Stephanie J. Sheehan
Climate and Weather
For the first section of this unit, the students will read, study and discuss information about Ghana’s climate and weather. After the information has been discussed, reading comprehension questions will be modeled, discussed and answered in writing. The reading will be teacher-created, as will the written response questions. The reading material will be created at a level the students can read together with teacher and/or pee r support. The written response questions will match the literacy curriculum focus with the content on Ghana. A sample may be found in Appendix 2.
Secondly, the students will compare and contrast the weather and climate of Ghana with their own Connecticut weather through discussions and journal writing. They will learn why the climate is different through hands on demonstrations and experiments. This section will address the science performance standards for scientific inquiry numbers 1-7.
In order to understand how the sun’s heat is transferred around the Earth, the students must first understand global rotation, revolution, and conceptualize the Sun’s radiation of the Earth. Therefore, the students will observe a demonstration of the earth’s rotation and revolution around the sun using a globe and a yellow ball. Then, the students will draw and write about this in their science journals, and finally act out the movement of the earth as it moves around the sun. The students will observe as a dot is placed on the globe and the globe is moved around the sun while rotating on a tilted axis. They will observe how the sun’s rays reach each hemisphere at different times of the year, but the majority of the sun’s energy remains within the tropical area all year long.
Once the students understand how the sun’s energy heats the regions of the earth, they will be ready to begin a series of four science experiments which are designed to help them understand convection and how it affects Ghana’s weather.
First, the students will have an opportunity to share what they think they know about warm air and cold air and how it moves. They will read and research to learn that warm air has less density than cold air. Then they will have opportunities to make predictions and experiment with objects of varying densities to see what happens to them when placed on a balance scale. This first experiment will allow them to create an accurate hypothesis for the second experiment.
The second experiment will allow the students to observe convection in water, which will be conducted as a science fair project. The students should have enough knowledge about density to hypothesize that hot water is lighter than cold water, and therefore should move upward within colder water. Then, they will observe as food coloring is used to show the warm water currents rising and falling within a large container of colder water. They will measure the temperature of the water in the large jar and the small jar and repeat the experiment with water at several temperatures. They will use their science journals to record predictions, pictures and written observations, and conclusions. The students will then read teacher created text (at shared reading level) which will explain how convection within the ocean creates patterns that are important to global weather. The students will write and draw to show what they’ve learned. See attached lesson plan.
Convection Experiment (adapted from 2008 Home Training Tools)
Objectives: Develop prediction and observation skills, learn that hot water is less dense and therefore lighter than cold water, so it rises above cold water. Observe convection currents within water and record the results. Students will use their understanding of the results to visualize how convection affects the ocean water.
Materials
: large clear container, a small clear container with a flat bottom, plastic wrap, knife, food coloring, thermometer, cm ruler, rubber band
Procedure
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1. First, fill a large bucket with cold tap water and a small jar with cold tap water.
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2. Measure the temperature of the cold water in the bucket and the small jar.
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3. Then, color the water in the small jar so it may be observed.
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4. Cover the small jar of water with plastic wrap and secure it with a rubber band.
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5. Create a hypothesis about what will happen when the small jar of water is opened and the water is allowed to escape.
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6. Carefully lower the small jar into the large bucket of water and cut a hole in the plastic wrap to allow the colored water to come out into the clear water.
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7. Use a ruler and a timer to measure the amount of water that has risen within 10 second intervals.
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8. After the colored water appears to stop rising, measure how many centimeters the colored water has lowered within the small container.
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9. Record observations with pictures and words in the science journal.
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10. Repeat several times, filling the small jar with water at different, warmer temperatures. Record the temperature each time.
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11. Follow science fair guidelines by creating a graph for the information.
A third experiment will allow the students to observe how air movement is affected by warmth and cold as well. They will see how warm air moves straight up in a draft free setting, and then creates a high pressure zone and low pressure zone. The teacher will heat a baking tin full of sand and place the heated tray next to a tray of ice. Students will watch as smoke from a lighted match moves from the high pressure zone above the ice, to the low pressure zone above the heated sand. This will allow the students to see how wind is created. The students will then continue to learn how air pressure creates wind, as well as other types of weather. See attached lesson plan.
Observing Air Movement (Adapted from 2008 Home Training Tools )
Objectives: Students will develop prediction and observation skills, learn that hot air is less dense and therefore lighter than cold air, so it creates less air pressure than cold air. Students will observe as a small high pressure zone is created with cold air that will move into the lighter, low-pressure warm air, thereby creating a tiny wind current.
Materials: two large baking tins, sand, ice, small candle, lighter, oven, oven mitt, draft free table.
Procedure
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1. First, create a draft-free display space with a 3-walled study carrel desk or cut cardboard box.
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2. Pour sand into one of the baking tins and heat in the oven for about ten minutes.
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3. Set the hot tin on an oven mitt on the draft free table.
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4. Hold a candle over the hot sand in what is now a low pressure warm air zone. Have students predict what the air will do over this hot sand. They should predict that warm air moves up, since it is light.
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5. Light the candle and blow it out so that the smoke will show the movement of the warm air.
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6. Next, fill the second tin with ice cubes and set it next to the hot sand. Ask the students to predict what will happen to the air between the two tins.
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7. Light a candle right between the two tins, touching the edge of the ice tin. Blow it out so that the students may observe the movement of the air through the smoke.
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8. Ask students to deduce why the smoke flows away from the ice and toward the heated sand.
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9. Have students draw and write about this in their journals. Then have them draw the earth and predict what happens when the warm air from the tropics meets the colder air of the polar regions. Which way will the wind blow?
Finally, the students will experiment with movement to see how the Coriolis Effect creates movement of Earth’s air east and west as it moves vertically. The students will venture into the yard in groups of 4 or 5 students and create circular movement with their bodies. They will measure the distance traveled by the center and the outer edge of the circle to observe that the person on the outer circle moves farther in the same amount of time, or faster than the person in the center. See attached lesson plan.
The Coriolis Game
Objectives: Students will create, observe and measure the Coriolis Effect, allowing them to understand the eastward and westward movement of the earths prevailing winds. They will make observations verbally and in writing and drawings.
Materials
: Students, 2 yard sticks per group, measuring tape, timer, chalk or something to mark the ground with.
Procedure:
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1. One student will stand on a designated, marked spot on the ground, holding a yard stick in on hand by his side.
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2. A second student should hold the other end of the yard stick with the opposite hand held at his side and a second yardstick in the other hand.
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3. A third student should hold the opposite end of the second stick in one hand and a soft ball in the other.
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4. A fourth student or a team of two students should mark the spot where the second and third child stand and set the timer.
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5. The three students holding the stick should begin moving counterclockwise as the timer begins. They should be careful to stay in a straight line by holding the yardsticks steady.
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6. After 10 seconds, the measuring team should measure the distance traveled by the first, second and third child.
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7. Students will discuss and record their observations, then look at the globe to relate the concept to the air on the surface of the earth at various latitudes.
Follow up: Two students could repeat this movement on pavement, and draw a straight line with sidewalk chalk along the yard stick as they move around in a circle. When they stand up, they will see that their “straight line” has become a curve.
After participating in all four experiments, the students will read, write about and draw information about how global wind patterns affect Ghana’s climate as a result of its location within the tropics. The students will look at pictures of wind patterns across the globe and relate these patterns to what they learned about convection. The students will learn how tropical winds create rainy and dry seasons near the equator, rather than the drastic differences in temperature between seasons that we experience farther from the equator. They will understand how the winds move northeast bringing wet air during the wet season and southwest during the harmattan season.
The students will also have a chance do several more hands on activities to bring the subject more to life for them. They will each plant two seedling plants and observe what happens when very little water is available by watering some plants every day and some only once a week. The students will observe and write about their plants in their science journals. Furthermore, they will keep charts, recording the weather in Connecticut and the weather in Ghana, especially the temperature and rainfall. They will write comparisons and make graphs to show the patterns of the weather in each location. The students will create wind catchers and act out the movement of the wind across the equator. They will also draw wind patterns on maps of the world. They will demonstrate their learning by creating speeches or written papers explaining how and why the seasons are different in Ghana compared to the northeast United States. At this point, the students will write letters to invite students and parents of our school community who are from Ghana to speak to them about the weather and climate of Ghana. They will prepare questions for our guests and write journal entries afterwards, as well as thank you letters.
In addition to completing science experiments that will help the students understand how and
why
the climate and seasons are different, the students will also write pen pal letters describing the weather and seasons they’ve experienced. The class will be paired with students from Ghana who are studying the United States, through a web service called Epals. They will tell their new friends what they have learned about Ghana so far. They will ask their new friends to elaborate on how their experience has been similar or different from what they’ve learned in our classroom. The students will then ask questions to find out more about the students’ experiences in Ghana.
The Food Resources of Ghana
For the second section of the unit, the students will learn how the wind patterns and seasons affect the nutritional resources of people in Ghana. This will address the New Haven Science Curriculum Standard A24: “Describe how people in different cultures use different food sources to meet their nutritional needs.” The students will learn about the natural resources of the area and how they are affected by the climate and seasons. During this section of the unit, students will compare and contrast foods they eat with those eaten in Ghana and sort the foods according to the food pyramid. They will also participate in taste tests of some of the vegetables grown in Ghana
First, the students will conduct research in the library to find out what the food staples are in the United States. They will then research and write about the climate and weather conditions necessary to grow these resources. They will then compare the food staples of the United States with those of Ghana. They will be able to explain how the climate of Ghana supports the staple foods grown there.
Secondly, the students will use the internet to find pictures of the foods found in the United States and those found in Ghana. They will cut out the pictures, label them, and create a display showing the foods of the United States and of Ghana. They will explain the similarities and differences within a speech to the class and/or in writing.
The students will continue their research, as necessary, in order to classify the foods of Ghana into the categories of the food pyramid. Students will create giant posters with the food pyramid and glue pictures of different meals onto the poster. They will present food pyramids for both the United States and Ghana. As a follow up, students will create Jeopardy questions about the foods of Ghana and challenge their classmates.
As a culminating project, students will create presentations on the foods of Ghana and their nutritional content. They may choose to present cooking demonstrations, taste tests, posters, or dioramas
along with
a written report.
