Weather Effects KEY CONCEPTS AND PROCESS SKILLS KEY VOCABULARY ACTIVITY OVERVIEW O V E R I T TA L K I N G E-1

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1 Weather Effects to 1 50-minute session ACTIVITY OVERVIEW TA L K I N G I T O V E R A fictional story focuses on how weather affects people s plans and activities. Students discuss their ideas about weather and jobs that are affected by severe weather. They are introduced to four kinds of careers related to the science of weather. They then examine maps that show the relative level of risk of different weather disasters and discuss the likelihood of those weather events occurring locally. KEY CONCEPTS AND PROCESS SKILLS (with correlation to NSE 5 8 Content Standards) 1. Weather is the outdoor conditions (such as temperature, precipitation, cloud cover, etc.) at a particular time and place. (EarthSci: 2) 2. Scientists use common units of measurement to collect data. This system is known as the metric or international system (SI). (Inquiry: 1) 3. Weather-related hazards such as hurricanes, floods, and tornadoes pose risks to human life and property. (Perspectives: 4) 4. The level of risk of a weather-related disaster is different for different regions. (Perspectives: 4) 5. Meteorologists, atmospheric scientists, climatologists, and hydrologists study different aspects of earth s weather and atmosphere. Society relies on the information provided by such scientists. (History: 1) KEY VOCABULARY risk weather (formally defined in Activity 53, Weather and Climate ) E-1

2 Activity 50 Weather Effects MATERIALS AND ADVANCE PREPARATION For each student 1 Student Sheet 50.1, Intra-act Discussion: Weather Effects 1 Student Sheet 50.2, Scientific Careers in Weather *Not supplied in kit Teacher s Note: Various activities in this unit refer to weather disasters, such as floods and hurricanes, that routinely result in the loss of life and property. Please be aware that some students and their families may have experienced such devastation firsthand and may be sensitive to these topics. You might adapt activities and questions to anticipate such issues. TEACHING SUMMARY Getting Started 1. Students brainstorm a list of words used to describe weather. Doing the Activity 2. (LITERACY) Students read and discuss a weather-related story. Follow-Up 3. Discuss the concept of risk. 4. The class revises the weather-word list, and each student selects a weather-related career. E-2

3 Weather Effects Activity 50 BACKGROUND INFORMATION Floods Floods can happen at any time, almost anywhere in the United States. This is because floods can result from a single heavy rainfall, days of moderate levels of rain, melting of snow and ice, the breaking of a dam or levee, and even ocean waves arriving onshore. Large-scale flooding often occurs during seasons with exceptionally high rainfall, or springtimes that produce large snowmelt. In many places that are susceptible to annual flooding, dams and levees have been built along the waterways to prevent such flooding. Floods that result from short periods (typically several hours) of extremely heavy rain are known as flash floods and are less predictable than other floods. Flash floods occur when heavy rainfall creates local flooding as large amounts of water overwhelm creeks and rivers. One common place for flash floods is the desert. Deserts do not receive much rain, and do not absorb water quickly. When a heavy downpour occurs, streams can quickly overflow, resulting in flash floods. Hurricanes A hurricane is a severe tropical storm, and those that hit the United States typically originate in the Caribbean Sea, the Gulf of Mexico, or the Atlantic Ocean. In other parts of the world, hurricanes are also known as tropical cyclones and typhoons. Hurricanes form in areas of warm tropical water where there is moisture and an absence of strong winds, and they can produce high winds, heavy rains, and flooding. In the United States, hurricane season runs from June through November, when water temperatures are generally higher, providing the energy for those storms. By definition, hurricanes have winds of at least 119 kilometers per hour (km/hr) equal to 74 miles per hour (mi/hr) that swirl around a calm center, known as the eye. The eye is usually about kilometers (20 30 miles) in diameter, while the entire diameter of the hurricane may extend to 600 km (400 mi).over the open ocean, a hurricane can last for more than two weeks. Some strike the coast of the eastern United States and then come inland, losing energy as they continue over land. The Saffir-Simpson Hurricane Scale classifies hurricanes into categories based on their wind speed (and potential to cause damage), from a category one (less than 150 km/hr, or 95 mi/hr) to a category five (more than 250 km/hr, or 155 mi/hr). Hurricanes are low-pressure events. Along ocean fronts, this low pressure can create a storm surge that brings large amounts of ocean water onshore, with waves reaching up to several meters high. Storm surges cause significant damage during strong hurricanes, in part due to the large amount of water and resulting flooding. If a storm surge coincides with a low tide, the damage is lessened; but when combined with a high tide, a surge can be extremely destructive. Hurricanes are given names in alphabetical order (excluding letters Q, U, and Z) with the name of the first one each year starting with the letter A. The World Meteorological Organization rotates six lists of names and reuses names every sixth year. The name of a particularly deadly or costly hurricane, however, is retired from the lists, and a new name is selected to take its place. E-3

4 Activity 50 Weather Effects Tornadoes A tornado is a violently rotating column of air that is in contact with both the ground and a cloud layer. It is usually seen as a funnel cloud and can have winds as strong as 500 km/hr (300 mi/hr). Tornadoes can last from several seconds to longer than than an hour, though most die out in less than 10 minutes. Meteorologists use the Fujita- Pearson scale to rate the severity of tornadoes based on resulting damage and assumed wind speeds, from F-0 (less than 120 km/hr, or 73 mi/hr) to F-5 ( km/hr, or mi/hr). Tornado damage tends to occur in a narrow swath (for example, two km wide) running a long distance (up to 80 km, for example). A tornado s high winds and low pressure (relative to normal atmospheric pressure) can cause the windows of buildings to blow outward. Compared to any other country, the United States experiences the greatest number of tornadoes. About 1,000 tornadoes are reported here per year on average, resulting in approximately 80 deaths and more than 1,500 injuries. Many of these tornadoes occur in Tornado Alley, a region of the central United States that includes Texas, Oklahoma, Kansas, Nebraska, and South Dakota. Tornadoes can form at any time of the year, but are most common in the United States between March and August. REFERENCES U.S. Geological Survey. Geographic Distribution of Major Hazards in the U.S. (website). U.S. Department of the Interior. Retrieved January 2005 from E-4

5 Weather Effects Activity 50 TEACHING SUGGESTIONS GETTING STARTED 1. Students brainstorm a list of words used to describe weather. Tell students that they have one minute to brainstorm a list of words used to describe weather. If students are having difficulty with the task or if your student population needs additional assistance, you may want to have students work in small groups. Students are likely to come up with lots of qualitative words, such as sunny, hot, rainy, and cloudy. Use their responses to create a class list of weatherrelated words. Inform students that they will revisit the list at the end of the activity to see if they can add more words. DOING THE ACTIVITY 2. (LITERACY) Students read and discuss a weather-related story. Decide how you would like students to read the story. You might assign each group of four students to read the story aloud, with each student reading one of the four roles. Or, you could have one group role-play the four characters for the class. After students have completed the reading, pass out Student Sheet 50.1, Intra-act Discussion: Weather Effects and Student Sheet 50.2, Scientific Careers in Weather. Intra-act is a literacy strategy intended to facilitate discussion and help students synthesize concepts. Statement 3 on Student Sheet 50.1 also initiates the idea that different regions have different levels of risk for various weather hazards. Students will use Student Sheet 50.2, throughout the unit as a checklist of the knowledge and skills related to the science of weather. Have students evaluate each statement on Student Sheet 50.1 independently and record whether they agree or disagree by circling Agree or Disagree next to each statement in the column titled Me. Students should then predict the responses of the other three members of their group. Group members then take turns revealing how each responded to the four statements and why. As each member shares his or her opinions, the other group members should compare their predictions to the actual responses. Sample responses to the statements are shown below. Sample Responses to Student Sheet 50.1, Intra-act Discussion: Weather Effects 1. People usually change their plans based on weather forecasts. Some students may agree with the statement, especially since the story contained examples of such changes (flight delayed, ship changing course, and delivery trucks delayed). They may provide other examples of plans that have been changed, including school closings during severe weather and cancellations of outdoor events. Students who disagree might say that many plans are not weather-dependent or must be carried out regardless of the possible inconvenience or hazards. 2. Every job is affected by weather. Some students may agree with this statement because weather can interfere with how people get to and from work. The reading also mentions an airline pilot and a truck driver as examples of people in jobs that are directly affected by weather. Students who disagree might cite jobs that are less weather-dependent, such as jobs in office buildings or jobs in parts of the country that routinely have good weather, such as the southwestern United States. 3. Heavy snowfall within a short period of time is one of the most dangerous weather conditions. Students are likely to agree or disagree based on their own experiences. In some parts of the United States, blizzards are the most common severe weather phenomena. Students who have experienced dangerous winter driving conditions, had to walk outdoors in freezing temperatures, lost electricity due to snowstorms or observed school and business closures due to heavy snow might consider blizzards to be one of E-5

6 Activity 50 Weather Effects the most dangerous types of weather. In parts of the country that receive little or no snow over the course of a typical year, students might be familiar with other types of severe weather, such as flooding or hurricanes; they would more likely to disagree with the statement. 4. The best way to describe weather is to provide exact measurements, such as 32 Celsius. Some students will disagree, saying exact measurements are meaningless unless a person has an understanding of the units used (for example, is 32 C hot or cold?). Other students agree with the statement because precise measurements can communicate more information than a qualitative descriptions, such as it s hot. A few students may point out that the best way to describe the weather depends on the person doing the describing and that person s intended purpose. FOLLOW-UP 3. Discuss the concept of risk. The Analysis Questions are intended to guide group and class discussion. Use Question 3 to discuss the concept of risk. The risk maps produced by the U.S. Geological Survey reflect the number of each type of event that has occurred in each region over time. The frequency of past events is used to predict the likelihood of future events. Ask, Do you think this is a good way to predict risk? Why or why not? A strength of this approach is that it identifies events that follow historical patterns (for example, hurricanes that have formed in the Atlantic have made landfall in Maine three times since 1950). A weakness is that it is unlikely to predict unusual events or those that occur infrequently. Teacher s Note: Flooding associated with hurricanes, such as the flooding that occurred as a result of Hurricane Katrina in 2005, is reflected in the Hurricane Risk map (and not the Flood Risk map) since the flooding was a result of the hurricane and its associated storm surge. Many students will want to discuss their own experiences. Questions 1 and 4 are intended to provide them that opportunity. If they raise questions about your local area, tell them that they will have a chance to gather more information in the next two activities. 4. The class revises the weather-word list, and each student selects a weather-related career. Ask students to see if they can come up with additional words related to weather. This time they are more likely to provide quantitative words, particularly units of measurement such as Celsius or kilometers per hour. Ask the class, How did the activity help you think of new words associated with weather? What did the activity make you think of that you didn t think of before? Students are likely to note that the activity jogged their memory and made them think of more types of weather and weather conditions. Review the weather-related careers listed on Student Sheet Each career has an associated set of skills. Over the course of the unit, students will learn more about each of these careers and will demonstrate knowledge and/or mastery of these skills. Ask students to select one of these scientific careers to focus on for the course of the unit. Ideally, one student in each group of four would select one of the four careers. Throughout the unit, students will work to master the list of skills associated with their chosen scientific career. You might consider signing off on a skill once students have demonstrated mastery. Or, you can encourage students to monitor their own progress by checking off the skills they are confident they have mastered. Consider adjusting this sheet to meet the needs of your students. For some, you may require them to demonstrate five of the eight skills by the end of the unit. For others, you may challenge them to master the skills of more than one scientific career. E-6

7 Weather Effects Activity 50 SUGGESTED ANSWERS TO QUESTIONS 1. How does weather affect your daily life? Provide at least two examples of situations when weather caused you to change your plans. Sample responses include situations such as: deciding what to wear; how to get to school (walking, bus, car); arriving at school on time; participating in after-school activities, especially those that occur outdoors; where to go on vacation; and what to do with friends during free time. 2. Use information from the activity to complete the following table. Units Used to Measure Weather Data Temperature Metric Units degrees Celsius English Units degrees Fahrenheit Rainfall centimeters inches Snowfall centimeters inches Wind Speed kilometers per hour miles per hour Teacher s Note: Differences between the metric and English systems of measurement were introduced in Unit A of Issues and Earth Science, and students are expected to be familiar with the abbreviations of the units referred to in this activity (for example, cm for centimeters). If necessary, review the abbreviations for the units asked for in Analysis Question Locate your state on the three risk maps shown on the next page [in the student book.] These maps, produced by the U.S. Geological Survey, are based on the numbers of hurricanes, floods, and tornadoes that have occurred in each region. Note: These maps do not include the states of Alaska and Hawaii. What is the level of risk of: a. Hurricanes in your state? Answers will vary based on state. States at the highest level of risk for hurricanes include Florida, Georgia, South Carolina, and North Carolina. b. Floods in your state? Answers will vary based on state. States at the highest level of risk for floods include Washington, California, North Dakota, and Minnesota. c. Tornadoes in your state? Answers will vary based on state. States at the highest level of risk for tornadoes include Texas, Oklahoma, Kansas, Nebraska, Iowa, Indiana, Arkansas, Mississippi, Alabama, Georgia, Pennsylvania, and New York. 4. Reflection: What is the worst weather you have experienced? How did it affect you? Describe your experience. Answers will vary based on students experiences. Allow students to share their experiences with the class. E-7

8 Name Date Intra-act Discussion: Weather Effects 2006 The Regents of the University of California Names Me 1. People usually change their plans based on weather forecasts. Agree/Disagree Agree/Disagree Agree/Disagree Agree/Disagree + or + or + or 2. Every job is affected by weather. Agree/Disagree Agree/Disagree Agree/Disagree Agree/Disagree + or + or + or 3. Heavy snowfall within a short period of time is one of the most dangerous weather conditions. Agree/Disagree Agree/Disagree Agree/Disagree Agree/Disagree + or + or + or 4. The best way to describe weather is to provide exact measurements, such as 32 degrees Celsius. Agree/Disagree Agree/Disagree Agree/Disagree Agree/Disagree + or + or + or + : Predictions were correct. : Predictions were incorrect. Number of correct predictions: /12 Issues and Earth Science Student Sheet 50.1 E-9

9 Name Date Scientific Careers in Weather Meteorologist A scientist who studies Hydrologist A scientist who studies Identify the metric units used to measure wind speed Calculate the mean and median wind speed for a five-day period Graph and analyze wind speed for a twelvemonth period Describe cold and warm fronts and the weather associated with each Conduct a survey to determine the most common type(s) of severe weather in your area over the past 30 years Design an instrument to measure wind direction or speed Predict the weather based on current weather maps Calculate the change in air temperature for a growing city over a period of time Identify the metric units used to measure precipitation Calculate the mean and median precipitation for a five-day period Graph and analyze precipitation data for a 12- month period Describe the amount of the earth's surface covered by water Investigate how well different solids dissolve in water Investigate how well water flows through different earth materials Describe at least three different ways in which water changes from one state to another Evaluate the impact of the population of a city on the city s water supply Climatologist A scientist who studies Atmospheric Scientist A scientist who studies 2006 The Regents of the University of California Identify the metric units used to measure temperature Calculate the mean and median temperatures for a five-day period Graph and analyze temperature data for a twelve-month period Describe six different climate types Construct and interpret a climate graph Investigate how energy from the sun heats earth surfaces Describe how latitude and ocean currents affect climate Identify local factors that affect climate Identify the metric units used to measure air pressure Calculate the mean and median air pressure for a five-day period Graph and analyze temperature data for a twelve-month period Explain how the earth s atmosphere changes with altitude Design a tool to measure wind direction or speed Investigate how the earth s atmosphere has changed over billions of years Describe several air pollutants in the atmosphere and their source Evaluate the change in air pollution for a city over a period of time Issues and Earth Science Student Sheet 50.2 E-11