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4 Teacher Edition 1 – 4 + days Weatherman’s Backpack [Key Science Knowledge Module] Activity Overview This module is the most important learning module in terms of the physical science aspects associated with weather and weather forecasting. Teachers have a great deal of flexibility in terms of the material covered in this learning module necessary to meet the objectives of the entire set of decision making and weather learning modules. The teacher can use their own lessons and textbook for meteorological material. Or, the teacher can use the suggested material in this learning module. The material is designed as a jigsaw approach to learning. It will take four or more days to complete the jigsaw approach. Another option is to skip the Weatherman’s Backpack material and have the students complete only the Becoming an Expert material. A third option is to skip the “Becoming an Expert Section” and go straight to students filling out the “Weatherman’s Backpack.” This will shorten the time requirements by approximately two days. Finally, the teacher can use their own meteorological lessons. Experiments will add to the overall time requirement. The teacher should do the activities appropriate for their class. 2. Demonstrates safe practices during field and lab investigations. 3. Implements investigation of hot/cold air fronts using water model. 4. Makes observations on the action of the hot/cold fronts. 5. Communicates conclusions. 6. Represents the natural world using models. 7. Collects, analyzes, and records information using tools. 8. Identifies the role of atmospheric movement in weather change. 9. Understands and is able to read a weather map. 10. Identifies and defines the symbols present on a weather map. 11. Recognizes local weather patterns. 12. Lists other factors that affect the forecast for rain. Teaching Summary Step 1 Journal/Bell Work- If Appropriate Step 2 Jigsaw Approach to Weatherman’s Backpack There is flexibility in this step as discussed in the activity overview and the three replacement steps 3-5. Student Learning Objectives (Depends on material and activities covered in completing the learning module) Step 3 - Replaces Step Two Becoming an Expert - only The student 1. Works cooperatively in groups. Step 4 - Replaces Step Two Weatherman’s Backpack – only 2 Weather Folklore Step 5 - Replaces Step Two Teacher’s own material Smoke rising straight into the air means fair weather and smoke hanging low means rain is on the way. Step 6 - Optional Science Experiments Step 7 – Optional Weather Map Drawing and Inference Activities Step 8 Homework / Assessment Materials Needed For The Teacher Weather map (transparencies, handout) Becoming an Expert Handouts Weatherman’s Backpack handouts Possible scientific basis, taken from Stalking the Wild The Magazine of Outdoor Discovery “How to Forecast Weather by Nature.” http://www.stalkingthewild.com/weather.htm “With the high pressure approaching and the air becoming denser, smoke will rise whereas with low pressure it can’t rise and tends to lay low.” Music Selection Clarence Clearwater Revival / John Fogerty Who’ll Stop the Rain Each student group will need computer access to Jetstream Online School or a print out of the material. A copy of the material is provided in a separate file. Teaching Suggestions http://www.srh.weather.gov/srh/jetstream Step 1 - Journal / Bell Work Divide the students into “expert groups.” Place a weather map transparency on an overhead project. Note to the students that weather is influenced by many factors. Have the students make a list of the factors that influence or make up weather. Use the weather map as a starting point. Use a weather map found in the local paper or use the map provided in this on the next page. For the Student Weather map handout - optional Becoming an Expert Handouts Weatherman’s Backpack handouts National Standards Module provides integrated approach to address science, math, reading and geography national standards. See Teacher Guide for specific standards addressed for grades 5-8. Texas Essential (TEKS) Knowledge and Skills Module provides integrated approach to address science, math, reading, and geography standards. See Teacher Guide for specific standards addressed for grades sixth, seventh, and eighth. Teacher Activity Options (select one) 1. Directly field student responses and put them on the board. 2. Have students brainstorm in groups and identify at least 3 factors that might affect the forecast for rain. 3. Have a student become the teacher and allow them to field answers and write them on the board (this option may take additional time). 4. Have students write their responses in their journals. 3 Weather Forecast Map for North America NOAA April 05, 2005 4 Step 2 – Jigsaw Approach to Weatherman’s Backpack For teachers not familiar with the jigsaw approach to learning, a brief overview of this method is provided in Appendix A of this Learning Module. In the Weatherman’s Backpack there are nine interrelated topics: air masses, fronts, precipitation, air pressure, heat transfer, earth-atmosphere energy, cloud formulation, wind, and jetstreams. Based upon instructional needs and curriculum of your class, select the appropriate weather topics. Air pressure, fronts, and precipitation are necessary for Learning Module 5. Teacher Activity – Jigsaw Approach The jigsaw approach divides the class into groups. Each group goes through a self-directed learning activity to become “experts” on a particular topic. Groups are then reassembled with one student moving from each group to another group. Each student teaches the material they had learned in their expert group to the members of the new group. 1. Divide the students into “expert groups.” Groups should have 3-6 students. One expert group is necessary for each weather topic to be covered. Each student in an expert group is given the appropriate “Becoming an expert on ___” handout. Each expert group also must have access to JETSTREAM An Online Weather School either online (website given in materials needed section) or printed material (provided in a separate file) associated with their expert group topic. 2. Each expert group completes their worksheet on Becoming an Expert on ___. 3. New student groups are formed with each student being an expert on a particular topic. The experts teach their particular topic to the other students in the reformed group using the Becoming an Expert on ___ worksheet. In teaching the topic, the students answer the questions associated with each topic in the Weatherman’s Backpack. 4. Redo teaching activity 3 until all students have completed their Weatherman’s Backpack. Step 3 - Replaces Step 2 – Becoming an Expert – only Using this option, the teacher skips the “Weatherman’s Backpack” material and students only complete the “Becoming an Expert” material. In the expert material there are nine interrelated topics: air masses, fronts, precipitation, air pressure, heat transfer, earth-atmosphere energy, cloud formulation, wind, and jetstreams. Based upon instructional needs and curriculum of your class, select the appropriate weather topics. Air pressure, fronts, and precipitation are necessary for Learning Module 5. Teacher Activity Questions contained in the Becoming an Expert are completed using either direct instruction, individually by each student, or in student groups. Each student is given a copy of the appropriate topics in the “Becoming an Expert.” Depending on the method used, material from JETSTREAM An Online Weather School (either online or printed material in separate file – see necessary material section) is given to the individual student or a group of students. If groups are used, the material can be shared between groups. This sharing reduces the amount of material that must be handed out to students. 5 Step 4 - Replaces Step 2 - Weatherman’s Backpack – only Using this option, the teacher skips the “Becoming an Expert on ___” material and proceeds directly to the Weatherman’s Backpack. In the Weatherman’s Backpack there are nine interrelated topics: air masses, fronts, precipitation, air pressure, heat transfer, earthatmosphere energy, cloud formulation, wind, and jetstreams. Based upon instructional needs and curriculum of your class, select the appropriate weather topics. Air pressure, fronts, and precipitation are necessary for Learning Module 5. Teacher Activity Questions contained in the Weatherman’s Backpack are completed using either direct instruction, individually by each student, or in student groups. Each student is given a copy of the appropriate topics in the “Weatherman’s Backpack.” Depending on the method used, material from JETSTREAM An Online Weather School (either online or printed material in separate file – see necessary material section) is given to the individual student or a group of students. If groups are used, the material can be shared between groups. This sharing reduces the amount of material that must be handed out to students. As with teaching the science topics, a great deal of flexibility is available with the science experiments. Teachers have a multitude of sources for relevant experiments including textbooks and online sources. Three suggested experiments are provided. Teachers can choose to use no experiments, one or more of these experiments or experiments from other sources. Suggested Experiments in Appendix B Probability Activity - Understanding the Difficulty in Forecasting the Future is designed to show students the difficulty associated with weather forecasting as the forecasts are for periods farther into the future. Hot / Cold Water Experiment is designed to illustrate how different temperature air masses interact with each other. Temperature Around Town - Impact of Concrete and Asphalt is designed to help students realize that there are local differences in weather (micro-climates) and explore what might cause these variations. Step 7 – Weather Map Drawing and Inference Activities – Optional Two weather map related activities are provided. These activities are to be completed after completion of the Weatherman’s Backpack. The two activities are: “Drawing a Weather Map” and “Making Inferences from a Weather Map.” Step 5 –Teacher’s Own Material – Optional The teacher can chose to use their textbook or own science concept materials. The first activity provides the student with a blank map and a series of statements. Using these statements, the student is to draw a weather map to represent that day’s forecast. Step 6 - Science Experiments - Optional Science experiments are not necessary to complete this learning module and the associated decision making modules. Science experiments do, however, increase student comprehension of the science topics. Additional time is necessary to complete the learning module as experiments are added. In the second activity, the student is given a completed weather map and answers questions based on the map. 6 Step 8 - Assessment / Homework Assessment Options 1. Weatherman’s Backpack. 2. Journal reflection: What information did you learn today? 2. Have students conduct research on one or more weather folklores. 3. Have students visit the national weather service web site and the weather channel web site. Obtain forecasts for cities other than your own city. Do the forecasts for a given city vary between the two websites? 3. Experiments and Write-ups Struggling Learners 4. Weather map activities. 1. If using the jigsaw approach become experts in pairs instead of individuals. Pair struggling learners with a peer tutor. Homework Options 1. Continue Weather Journal. 2. Suggested Experiment Temperature Around Town - Options 1, 3, and / or 4. 3. Weather map activities. Enrichment Options 1. Have students visit / interview a local meteorologist. 2. If completing the weatherman’s backpack individually, provide a set of reading that highlights the answers. 3. In completing the weatherman’s backpack, use the multiple-choice option instead of the open ended set of questions. 4. Use peer tutors to help students collect the data for the experiment options. 7 Learning Module Related Material Becoming an Expert on Weather Topics Pages 8 - 21 Questions associated with “Becoming an Expert” on the nine interrelated topics: air masses, fronts, precipitation, air pressure, heat transfer, earth-atmosphere energy, cloud formulation, wind, and jetstreams are provided on the following pages. Questions are based on JETSTREAM An Online Weather School http://www.srh.weather.gov/srh/jetstream. The JETSTREAM material is also provided in separate files. Weatherman’s Backpack Pages 22 - 31 The Weatherman’s Backpack contains pages for the same topics as Becoming an Expert. Probability Activity - Understanding the Difficulty in Forecasting the Future Pages 32 - 33 Hot/Cold Water Experiment Pages 34 -35 Temperature around Town - Impact of Concrete and Asphalt Experiment Page 36 Drawing a Weather Map Page 37 Making Inferences from a Weather Map Page 38 Appendix A - Weatherman’s Backpack – Jigsaw Approach Page 39 8 Becoming an Expert on Air Masses To become an expert on air masses, read the information on air masses and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.weather.gov/srh/jetstream/synopt ic/airmass.htm 1. What is an air mass? Large body of air with uniform temperature and humidity 4. What are the four principal air mass classifications that influence the U.S. according to their source region? Polar latitudes Continental Maritime Tropical latitudes 5. Do air masses always maintain their original characteristics? Explain why or why not. No, passing over an area, the air mass may pick up the characteristics of the area. For example, passing over an ocean an air mass may pick up moisture and warmth 2. What is a source region? The area from which an air mass originates 3. Why is the U.S. not a favorable source region? Frequent passages of weather disturbances that disrupt air masses that do not allow the air mass to stagnate and take on the properties of the underlying region 6. A cold dry artic (polar) air mass may pick up what characteristics as it passes over an ocean? Warmth and moisture 7. How long can air masses control the weather over a given area? Days to months 8. Where do most changes in weather occur? Along the periphery or boundaries called fronts 9 Becoming a Expert on Fronts To become an expert on fronts, read the information on fronts and complete the questions. Your textbook is also a good source of information on weather. 7. What is an occluded front? -Cold front is undercutting the warm front Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.weather.gov/srh/jetstream/synopt ic/airmass.htm 1. What is a front? 8. Draw the symbols and color for each type of front, cold, warm, and stationary. Cold – blue - warm – red Boundary between two air masses Stationary – red and blue 2. How are fronts classified? Occluded – purple By which type of air is replacing e.g. with a cold front, cold air is replacing warm air 9. How are weather patterns different between warm and cold fronts? 3. What are the four types of fronts? Cold, warm, stationary, and occluded fronts 4. What is a cold front? A cold air mass replacing warm air 5. What is a warm front? Warm air replacing cold air 6. What is a stationary front? A front that is not moving Warm – widespread layered stratiform clouds with precipitation along and to the north of the front Cold – narrow band of showers and thunderstorms 10. Which type of front usually moves faster? Cold 11. State three ways fronts are detectable at the earth’s surface. Winds come together at air mass boundaries (fronts) Large temperature differences Pressure differences 10 Becoming a Expert on Precipitation To become an expert on precipitation, read the information on precipitation and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/srh/jetstream/synoptic/ precip.htm. 4. How is the moisture transported from the source to inland areas? Winds around high and low pressure systems 5. What is the most effective way for clouds to form? Provide two ways clouds form. Know / review the following before reading JETSTREAM. Drought - a long period of very low rainfall that can have affects on growing or living conditions. 1. List at least three common forms of precipitation. Rain, snow, sleet, hail, and freezing rain 2. What four components are necessary for precipitation to form? (Hint: see the next four questions to help you with your answer.) Source of moisture Winds to transport the moisture Clouds must form Process to allow water droplets to grow large enough to fall 3. What are the three primary sources of moisture for precipitation in the U.S.? Pacific and Atlantic Oceans and the Gulf of Mexico Lifting the air - by going over mountains or forcing the air to rise near fronts and low pressure areas 6. How do the water drops in a cloud grow large enough to fall as precipitation? Collisions between water droplets and they stick together to form larger drops which eventual will fall as rain 7. What often determines the type of precipitation (rain, snow, sleet) during the winter? Vertical distribution of temperature 8. What is a temperature inversion? Air temperature increases with height before decreasing again 11 9. Draw the vertical distribution temperatures for snow. of air 11. Draw the vertical distribution temperatures for freezing rain. of air 12. What causes the freezing rain to form instead of sleet? 10. Draw the vertical distribution temperatures for sleet. of air Warm layer is deep enough making the cold layer at the surface is too shallow for the water to freeze into sleet 13. What is drought? Long periods of unusually low precipitation 12 Becoming an Expert on Air Pressure To become an expert on air pressure, read the information on air pressure and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM, An Online Weather School http://www.srh.noaa.gov/srh/jetstream/atmos/pre ssure.htm an additional source is http://kids.earth.nasa.gov/archive/air_pressure/ . Know / review the following before reading JETSTREAM Because air has mass it has the property of pressure. Air pressure is result of weight of air pushing down on an area or surface. In meteorology, two terms are commonly used to indicate the air pressure in a system, high or low. The symbol for a high-pressure system is a capital “H.” The symbol for a low- pressure system is a capital “L.” Rising or high air pressure generally brings fair weather, whereas decreasing or low air pressure generally brings bad (rain and wind) weather. The differences in pressure cause winds. Winds move from highpressure to low-pressure areas. Differences in pressure on the earth are caused by unequal heating of the earth’s surface. 1. What makes up the atmosphere or the air we breath? how Air pressure is simply the weight of air surrounding an object. 4. How is air pressure associated with air molecules? Air pressure depends on the number of air molecules in a given space and how fast the molecules are moving. 5. Why does the air pressure decrease the higher a person goes up into the atmosphere? As elevation increases, less air molecules are available and the weight of air therefore is less, meaning a decrease in air pressure. 6. What is a millibar? The amount of force it takes to move an object weighing one gram, one centimeter, in one second. 7. If you were on a mountain, would the weight of the air above you (air pressure) be greater than or less than it is now? Atoms and molecules 2. Describe 3. What is air pressure? we feel air pressure. As the number of molecules of air around you decreases, the air pressure decreases. The atoms and molecules that make up air exert weight on us. We feel this weight as pressure. 13 8. Do you think winds are related to air pressure? How? Some winds are caused by differences in air pressure, which are the results of unequal heating of Earth’s surface. Temperature differences can also cause wind. 9. What is the symbol for a high-pressure system? H 10. What is the symbol for a low-pressure system? L 11. What type of weather is usually associated with rising or high-pressure areas? Fair weather 12. What type of weather is usually associated with decreasing or low-pressure areas? Poor weather rain 14 Becoming an Expert on Heat Transfer To become an expert on heat transfer, read the information on heat transfer and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/srh/jetstream/atmos/he at.htm. 5. What is radiation? Radiation is the transfer of heat energy by electromagnetic radiation. 6. What happens to most of the solar energy that reaches the earth’s surface? Know / review the following before reading JetStream. Heat - a form of energy associated with motions of atoms or molecules that can be transmitted through solid, fluid, or empty space, by convection, conduction, or radiation, the degree of hotness. Solar energy that reaches the earth is radiated back into the atmosphere to become heat energy. 1. Where does most of energy that keeps Earth warm come? Sun 2. What is heat? The energy transferred from a hotter object to a cooler one is referred to as heat. 3. What are the three ways heats is transferred, into the atmosphere? It is radiated back into the atmosphere to become heat energy. 7. Give an example of conduction heating. - touching a hot object 8. What is conduction? Conduction is the transfer of heat energy from one substance to another or within a substance. 9. Give an example of convection heating. Water boiling on a stove 10. What is convection? Convection is the transfer of heat energy by the movement of a fluid. Radiation, conduction, and convection 4. Give an example of radiation heating. Fireplace 15 11. Describe the process in which a warm bubble of air is formed by heat energy. The sun’s radiation strikes the ground, warming the rocks, whose temperature rises due to conduction. Heat energy is then released into the atmosphere forming the bubble of air that is warmer than its surrounding air. 12. What type of heat causes most of the heating of the layer of the atmosphere closest to the earth’s surface (troposphere)? Convection 13. How can heat transfer in the atmosphere cause wind? The hot air that is rising is replaced by surrounding cooler air causing wind. 16 Becoming an Expert on Earth-Atmosphere Energy To become an expert on Earth-Atmosphere Energy Balance Expert, read the information on earth-atmosphere energy balance and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/jetstream/atmos/energy .htm. 1. The earth-atmosphere energy balance refers to the balance of energy coming from what and leaving from what? Incoming from the Sun and outgoing from the earth 2. Energy from the sun is emitted in what two main forms? Short wave light and ultraviolet energy 3. What three things happen to the energy from the sun when it reaches the earth? 6. What effect causes the earth to have a higher average temperature than the moon? Greenhouse effect 7. What is the greenhouse effect? Heating effect caused by having an atmosphere 8. Why is the average surface temperature of the moon only 0○ F, while the average surface temperature on the earth is 59○ F? Because the earth has an atmosphere and the moon does not 9. Explain why, everything else being equal, the temperature on a cloudy night will be higher than the temperature on a clear night. Draw a picture of what happens on a cloudy and a clear night. Reflected back to space by clouds, absorbed by the atmosphere, and absorbed by the earth’s surface 4. Name one way one can see energy radiating (leaving) the earth’s surface. Rising heat off a road, creating shimmers on hot sunny days 5. How does the earth maintain a stable average temperature and climate? Energy lost is balanced by energy gained from the sun Heat energy from the earth is trapped by the clouds 17 Becoming an Expert on Cloud Formulation To become an expert on clouds, read the information on clouds and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/srh/jetstream/synoptic/ clouds.htm. Know / review the following terms before reading JetStream. Dew point: the temperature at which water condensation begins. Condensation: is the process whereby water vapor in the atmosphere is returned to its liquid state. In the atmosphere condensation may appear as clouds, fog, mist, dew, or frost, depending on the physical conditions of the atmosphere. 3. From question 2 you learned rising air cools, why does this cooling cause condensation? Hint: explain in relation to water vapor. Because cold air can hold less water vapor than warm air 4. Why do clouds tend to evaporate as air sinks? As air sinks it is under more pressure that adds heat to the air, warm air can hold more water vapor so clouds evaporate. 5. What are the four basic cloud categories (forms)? Cirro, nimbo, cumulo, and strato Saturation: condition in which air at a specific temperature contains all the water vapor it can hold, which is at 100% relative humidity. 1. What two things can cause clouds to form? Clouds form when air is cooled to its dew point or when the air reaches saturation. 2. Why does rising air cool? The warmed air near the ground rises as a bubble or parcel of air. When the rising air expands, it loses heat and becomes cooler. 6. Describe cirro clouds? What type of weather are cirro clouds usually associated with? Wispy, feathery high level clouds composed of ice crystals. Usually indicates fair weather. 7. Describe nimbo clouds? What type of weather are nimbo clouds usually associated with? Thick clouds forming between 7,000 and 15,000 feet. Steady rain. 18 8. Describe cumulo clouds? What type of weather are cumulo clouds usually associated with? - cumulo clouds look like fluffy, rounded piles of cotton. Usually indicates fair weather. 9. Describe strato clouds? What type of weather are strato clouds usually associated with? Featureless low level clouds that can cover all or most of the sky. Gray and dull weather. As stratus clouds thicken, they may produce drizzle, rain, or snow. 19 Becoming an Expert on Wind To become an expert on wind, read the information on wind and complete the questions. Your textbook is also a good source of information on weather. Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/srh/jetstream/synoptic/ wind.htm. 5. What is meant by vertical wind and why are these winds important? Air rising and sinking – important in day to day weather. 6. Why does rising air often lead to clouds and precipitation? Read up to Coriolis force. 1. What is wind? Rising air becomes cool, often to saturation, and condenses to form clouds because cool air holds less water vapor. Rain and other forms of precipitation fall from the clouds. Air in motion 7. Why does sinking air result in fair weather? 2. In what direction, horizontal or vertical are we usually taking about we discuss wind? Horizontal 3. What does a forecast of east winds of 30 to 40 mile per hour (mph) mean? Sinking air becomes warm causing evaporation of clouds because warm air can hold more water vapor and thus fair weather. 8. Besides temperature, which causes air to rise (increase in temperature) and sink (decrease in temperature), what is the other main factor that causes wind? Horizontal winds will be 30 to 40 mph from the east Differences in air pressure. 4. What can you observe that will indicate if the wind is blowing? By observing physical factors such as leaves rustling, trees moving, waving water, swaying flags, and so on. 9. What is the wind direction around a highpressure system? Clockwise 10. What is the wind direction around a lowpressure system? Counterclockwise 20 11. As the gradient (differences) in pressure between a high and low-pressure system increases, what happens to the wind speed? 12. Does warm or cool air hold more water vapor? When air cools it can hold less water vapor. Iincreases 21 Becoming an Expert on Jetstreams To become a n expert on jetstreams, read the information on jetgstreams and complete the questions. Your textbook is also a good source of information on weather. 6. Draw a figure that shows where polar and subtropical jet streams are generally located on the earth. polar Questions are based on the material presented in JETSTREAM An Online Weather School http://www.srh.noaa.gov/jetstream/global/jet.ht m. 1. subtropical subtropical What are jetstreams? polar Relatively narrow bands of strong wind in the upper levels of the atmosphere 2. What general direction does the wind blow in a jetstream? 7. How fast can the winds be in a jetstream? 275 mph West to east 3. Besides the direction mentioned in question 2, what other direction can jetstreams flow? 8. What variables are responsible for the actual appearance of jetsreams? High and low pressure sytems, warm and cold air masses, and seasonal changes North to south 4. What do jetstreams follow? Boundaries of hot and cold air 5. Why are jetstreams most pronounced during the winter? Hot and cold air boundaries are most pronounced during the winter 9. In the spring, how does the jetstream help bring warmer air to the U.S.? Polar and subtropical jetstreams shift north 10. In the autumn, how does the jetstream help bring cooler air to the U.S.? Both jetstreams shift south 11. When are jet streams the strongest? In both Northern and Southern hemisphere winters. 22 Weatherman’s Backpack Name: _____________________________ Class: _____________________________ Date: _____________________________ 23 Air Masses 1. What is an air mass? Large body of air with uniform temperature humidity. 3. Why is the U.S. not a favorable source region? Frequent passage of weather disturbances that disrupt air masses that do not allow the air mass to stagnate and take on the properties of the underlying region 5. How long can air masses control the weather over a given area? Days to months 2. What is a source region? The area from which an air mass originates. 4. A cold dry artic (polar) air mass may pick up what characteristics as it passes over an ocean? Warmth and moisture. 6. Where do most changes in weather occur? Along the periphery or boundaries called fronts. 24 FRONTS 1. What is a front? Boundary between two air masses. 3. What is a cold front? Draw the symbol for a cold front. Be sure to use the correct colors. Cold air is replacing warm air. 5. What is a stationary front? Draw the symbol for a stationary front. Be sure to use the correct colors. A front that is not moving. 2. How are fronts classified? By which type of air the front is replacing, e.g. a cold front – cold air is replacing warm air. 4. What is a warm front? Draw the symbol for a warm front. Be sure to use the correct colors. Warm air is replacing cold air. 6. How are the weather patterns different between warm and cold fronts? warm – widespread layered stratiform clouds with precipitation along and to the north of the front cold – narrow band of showers and thunderstorms 25 Precipitation 1. List at least three common forms of precipitation. rain, snow, sleet, hail, and freezing rain 3. What are the three primary sources of moisture for precipitation in the U.S.? Pacific and Atlantic Oceans and the Gulf of Mexico 5. What is the most effective way for clouds to form? Provide two ways clouds form. 2. What four components are necessary for precipitation to form? 1) source of moisture 2) winds to transport the moisture 3) clouds must form 4) process to allow water droplets to grow large enough to fall 4. How is the moisture transported from the source to inland areas? winds around high and low pressure systems 6. What often determines the type of precipitation (rain, snow, sleet) during the winter? vertical distribution of temperature lifting the air - by going over mountains or forcing the air to rise near fronts and low pressure areas 7. What is the difference in the atmosphere between snow forming or sleet forming? a shallow warm layer of air is necessary for sleet to form, but is not present when snow forms Instrument: rain gauge Units: inches or millimeters Symbol note: the symbols for precipitation on a weather map are usually the words snow, rain, sleet, and thunderstorms – with a semi to full circle showing the area where the precipitation will occur. 26 Air Pressure 1. What makes up the air we breath? atoms and molecules 3. Describe how we feel air pressure. The atoms and molecules that make up air exert weight on us. We feel this weight as pressure. 5. Why does the air pressure decrease the higher one goes into the atmosphere? as elevation increases, less air molecules are available and the weight of air therefore is less, meaning a decrease in air pressure. \ 2. What is air pressure? Air pressure is simply the weight of air surrounding an object. 4. How is air pressure associated with air molecules? Air pressure depends on the number of air molecules in a given space and how fast the molecules are moving. 6. What are the symbols for high- and lowpressure systems? H – high L – low 7. What type of weather is associated with a high-pressure system and a lowpressure system? H- fair L – stormy Instrument: Barometer Units: millibars or inches of mercury 27 Heat Transfer 1. In what three ways can heat be transferred? By radiation, conduction, and convection. 3. What is conduction? 2. What happens to most of the solar energy that reaches the earth’s surface? It is radiated back into the atmosphere to become heat energy. 4. What is convection? The transfer of heat energy in a fluid. The transfer of heat energy from one substance to another within a substance. 5. What is radiation? Transfer of heat by electromagnetic radiation.. 7. Describe the process in which a warm bubble of air is formed by heat energy. The sun’s radiation strikes the ground, warming the rocks, whose temperature rises due to conduction. Heat energy is then released into the atmosphere forming the bubble of air that is warmer than its surrounding air. Instrument: Thermometer Units: Degrees 6. How can heat transfer in the atmosphere cause wind? The hot air that is rising is replaced by surrounding cooler air causing 28 Atmosphere Energy 1. What three things happen to the energy from the sun when it reaches the earth? reflected back to space by clouds, absorbed by the atmosphere, and absorbed by the earth’s surface 3. What is the greenhouse effect? heating effect caused by having an atmosphere 5. Why do cloudy nights tend to be warmer? 2. How does the earth maintain a stable temperature and climate? Energy received from the sun balances energy lost by earth back into space. 4. Why does the moon’s and earth’s average surface temperatures differ? earth has an atmosphere and the moon does not 6. When are nights the coolest? When there are clear skies. Heat energy from the earth can be trapped by clouds, leading to warmer nights. 29 Clouds 1. What two things can cause clouds to form? clouds form when air is cooled to its dew point or when the air reaches saturation. 3. Why does rising air cool? the warmed air near the ground rises as a bubble or parcel of air. When the rising air expands, it loses heat and becomes cooler. 5. Describe nimbo clouds? What type of weather are nimbo clouds usually associated with? thick clouds forming between 7,000 and 15,000 feet. Steady rain. 7. Describe strato clouds? What type of weather are strato clouds usually associated with? featureless low level clouds that can cover all or most of the sky. Gray and dull weather. As stratus clouds thicken, they may produce drizzle, rain, or snow. 2. Why do clouds tend to evaporate as air sinks? as air sinks it is under more pressure that adds heat to the air, warm air can hold more water vapor so clouds evaporate. 4. Describe cirro clouds? What type of weather are cirro clouds usually associated with? Wispy, feathery high-level clouds composed of ice crystals. Usually indicates fair weather. 6. Describe cumulo clouds? What type of weather are cumulo clouds usually associated with? cumulo clouds look like fluffy, rounded piles of cotton. Usually indicates fair weather. 30 Winds 1. Why does rising air often lead to clouds and precipitation? rising air becomes cool, often to saturation, and condenses to form clouds because cool air holds less water vapor. Rain and other forms of precipitation fall from the clouds. 3. Why does sinking air result in fair weather? sinking air becomes warm causing evaporation of clouds because warm air can hold more water vapor and thus fair weather. 5. Does warm or cool air hold more water vapor? when air cools it can hold less water vapor. Instrument: Wind vane - direction Units: Compass directions Instrument: Anemometer – wind speed Units: Miles per hour or kilometer per hour 2. What does sinking air do and what weather does it cause? Sinking air warms causing evaporation of clouds, and fair weather. 4. What is the pressure gradient? How does it impact wind speed? The difference in pressure between high and low pressures. The higher the gradient the faster the wind speed. 6. What must happen as the air spreads away from the highs? Air from above must sink in to replace it. 31 Jetstream 1. What are jet streams? 2. When are jet streams the strongest? A relatively narrow band of strong wind in the upper levels of the atmosphere. 3. Draw a figure that shows where polar and subtropical jet streams are generally located on the earth. In both Northern and Southern hemisphere winters. 4. In the spring, how does the jetstream help bring warmer air to the U.S.? polar and subtropical jetstreams shift north polar subtropical subtropical polar 5. What speed can jet streams reach? Jet streams can reach speeds of more than 275 miles per hour. 6. In the autumn, how does the jetstream help bring cooler air to the U.S.? both jetstreams shift south 7. What general direction does the wind blow in a jetstream? west to east 32 Probability Activity - Understanding the Difficulty in Forecasting the Future 4. Record if the ball landed in the box or the toss missed the box. Teacher Action - Setup 1. Divide the class into groups of 3-5 students. Each group must have a nerf ball, forecast box, and blank data table. 2. Students need to complete the data table, by tossing the nerf ball into the forecast box at various distances from the box. 3. Students need to answer the questions after the data table. Objective To illustrate as people forecast farther into the future, the harder it is to provide good forecasts. Materials One nerf ball and one forecast box for each group 5. Complete the questions following the data table as a group. Concept Tossing the nerf ball represents making a forecast. The forecast can be for weather, the stock market, or any other event you may want to forecast. The idea remains the same for all forecasting. The distance from the box represents the future you are forecasting as given by the following timeline. Another concept this activity can illustrate is as follows: let the further away steps indicate lack of knowledge. As knowledge increases, the student moves closer to the box. Getting the nerf ball in the box represents correct understanding of the concepts / principles. Illustrate why people need to be educated. Procedures 1. Read the concept and understand the timeline. 2. Place the forecast box on the floor. 3. As a group, complete the data table by trying to toss the nerf ball into the forecast box at different distances from the box. Elect one student to be the thrower and use the same student for all throws. This eliminates differences in throwing skills. Distance 1 step 3 steps Day Today Tomorrow In this timeline, it is currently today. One step represents forecasting this afternoon, given the conditions in the morning. Three steps represent forecasting tomorrows conditions based on the conditions in the morning today. Five steps represent forecasting two days into the future using today’s current conditions. Finally, 10 steps represent forecasting a week into the future. The nerf ball landing in the box represents two things 1) ease of making the forecast and 2) how good the forecast is. 5 steps 10 steps 2 days into the future 1 week into the future 33 Data table for tossing the nerf ball. Place a one (1) in the table if the toss landed in the box, toss made, and a zero (0) if the toss failed to land in the box. Toss 1 step 3 steps 5 steps 10 steps 1 2 3 4 5 6 7 8 9 10 Total the tosses made Questions 1. At what distance were the most tosses made? 2. What is the relationship between the number of tosses made and the distance from the forecast box? 3. Recall, the tosses made represent a “good” forecast. At what distance did you have the most “good” forecasts? 4. What is the relationship between the number of “good” forecasts and the number of days into the future? 5. Provide some reasons why you found the relationships in question 4 between forecasts and distance into the future. 34 Hot/Cold Water Experiment Now that students are familiar with the terminology, discuss with them the local weather patterns. What might cause changes in local or microclimate weather? ** Read through the entire procedure first, and then write down your hypothesis BEFORE beginning. Procedure: For example, ask “How is the movement of cold air masses different from that of hot air masses?” Density and Weather Much of what we call “weather” is caused by the differences in the density of different air masses. Because it is difficult to see the movement of air masses, we will observe the movements of liquids with different densities. (Remember that liquids and gases are very similar in the way they move, except liquids ‘move’ slower!) Purpose: To discover how different temperature air masses interact with each other. Hot Cold 1. Fill the plastic box about 2/3 with room temperature water. Let the tub of water sit still in a position so all members can see it. WRITE YOUR HYPOTHESIS WHILE THE WATER IS ‘RESTING’. 2. Fill one small beaker with hot water. Add several drops of red food coloring to color it red. Stir the coloring around with a stir stick. 3. Fill the other beaker with cold water. Add several drops pf blue food coloring to color it blue. Stir the coloring around with a stir stick. 4. Gently place the two beakers into opposite ends of the tub of water. The top of the beakers should be above the water. Let the water come to rest for a minute or two. 5. At the same time, gently tip the two beakers towards the center of the pan of water. Let the beakers lay on the bottom of the tub. Be sure to remove your hands as gently as possible so as to not disturb the water. LEAVE THE BEAKERS THERE – DO NOT TAKE THEM OUT! ** Read through the entire procedure first, and then write down your hypothesis BEFORE beginning. Hot Cold Hypothesis: If I mix cold water and hot water together in a tub of water, the (write your hypothesis here concerning the water mixture) 6. OBSERVE! Begin timing. During this time, DO NOT MOVE THE DESKS! 35 c. Make one final observation from the top of the box looking down into the tub. Draw what you see. 7. After each time interval below, sketch how the tub of water appears from the side? a. After 10 seconds it looked like this: a. After 60 seconds it looked like this: Hot Cold b. After 60 seconds it looked like this: CLEAN UP: Carefully pour the water into the sink. Return all materials as where they were when you began. \ 8. Was your hypothesis correct? Hot Cold b. After 2 minutes it looked like this: Hot 9. Explain your observations. (WHY did the hot water in the tub do what it did? WHY did the cold water do what it did?) Cold 10. Since liquids and gases act the same way, what does this tell you about the movement of cold air and war, air? _ 36 Differences in Local Weather Objective: Help students realize that there are local differences in weather (micro-climates) and explore what might cause these variations. Teacher asks, “Now that we have seen some of the types of weather we have in our town, what differences are there inside the town itself”. Option 1: Your City Temperature Variation around Equipment Required: Thermometers for each student Method: Have the students take the thermometers home and read the temperature at two set times (am and pm), and record the temperature. The teacher will have a city map posted in the classroom and the students will put their temperature reading on the map each day with a different colored pen for the am and pm temperatures. The teacher will record the official temperature at the am and pm times for the local city. Students will calculate the difference from their temperature and the reported temperature for the town. Ask students to list what might have caused the temperature differences (e.g. concrete, asphalt, grass, trees causing shade etc). Option 2: Temperature Variation around the School Grounds Equipment Required: Thermometer for each student Method: Same as Option 1 except have the students take temperatures around the school grounds. Have a map of the school grounds and have students put the different temperatures on the map. Are there any temperature differences between the parking lot, playground, and lawn areas? Question to have students answer is, “How much area do you need to observe slight temperature differences?” Do this on both a cloudy day and a sunny day, are there differences on both days. Which day has the most variation? Why? Option 3: Temperature Variation around Students’ Homes Equipment Required: Thermometer for each student Method: Have students take temperature measures around their home at 5 time intervals during the next Saturday (e.g. 9 am, 12 noon, 3 pm and 7 pm). Have students create a table of temperatures at five locations around their home at these times. Ask students to identify factors that cause these temperature changes during the day. Identify which students found the most variation around their house and ask them to explain why they had this much variation. Option 4: Rainfall Variation Equipment Required: rain gauge for each student (may be available from local hardware, lumber, machinery or farm supply stores in country, at little or no cost). Large pill bottles from a pharmacy or film canisters will also work. Methods: Have the students measure the amount of precipitation over one week at their home. Compare this to the official rainfall for the town. Have each student enter the amount of rainfall at the students’ homes on a map of the school district. Have the students identify reasons why the rainfall might be different. 37 Drawing a Weather Map Snow H L Rain Draw the following weather factors on the map of North America, using your Weatherman’s Backpack. Be sure to use the correct symbols and colors. 1. Place a high-pressure system to the west of the Great Lakes in central U.S. 5. Show that rain is possible in the along the western Gulf of Mexico coast. 2. Place a low-pressure system over the southeastern U.S. 6. Draw a cold front approaching western U.S. from the Pacific Ocean. 3. Draw a warm front that extends from the southwestern U.S., between the two above pressure systems to the northeastern U.S. 7. Show that snow is possible in front of the cold front in the western U.S. 4. Draw a stationary front that goes from the Gulf of Mexico through Florida to the Atlantic Ocean. 38 Making Inferences from a Weather Map Answer the following questions based on the attached weather map and your knowledge from the Weatherman’s Backpack activity 1. Where would you expect heavy rains in the U.S? West Texas 2. What kind of front runs from the Gulf of Mexico through Florida to the Atlantic Ocean? 4. How will the temperature be changing in the next few days in the area of Great lakes? Warm to cold 5. How will the precipitation outlook change in the next few days in the area of Great lakes? Clear changing to rain Stationary front 3. What kind of weather would be expected in western Canada? Snow 6. What kind of weather would be expected in northwestern U.S.? Rain 39 Appendix A Weatherman’s Backpack – Jigsaw Approach One method of teaching is the jigsaw approach. In this approach, students are placed into groups. Each group becomes the “expert” in a particular topic. After the groups have completed the expert materials, new groups are formed with an expert from each topic in the new group. An example for three topics is given in the figure below. Each box represents a group. In this setup, Claudia, Jose, and Fred become experts on air masses, Seth, Cindy, and Lebron become experts on precipitation, and Ivan, Megan, and LeAnn are the winds experts. Each expert member then teaches their topic to students in the new group. For example, in new group 1, Claudia would teach air masses, Seth precipitation, and Ivan winds. New groups 2 and 3 would be similar. In teaching the material in the new groups, each student in the class, finishes their Weatherman’s Backpack. the National Weather Services JETSTREAM, Online Weather School, http://www.srh.weather.gov/srh/jetstream. Each area provides a links to specific web pages. Included are nine topic, the teacher should modify the content as appropriate for their classroom setting. JETSTREAM contains many more topics. Online School is used with permission from the National Weather Service. Suggested Expert and Weatherman’s backpack materials are provided. The material is based on The jigsaw idea can be modified to fit your textbook. . Each expert material contains 8 - 15 questions designed to provide the student the necessary knowledge to help fellow students complete the Weatherman’s Backpack. The Backpack provides questions that is a summary of necessary knowledge and as such provides a review sheet for testing purposes. The Backpack has approximately six questions on each area. Air Masses Claudia Jose Fred Precipitation Seth Cindy Lebron Winds Ivan Megan LeAnn New Group 1 Claudia Seth Ivan New Group 2 Jose Cindy Megan New Group 3 Fred Lebron LeAnn