Unit: Weather and Climate General Task Air pressure and Storms

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1 The following instructional plan is part of a GaDOE collection of Unit Frameworks, Performance Tasks, examples of Student Work, and Teacher Commentary. Many more GaDOE approved instructional plans are available by using the Search Standards feature located on GeorgiaStandards.Org. Standards (Content and Characteristics): Unit: Weather and Climate General Task Air pressure and Storms S6E4. Students will understand how the distribution of land and oceans affects climate and weather. b. Relate unequal heating of land and water surfaces to form large global wind systems and weather events such as tornados and thunderstorms. c. Relate how moisture evaporating from the oceans affects the weather patterns and weather events such as hurricanes. S6E6. Students will describe various sources of energy and with their uses and conservation. a. Explain the role of the sun as the major source of energy and its relationship to wind and water energy. S6CS8. Students will investigate the characteristics of scientific knowledge and how it is achieved. Students will apply the following to scientific concepts: a. When similar investigations give different results, the scientific challenge is to judge whether the differences are trivial or significant, which often requires further study. Even with similar results, scientists may wait until an investigation has been repeated many times before accepting the results as meaningful. b. When new experimental results are inconsistent with an existing, well-established theory, scientists may require further experimentation to decide whether the results are flawed or the theory requires modification. c. As prevailing theories are challenged by new information, scientific knowledge may change and grow. S6CS9. Students will investigate the features of the process of scientific inquiry. Students will apply the following to inquiry learning practices: a. Scientific investigations are conducted for different reasons. They usually involve collecting evidence, reasoning, devising hypotheses, and formulating explanations. b. Scientists often collaborate to design research. To prevent bias, scientists conduct independent studies of the same questions. c. Accurate record keeping, data sharing, and replication of results are essential for maintaining an investigator s credibility with other scientists and society. d. Scientists use technology and mathematics to enhance the process of scientific inquiry. July 24, 2007 Page 1 of 12

2 Enduring Understanding: Heat energy carried by ocean currents has a strong influence on climate around the world. The sun is the major source of energy for phenomena on the Earth's surface, including winds, ocean currents, and waves. Waves transfer energy from one place to another. Waves in oceans and lakes are caused by wind blowing over the surface of the water. Ocean currents influence the weather in coastal areas. Currents can be caused by wind, differences in salinity, differences in water temperatures caused by uneven heating of the Earth, the Coriolis Effect which is a consequence of the Earth's rotation, and the gravitational pull of celestial bodies (tidal currents). Essential Question(s): How does an ocean affect the weather and climate of adjacent land? How does the sun s heating of water in the tropics affect climate in the rest of the world? How does the sun s energy cause winds and hurricanes? Pre-Assessment: Teacher asks students if they think something heated (such as air) expands or contracts. Have students stand up. If they think heating makes things expand, they move to one side of the room (designated by the teacher). If they think heating makes something contract, they move to the other side of the room. As an option, students may model expansion or contraction by using their arms to show getting wider or getting narrower. Safety issues: In this lab, students will be blowing up balloons. Care should be exercised so that the students are instructed not to over inflate the balloons, to avoid bursting them. Safety goggles could also be worn by students blowing up balloons. Other students should be instructed not to stand close to the person blowing up the balloon. In addition, students should be instructed not to put balloons or pieces of balloons into their mouth, as they would be a choking hazard. Students should also not allow air from a deflating balloon to rush into their mouths, as balloons are commonly coated with powder to keep them from sticking together. This powder should not be ingested by students. As an option, a pump or air tank could be used to inflate balloons, with the teacher operating the device and wearing safety goggles. Students will be placing balloons in warm areas, such as under a heat lamp or 100 Watt light bulb. Students must use care not to touch the light bulb or burn themselves with it. Balloons should not be put in an oven. Care must be used with any source of heat. July 24, 2007 Page 2 of 12

3 Outcome/ Performance Level Indicator Performance Task: (Detailed Description) Teacher role? Student role? BASIC INTERMEDIATE ADVANCED Students will Relate unequal heating of land and water surfaces to form large global wind systems and weather events such as tornados and thunderstorms Relate how moisture evaporating from the oceans affects the weather patterns and weather events such as hurricanes Explain the role of the sun as the major source of energy and its relationship to wind and water energy. As an alternative, to Temperature and air simplify the pressure should be given the experiment, basic materials and asked students might be to create an given one balloon per experiment to show group, which is the effects of measured, and then temperature on air heated for 10 minutes, mass. The and later cooled for 10 experimental design minutes. This would must be approved make the data easier by the teacher prior to understand. to students. They could repeat the experiment with a second balloon if desired. The teacher may need to guide basic students in making predictions about the balloons. The teacher provides balloons to the class. Each group gets three balloons. The teacher should have extra balloons on hand. Students also need tape measures and containers with ice that are large enough to hold one balloon from each group (such as a cooler or refrigerator or sink filled with ice and water), and thermometers that can be put into the ice bath, in the area where room temperature balloons are kept, and in the warmer area under a heat lamp or 100W light bulb. The students blow the three balloons up to the same size (as nearly as possible) and tie them shut. The teacher asks the students what they think will happen if one balloon is cooled, one is kept at room temperature, and the other balloon is placed in a warm area (such as under a heat lamp or 100 watt light bulb, or near a heat source in the classroom). The third balloon should NOT be put in July 24, 2007 Page 3 of 12 Instructions to advanced students: Your supplies are out, your task is to figure out how to use the supplies to show how the temperature of air affects the amount of space the air takes up. should discuss possible outcomes to the differential heating/cooling of balloons exercise in small groups and write their predictions in their journals.

4 an oven. Balloons should be gently warmed if possible. The students should make predictions as to what the three balloons will do under the various conditions. Basic students may need assistance with measuring, marking, and recording data. The teacher may need to assist basic students with reading the thermometer or making the measurements. The students measure the circumference of the balloons using a tape measure, and record them in a data table. The circumference is the distance around the outside of the balloon. The students should use a marker and label the balloons 1, 2, and 3. They should also draw some marks on the balloons to indicate where the circumference was measured, so that they can measure that exact place again at a later time. Measurements should be made in centimeters, to the nearest tenth of a centimeter. Measurements should be written in decimal form (such as 18.6 cm). Students put the balloon marked 1 in an ice bath for 10 minutes. (This could be a cooler, refrigerator, or sink with ice and water in it.) A thermometer should be put into the ice bath alongside the balloon. The temperature should be recorded after ten minutes. decide what data to record. should be able to perform the experiment with little assistance from the teacher. July 24, 2007 Page 4 of 12

5 Students keep the balloon marked 2 at room temperature. The temperature of the room should be recorded after ten minutes. Basic students are measuring the circumference of one balloon which is placed into warm area first for 10 minutes, and then into the ice bath for 10 minutes. The instructor can measure the temperature in each setting and provide it to the students. The balloon marked 3 should be put in a warmer area for 10 minutes, such as under a heat lamp or 100 watt light bulb. Students and teachers could also think of other ways to warm the balloons (possibly near a window in the sun, a radiator, or a portable heater.) Do not put balloons in an oven. Balloons should not be heated a lot or they will pop or a student may be burned. The temperature should be recorded after ten minutes. Intermediate students may need the teacher on hand to show them how to make the measurements, but they should be able to handle them after being shown what to do. After 10 minutes, each temperature should be recorded, and the circumference of each balloon measured. Measure at the same spot on the balloon that was used previously. Measure immediately upon removing from ice bath or warm area. Do not wait. Record the information in the data table. are following the methodology they devise for the experiment. July 24, 2007 Page 5 of 12

6 Questions for students: The teacher may need to guide basic students through the thought processes involved with answering these questions. Be sure they understand the answers to each question. 1. What happened to balloon 1 in the ice bath? 2. Did any air escape from the balloon? 3. Did the density of the balloon increase or decrease? 4. What do you think happened to the air inside the balloon? 5. Did the result of your experiment confirm your hypothesis about balloon 1 in the ice bath? 6. Is your prediction supported? Or does it need to be modified? 7. What happened to balloon 3 in the warm area? 8. Did the density of balloon 1 increase or decrease? 9. What do you think happened to the air inside balloon 3? 10. Did the result of your experiment support your prediction about balloon 3 in the warm area? 11. Is your prediction supported by the data? Or does it need to be modified? can be asked to write their own questions and record their answers in their journal. July 24, 2007 Page 6 of 12

7 Intermediate students may want to discuss the answers in small groups or as a class, before recording them in their journals. The teacher may need to guide basic students through the thought processes involved with answering these questions. Let the balloons stay at room temperature for 5 minutes. Observe the balloons during that time. Then measure the circumference of each balloon again. Record the data in the table. The different groups in the class should compare their results. Results could be written on the board for easy comparison. Do the similar experiments give similar results? If there are differences, are the differences significant or trivial? If there are differences, list the possible causes. (Causes could be recorded on the board as the class suggests them.) are following the methodology they devised. Encourage advanced students to replicate their experiment several times to get additional data. Show advanced students more data from another experiment that demonstrates the same concept. can brainstorm other experiments to do that will demonstrate the same concept, and write the procedures and bring in supplies to perform the experiment. July 24, 2007 Page 7 of 12

8 The teacher may need to guide basic students through the thought processes involved with answering these questions. Discussion: What does this experiment tell you about warm and cold air masses? Which air mass would you expect to be denser (warm air or cool air)? Which type of air mass takes up more space (warm air or cool air)? Which balloon has the greatest air pressure (warm air or cool air)? Intermediate students may want to discuss the answers in small groups before recording them in their journals. After completing the experiment and discussing the results with the class, the teacher should discuss atmospheric science, including the concepts of air pressure, convection (hot air rising, cold air sinking), and wind. This leads to a discussion of thunderstorms, tornados, and hurricanes. Here is some helpful information relating storms to the balloon expansion/contraction and air pressure experiment you just performed. What causes wind? Wind is the result of horizontal differences in air can think about these questions and record their answer in their journal. can research the causes of wind, thunderstorms, tornadoes, and hurricanes on the internet. July 24, 2007 Page 8 of 12

9 pressure. Air moves from areas of higher pressure to areas of lower pressure. Differences in air pressure are caused by uneven heating of the Earth's surface. The Sun is the major source of energy for heating, and so is the cause of wind. Much of the Sun s energy striking Earth causes intense heating in the equatorial regions. This intense heat produces powerful convection in these areas. As the warm, moist air rises, it creates a zone of low pressure, clouds, and precipitation along the equator. As that warm air rises, it eventually reaches a point in the atmosphere where it can rise no higher, and it spreads outwards towards the poles. As it spreads, it cools and sinks back down to the surface at about 30 degrees north and south of the equator. This sinking air produces areas of higher pressure with drier conditions. What causes thunderstorms? The Sun warms the Earth, and the Earth warms the air above it by reflecting the Sun s radiation and by emitting radiation at longer wavelengths that our eyes July 24, 2007 Page 9 of 12

10 cannot see (infrared radiation), or by conduction in the several millimeters of air closest to the Earth s surface. Warm air rises by convection. Warm air rising through cooler air is called unstable air. The warm air rises, and at some point, condensation occurs high in the cloud. Precipitation occurs (rain and sometimes hail), and a cold downdraft forms as the rain falls. Thunderstorm formation requires three things: Moisture - to form clouds and rain. Unstable Air - relatively warm air that can rise rapidly. Lift - things like fronts, sea breezes and mountains can lift air to help form thunderstorms. What causes tornadoes? Tornadoes are the most violent type of storm. They have wind speeds of up to 300 miles per hour. Tornadoes develop from powerful thunderstorms. What causes hurricanes? A hurricane is a rotating tropical storm with organized circulation, and sustained winds of more than 74 miles July 24, 2007 Page 10 of 12

11 Resources per hour. Hurricanes develop over warm tropical ocean waters. Hurricanes gather heat and energy through contact with the warm waters. Water is evaporated from the sea, and the moisture powers the storm. The air warms and rises higher into the atmosphere. Hurricanes have spiral bands of clouds and thunderstorms that produce heavy rain, wind, and tornadoes. x.shtml Homework/Extens ion pace/gps/storms-hurricanestornadoes-thunderstorms.html edu/2004q4/211/notes_convec tion.html tml/storms2.html wister/cmp/swirl.html her/default.htm Investigate severe weather events online. Track a hurricane on a map using online data from NOAA. Instructional Tasks Accommodations for ELL Students Highlight key points in the article Reduce the number of key points these students are responsible for knowing Extend the time to complete the task Use hands-on and inquiry based activities July 24, 2007 Page 11 of 12

12 Instructional Tasks Accommodations for Students with Specific Disabilities Instructional Tasks Accommodations for Gifted Students Keep language simple Provide bilingual support for content material Assess students background knowledge Introduce one activity at a time, in small steps Break work into manageable parts Reinforce oral instructions with written instructions Graphically display an analysis of the expected task including a checklist to facilitate attention to task and organizational skills Praise and reinforce students efforts Assess informally on an on-going basis Offer choices for tasks Curriculum compacting and chunking Learning contracts Problem-based scenarios Allow opportunities for reflection and self-assessment Provide constant collaborative experience Socratic questioning Allow students to jigsaw concepts Balloon 1 (cold) Initial Circumference (cm) Temperature after 10 minutes ( o C) Circumference after 10 minutes (cm) Circumference after 5 min at room temp. (cm) 2 (room temp.) 3 (warm) July 24, 2007 Page 12 of 12