Grade Level/Unit Number: 7th grade/Unit 3 II: Unit Title: Weather & Atmosphere
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- Navigate this page:
- Below is the direct link to the AccuWeather.com video
- Explain
Explore:Ask students- What is air? Accept all possible answers. Show the 2-minute explanation of what makes up air (link below). The video summarizes the properties of air and says, “it is similar to us living on the bottom of an ocean of air because it is constantly pushing down on us. It creates pressure, and even though you cannot see air, you can see the affects of it”. It will present the characteristics of air that students may not have known. What is air made up of?-The clip is from: http://www.videojug.com Direct link: http://www.videojug.com/expertanswer/fun-science-space/what-is-air-made-up-of Ask students: What gases are in the air? They probably will quickly answer “oxygen,” because we need it to breathe, and carbon dioxide, because plants convert it into oxygen. Introduce them to the word atmosphere - a blanket of air that surrounds the earth. Air is made up of 78% nitrogen, 21% oxygen and 1% trace gases (the 1% is a combination of several gases). We breathe air that is 21% oxygen, and we require oxygen to breathe. (You might think that breathing 100% oxygen would be good for us, but actually it can be very harmful. It can cause nausea, dizziness and chest pains.) The atmosphere is divided into distinct layers. Introduce students to the main 4 layers: troposphere, stratosphere, mesosphere and thermosphere. Allow students to complete the 4 layers of the atmosphere brace map. The 4 layers are listed to the left and on the lines to the right they should list two properties or characteristics of that layer. At the bottom there is a square to draw a picture so they remember something about each layer (attachment 2). They can use their text or research materials to fill in the blanks. Go over the answers as a class and allow students to keep them as notes or complete as a graded assignment. The upper layer of the atmosphere, the exosphere, is not included in the brace map; it is the layer beyond the thermosphere that includes space. Sample student answers for the brace map: troposphere- layer nearest Earth, where weather occurs and airplanes fly, temperature drops as altitude increases, where people live, known as lower layer of atmosphere stratosphere- where most jets fly, where the ozone layer is found, atmosphere is drier, ozone here absorbs and scatters UV radiation mesosphere- called the middle atmosphere, it is the coldest layer of the atmosphere, radio waves are reflected to Earth and meteors burn up in this layer, temperature continues to decrease with altitude thermosphere- temperatures can be very hot in this layer, known as upper atmosphere, temperature increases with altitude- it is the hottest layer, aurora lights occur here, may also be called the ionosphere The website -AccuWeather.com Videos- has a variety of weather related clips. Once you have accessed the site, choose a weather video from the segments at the bottom of the screen. Below is the direct link to the AccuWeather.com video :http://www.accuweather.com/media-player.asp?partner=accuweather&myadc=0&traveler=0&vidcode=undefined&issub=undefined&subindex=undefined&adfirst=undefinedDay 4To check for understanding thus far, ask students the following agree or disagree questions. You can make it more challenging by having them correct the statements they disagree with. Post the word AGREE on one side of the room and the word DISAGREE on the other. Everyone starts in the middle of the room. After you ask the question, instruct students to move to the side of the room that supports their opinion. No one may stay in the middle. Students can use their brace map for help if needed. 1. We live in the troposphere. (AGREE) 2. Radio waves travel in the mesosphere. (AGREE) 3. There are 7 main layers of the atmosphere (DISAGREE- there are 4 main layers in the atmosphere) 4. The exosphere (layer 5) is commonly called space. (AGREE) 5. All weather occurs in the stratosphere. (DISAGREE- weather occurs in the troposphere) 6. The hottest layer of the atmosphere is the troposphere. (DISAGREE- warmest layer is the thermosphere) 7. The mesosphere is the coldest layer of the atmosphere. (AGREE) 8. The ozone is found in the thermosphere. (DISAGREE- ozone is found in the stratosphere) 9. Temperature gets colder as you move higher away from the Earth. (AGREE) 10. The main component of air is oxygen. (DISAGREE- it is nitrogen) Explain:Reinforce the concept of the layers of the atmosphere. Students can complete the Modeling Earth’s Atmospheric Layers scale activity. (attachment 3) Students can complete it in individually in class, in small groups or as a homework assignment. A grading rubric is included as attachment 4. You can easily assess what they learned on the previous day’s lesson. Students or groups will need butcher paper (bulletin board), about 3 square feet and coloring utensils. Day 5When discussing the layers of the atmosphere, you might have mentioned the following two statements – As altitude increases, air pressure decreases. As altitude increases, temperature decreases. This means, as you go higher there is less pressure. As you go higher it also gets colder. To show the effect this directly has on the body go to unitedstreaming.com and search: Science Investigations: Life Science: Investigating Human Biology Show the clip- Respiration at high elevations (8 min)
After the video, discuss: Why is the air thinner at higher elevations? Because there is less air pressure and the molecules are spread farther from each other. When at higher elevations you can take the same amount of air in with one breath, but you have fewer oxygen molecules in that breath. This can lead to altitude sickness.
2. Where is air pressure greatest? A 3. Where does air have less mass? B 4. Where are oxygen molecules farther apart? B 5. Where is the temperature the coldest? B 6. Where would air seem the heaviest? A 7. Where might a hiker have the most difficulty breathing? B 8. If air pressure is constantly pushing down why doesn’t it crush things such as a tin can or hollow objects? Because the air is pushing in all directions and is balancing out. 9. As you move toward sea level, from B to A, what will happen to the air pressure and the air temperature? The air pressure and temperature will both increase and become greater. For additional practice with the concepts of altitude and temperature, have students solve the following math problems. As altitude increases, temperature decreases. At higher altitudes the air is thinner and colder than at lower altitudes. The air drops 3º for every 1,000 feet of altitude above sea level. (This rule is not accurate for altitudes above 40,000 ft) Calculate the temperature at each altitude given. Go over the chart to check that students calculated the correct answer. (answers are rounded)
For a follow-up, ask students to write a summary comparing the effect that altitude has on air pressure. Make sure to explain what each word means so that others can fully understand the explanation. Each written word is worth 10 cents. While explaining their answer they are to spend between $2.60-$3.00. Attachment 5 contains a piggy bank for them to write their summary inside. Directory: file -> view view -> Western Europe after wwii view -> Author study: paul fleischman view -> Qpa1 7ela study Guide view -> Arctic Oil/Gas Neg view -> November 1970 Approximately 150,000-500,000 deaths Bhola Cyclone Bangladesh view -> Grade Level: 6 Unit of Study: Caribbean glce view -> Citation: Duffield, Katy view -> Table of Contents Lesson # view -> Chinese Wind Energy Disad Download 1.54 Mb. Share with your friends:
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raw the mountain picture on the board or overhead when discussing the questions.