoes always happen during the spring.

73. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. Which of the following best describes a characteristic of violent tornadoes? A Violent tornadoes destroy paved roads. B Violent tornadoes damage crops. C Violent tornadoes damage homes. D Violent tornadoes have extremely strong winds.

74. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. Which of the following best describes a characteristic of violent tornadoes? A Violent tornadoes destroy paved roads. B Violent tornadoes damage crops. C Violent tornadoes damage homes. D Violent tornadoes have extremely strong winds.

75. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation Passage 2 Water evaporates into the air from Earth’s surface. This water returns to Earth’s surface as precipitation. Precipitation is water, in solid or liquid form, that falls from the air to Earth. The four major types of precipitation are rain, snow, sleet, and hail. The most common form of precipitation is rain. Continued on the next slide

76. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation Passage 2, continued A cloud produces rain when the cloud’s water drops become large enough to fall. A raindrop begins as a water droplet that is smaller than the period at the end of this sentence. Before a water drop falls as rain, it must become about 100 times this beginning size. Water drops get larger by joining with other water drops. When the water drops become too heavy, they fall as precipitation.

77. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. In this passage, what does precipitation mean? A acceleration B haste C water that falls from the atmosphere to Earth D separating a substance from a solution as a solid

78. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. In this passage, what does precipitation mean? A acceleration B haste C water that falls from the atmosphere to Earth D separating a substance from a solution as a solid

79. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. What is the main idea of the second paragraph? F Rain occurs when the water droplets in clouds become large enough to fall. G Raindrops are very small at first. H Water droplets join with other water droplets to become larger. I Rain is a form of precipitation.

80. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. What is the main idea of the second paragraph? F Rain occurs when the water droplets in clouds become large enough to fall. G Raindrops are very small at first. H Water droplets join with other water droplets to become larger. I Rain is a form of precipitation.

81. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. According to the passage, which step happens last in the formation of precipitation? A Water droplets join. B Water droplets fall to the ground. C Water droplets become heavy. D Water evaporates into the air.

82. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. According to the passage, which step happens last in the formation of precipitation? A Water droplets join. B Water droplets fall to the ground. C Water droplets become heavy. D Water evaporates into the air.

83. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics Use the diagram below to answer the question on the next slide. Chapter 16 Standardized Test Preparation

84. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. During an experiment, the setup shown in the diagram above is maintained for 72 h. Which of the following is the most likely outcome? A Beaker A will hold less water than beaker B will. B The amount of water in beaker A and beaker B will stay the same. C The amount of water in beaker A and beaker B will change by about the same amount. D Beaker B will hold less water than beaker A will. Chapter 16 Standardized Test Preparation

85. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. During an experiment, the setup shown in the diagram above is maintained for 72 h. Which of the following is the most likely outcome? A Beaker A will hold less water than beaker B will. B The amount of water in beaker A and beaker B will stay the same. C The amount of water in beaker A and beaker B will change by about the same amount. D Beaker B will hold less water than beaker A will. Chapter 16 Standardized Test Preparation

86. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation Interpreting Graphics Use the diagram below to answer the question on the next slide.

87. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. Look at the line graph. Which statement is consistent with the line graph? F The ability of air to hold moisture increases as temperature increases. G The ability of air to hold moisture decreases as temperature increases. H The ability of air to hold moisture decreases and then increases as temperature increases. I The ability of air to hold moisture stays the same regardless of temperature.

88. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. Look at the line graph. Which statement is consistent with the line graph? F The ability of air to hold moisture increases as temperature increases. G The ability of air to hold moisture decreases as temperature increases. H The ability of air to hold moisture decreases and then increases as temperature increases. I The ability of air to hold moisture stays the same regardless of temperature.

89. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Read each question and choose the best answer. Chapter 16 Standardized Test Preparation

90. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. The speed of light is 3.00  10 8 m/s. What is another way to express this measure? A 3,000,000,000 m/s B 300,000,000 m/s C 3,000,000 m/s D 300,000 m/s

91. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 1. The speed of light is 3.00  10 8 m/s. What is another way to express this measure? A 3,000,000,000 m/s B 300,000,000 m/s C 3,000,000 m/s D 300,000 m/s

92. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. A hurricane is moving 122 km/h. How long will it take to hit the coast, which is 549 km away? F 4.2 h G 4.5 h H 4.8 h I 5.2 h

93. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 2. A hurricane is moving 122 km/h. How long will it take to hit the coast, which is 549 km away? F 4.2 h G 4.5 h H 4.8 h I 5.2 h

94. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. A front is moving 15 km/h in an easterly direction. At that rate, how far will the front travel in 12 h? A 0.8 km B 1.25 km C 27 km D 180 km

95. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 3. A front is moving 15 km/h in an easterly direction. At that rate, how far will the front travel in 12 h? A 0.8 km B 1.25 km C 27 km D 180 km

96. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 4. On average, 2 out of every 100 tornadoes are classified as violent tornadoes. If there are 400 tornadoes in one year, which is the best prediction of the number of tornadoes that will be classified as violent tornadoes during that year? F 2 G 4 H 8 I 16

97. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 4. On average, 2 out of every 100 tornadoes are classified as violent tornadoes. If there are 400 tornadoes in one year, which is the best prediction of the number of tornadoes that will be classified as violent tornadoes during that year? F 2 G 4 H 8 I 16

98. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 5. The air temperature in the morning was 27°C. During the day, a front moved into the region and caused the temperature to drop to 18°C. By how many degrees did the temperature drop? A 1°C B 9°C C 11°C D 19°C

99. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation 5. The air temperature in the morning was 27°C. During the day, a front moved into the region and caused the temperature to drop to 18°C. By how many degrees did the temperature drop? A 1°C B 9°C C 11°C D 19°C

100. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16

101. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16

102. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Water in the Air Chapter 16

103. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

104. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Air Masses and Fronts Chapter 16

105. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Chapter 16

106. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Severe Weather Chapter 16

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108. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Forecasting the Weather Chapter 16

109. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation

110. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 16 Standardized Test Preparation

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