Grade Level/Unit Number: 7th grade/Unit 3 II: Unit Title: Weather & Atmosphere
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- Navigate this page:
- Explore
- Isotherm
- High Pressure
- Day 8 (optional) 2 nd Extension- Focuses on the computer skills test
- Title Activity- Worst Weather in US History
- Students should NOT SAVE the database after answering the questions
Day 1Engage: Begin the unit by having students write down (on paper or the board) as many specific features as possible of the weather conditions in your city that have occurred in the last week or so. Encourage them to (if necessary) to mention temperature changes, cloud types, any precipitation, wind direction, and wind strength. Assess prior knowledge of weather maps by passing out a “teacher, newspaper or Internet generated” map with some randomly drawn fronts, isobars and isotherms. At this point, some type of brainstorming session / peer work would be good. Have the student pairs/groups attempt to identify different features such as fronts, precipitation, approaching major storms, isobars and isotherms and weather conditions found on those maps. Day 2Explore: Have the students work on the map activity located at http://www.srh.noaa.gov/jetstream/synoptic/wxmaps.htm. The link will take them to a page entitled “How to Read Weather Maps.” The information in this section will be referenced in the Elaborate section of this unit. Go to the bottom of the page and click on “Learning Lesson: Drawing Conclusions.” Have student complete these activities. If you do not have Internet access, the maps, directions and solutions are located at the back of this unit (Attachments 1-6). The first attachment is a student handout or can be made into an overhead; the second copy contains the actual directions.
Day 3Explain: Weather fronts are air masses of different types that collide with each other. The boundary where the air masses collide may be relatively narrow (10s of km) or rather wide (100s of km). Based on which air mass is moving / not moving determines the specific type of front. Each frontal type has particular characteristics that can be experienced on the ground and represented on a weather map. A couple of definitions will also help with the explanation of the weather map: Isotherm – contour lines on a map that connect areas of equal temperature. Isobars – contour lines on a map that connect areas of equal atmospheric pressure. Isobars and isotherms are somewhat “fluid” measures, so their lines on a map tend to be curved and irregular. These measures often are on a particular scale (every 10o C, or every 20 mb) representing a gradual change across a geographic region. High Pressure – region of the greatest atmospheric pressure. Winds around a high-pressure system circulate in a clockwise rotation termed “anti-cyclonic.” Low Pressure – region of the lowest atmospheric pressure. Winds around a low- pressure system circulate in a counter-clockwise motion termed “cyclonic.” To help students remember “cyclonic,” remind them that low pressure systems can be associated with large/violent storms and the term “cyclone” is used for both tornadoes and hurricanes (Pacific), both of which rotate in the counter-clockwise direction. One frontal type is a cold front. A cold front is a mass of “colder” air that moves under a mass of warmer air at a particular location. Cold air masses tend to move quickly and are characteristic of rather abrupt changes in local weather. As a cold front moves into an area, it pushes the warmer air mass upward at a fairly steep angle. The movement of warm (typically moister air) upward can cause violent storms to occur along the front. The appearance of cirrus clouds in the upper atmosphere can often be used an indicator of an approaching cold front. Storms may occur ahead of the front as well as along the frontal barrier, but skies tend to clear rather quickly after the passage of a cold front. Strong lines of thunderstorms are characteristic of the passage of a cold front. On the weather maps cold fronts are represented as a line of triangles. The triangles are often colored blue or green (cooler colors), with the point of the triangle signifying the direction of movement. Warm fronts move slower and tend to be less dramatic than cold fronts. Warm air, which is naturally less dense, rises slowly above an area of cooler air. The passage of a warm front also causes precipitation, but more typically these areas experience light to moderate continuous rain. The lighter rain is in contrast to the severe thunderstorms associated with the passage of a cold front. Cloud formations with the passage of a warm front tend to have a greater concentration of mid-level stratus and cumulus clouds. The formation of fog is also associated with the passage of a warm front. The formation of fair weather occurs more gradually with the passage of a warm front. Warm fronts appear on the weather map as a line of semi-circles (often red in color), with movement signaled by the leading edge of the circle. A third type of front is a stationary front. In a stationary front, the moving air mass (warm or cold) does not contain sufficient energy to move the existing air mass. Consequently, what happens is that the front tends to move rather slowly out of a region. Cold fronts often “stall” along the coast of North Carolina as they lose energy. A stationary front will often cause precipitation in an area for extended periods of time. Eventually, a new air mass will move in and replace the stationary front. Stationary fronts appear on the map as a line of alternating triangles and semi-circles that face in opposite directions. Wind patterns are often parallel on both sides of the front. The fourth frontal type is an occluded front. In an occluded front, the faster moving cold front catches and overtakes an existing warm front. The denser cold front forces itself under the existing warm front causing heavier amounts of precipitation to fall (inches of rain or snow). Due to the hybrid nature of the occluded front, weather patterns at the beginning of its formation are similar to those of a warm front. Occluded fronts appear as a line of alternating triangles and semicircles facing the same direction. Weather patterns in the Unites States most often move from west to east. Therefore the weather to one’s west (northwest or southwest) is the precursor of what one should expect. Severe weather events like tropical storms vary from this pattern and move from east to west. Additional Internet resources covering this topic include: http://ww2010.atmos.uiuc.edu/(Gh)/wx/surface.rxml http://www.mohonasen.org/staffdev/weather5/weathermaps.htm Pass out the vocabulary chart (attachment 7). Either assign or ask students to select 2 or more of the vocabulary words just explained and complete the chart for additional vocabulary reinforcement. Day 4Elaborate: Remind students of the various weather conditions that you have previously discussed - humidity, storms, drought, flood, tornado, tsunami, hurricanes . . . and provide discussion time to recall characteristics of each. Ask: Why do we study weather conditions? (to monitor changes, predict occurrences & evaluate air quality ) How do we study weather conditions? (gather data- temperature/humidity/air quality/air pressure) What instruments do scientists use to study weather or climate? (thermometer, barometer, satellite imagery, anemometers, radar) How do meteorologists communicate their weather research to the public? (by weather maps, news reports, diagrams, weather alerts…..) How are storms such as hurricanes named? (accept all answers) How are storms such as hurricanes and tornados measured? (by intensity) A meteorologist is an individual with specialized education who uses scientific principles to explain, understand, observe or forecast the earth's atmospheric phenomena and/or how the atmosphere affects the earth and life on the planet. Meteorologists and other people with a need for more detailed information about the weather (pilots) utilize a more complex system of map details to forecast the weather. The type of data used by meteorologists includes barometric pressure, wind speed and direction, precipitation, cloud cover, dew point and current temperature. Have the students complete the activity located at http://radar.meas.ncsu.edu/education/saer/aer_summer_00.html. Similar symbols and explanations are located on attachments 8-11. If this web link is unavailable, use attachments 8-11 in cooperation with the weather data from several cities to build their own map. Sample symbol chart: 
(chart adapted from Carolina Academic Press) Day 5Meteorologists use symbols to easily convey the data they collect. It gives a visual that can easily be looked at and interpreted by others. They also keep track of storms by naming them. Students probably do not realize that there is a method to categorizing and naming storms. To reinforce storms, how they form and how they are named, students will use a computer and the internet to answer the questions to the Internet Scavenger Hunt (attachment 12). This should take one class period. The websites are listed above the questions. A copy of the answers is included as attachment 12- answers. (To make the websites easier to access, go to ikeepbookmarks.com and create an account for yourself. This will allow you to create a folder with all the links, so students can easily access and maneuver between sites.)
Day 6Evaluate: Return the students to their original groups/pairs (as in the engage section of the lesson) and give them a new set of “teacher/Internet generated” weather maps. Students should write down as many new features they can recognize, and should be able to infer what the precipitation should be, like around the different fronts. Using the weather data from your school and other cities over the past five or more days, draw the appropriate weather symbol for each day’s readings (samples attachment 13).
to know the answer to the question to try to get tic-tac-toe yourself also block the other person from getting tic-tac-toe first. Day 7Extension: As part of any weather forecast, meteorologists utilize satellite imagery to analyze and explain the upcoming weather. Students can also learn to conduct a basic interpretation of weather from satellite imagery. Infrared images (IR) are some of the more common images available through most weather websites. The IR sensors aboard most satellites measure the temperature of the land, sea surface, and the tops of clouds. Low clouds, which are relatively warm compared to high clouds, appear dark gray (gray scale calibration), while high cloud under the same parameters appear white due to the colder temperatures. An additional way to explain the cloud patterns is with color-enhanced IR. In the case of color-enhanced IR, higher clouds appear in green, yellow, orange or red based on their height. Colder objects are brighter and warmer objects are darker. In the same way, water vapor (WV) images also help meteorologists predict the upcoming weather. Bright and colored areas indicate high water vapor (moisture) content (colored and white areas indicate the presence of both high moisture content and/or ice crystals). Black and brown areas indicate little or no moisture present. WV imagery is useful for both determining locations of moisture and atmospheric circulations. Because IR measures heat differences of different objects, it can be used to help explain energy transfer throughout the atmosphere. Conductive circulation allows for warm air to rise up into the atmosphere (often carrying moisture). As the moist air rises, condensation occurs and clouds form. In intense convection situations, large cumulonimbus clouds can tower several miles into the air. These large clouds are the harbingers of extreme weather. With extreme weather, there is a movement of energy back to the Earth in terms of rainfall and wind intensity. Cloud height correlates to the amount of potential energy, and translates into rainfall amounts and wind velocities. To demonstrate the link between satellite imagery and weather intensity, have students complete the Satellite Imagery Project (attachment 15). This assignment focuses on hurricanes and helps students relate weather strength with energy transfer as can be seen in satellite imagery. It would helpful to review a few satellite images with students before they begin the project. Day 8 (optional) 2nd Extension- Focuses on the computer skills test Visit the following website: http://ncdesk.ncsu.edu/ncdesk/ It is designed to help students become more proficient on the NC computer skills test, which is given in the 8th grade. The following activity can be used with NC desk as a way to incorporate practice and computer literacy. After you visit the website you will need to go to download the current version. Title Activity- Worst Weather in US History Review vocabulary words and definitions prior to the lesson such as: sort database record field text ascending order descending order Pass out a copy of the Worst Weather in US History Handout (attachment 16) Students will need access to computers and NC Desk will need to be loaded on all of them. Students can work individually, in pairs or you can present it to the class and work on it together. The answers are included as attachment 17. Students should NOT SAVE the database after answering the questions. 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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