Catastrophic Events
Catastrophic Events
Part 1
Lesson 2
Focus Question: What is the effect of sunlight on the Earth’s surface?
Learning Target:
· I know heat can be transferred by radiation, conduction, or convection.
· I know solar radiation, or energy from the sun, is a major source of energy for weather phenomena.
· I know the surfaces of the earth and the atmosphere both absorb and reflect the sun’s radiant energy; absorbed energy is converted to heat and can be radiated back into the atmosphere.
· I know temperature is an indication of the amount of heat energy in a solid, liquid, or gas.
· I know the composition, color, and moisture content of a material affect the rate at which it absorbs or reflects solar energy.
· I know the atmosphere, which has different properties at different altitudes, is a mixture of nitrogen, oxygen, and trace gases, including water vapor.
Student Objectives:
· Observe and record the rates at which equal volumes of soil and water heat and cool.
· Graph and analyze the heating and cooling rates of soil and water.
· Explain what happens to energy from the sun when it reaches the earth.
· Read and interpret a data table.
· Describe the atmosphere and its layers.
Getting Started:
1. Your teacher will review your homework with you and your class. Following the questions on Student Sheet 2.1, discuss what you know about thunderstorms; where typhoons, hurricanes, and cyclones are likely to form; and the similarities and the differences between tornadoes and hurricanes.
2. What do you think causes storms? Discuss this with your class.
3. Brainstorm with your class ways you might investigate how soil and water heat and cool.
Inquiry 3.1: Investigating Rates of Heating and Cooling
1. Review with your teacher how to use a stopwatch and digital thermometer.
2. As a class, go over Procedure Steps 5 through 13. Observe as your teacher demonstrates the steps needed to complete the investigation.
3. With your class, review the Safety Tips for this inquiry.
4. Review Student Sheet 3.1a: Testing the Heating and Cooling Rates of Soil and Water as your teacher discusses it.
5. Think about this investigation as if it were a race or a test between equal volumes of soil and water. Under Question 1 on the student sheet, record all the things you think you will need to keep the same for the beakers.
6. Pick up your group’s remaining materials. To set up a fair test, get equal volumes of soil and water from the distribution center.
7. Set up the materials as shown in Figure 3.1. Insert each thermometer approximately 2.5 centimeters (cm) into the soil or water I each beaker. Do not allow the tip of the thermometer to touch the bottom of the beaker. Use the small hole in the cardboard to hold each thermometer upright. Turn on the thermometers.
8. Allow the thermometers to sit in each beaker until the temperature readings no longer show any sign of changing.
9. While you are waiting for the temperature readings to stop changing, make some predictions. What do you think will happen to the temperature of the soil and the water when you turn on the lamp? What will happen when you turn off the lamp? Why do you think this? Record your predictions under Questions 2 on Student Sheet 3.1a.
10. Do not turn on the lamp yet. After the readings on the thermometers have stabilized, record the temperatures of both the soil and the water in Table 1 on Student Sheet 3.1a, across from 0:00 minutes under the column labeled “Heating”.
11. Turn on the lamp.
12. Start your stopwatch. Read the temperature of both materials to the nearest 0.1 C every minute for 10 minutes. Record your data in the table.
13. At the end of 10 minutes, turn off your lamp but let the watch keep running. Quickly record the 10-minute temperature for soil and water in the Heating columns. Record the same number across from 10:00 minutes at the top of the Cooling columns. Continue reading and recording the Cooling temperature for soil and water every minute for 10 minutes.
14. When you finish, clean up.
a. Turn off the digital thermometers.
b. Dispose of the water from you beaker in a sink or bucket.
c. Do not throw away the soil. Pour it into the empty container set our by your teacher, where it can cool.
d. Return your materials to your plastic box for the next class.
e. Your teacher will tell you where to put your lamp.
15. Complete Student Sheet 3.1a. Calculate the overall change in temperature of each beaker during heating and cooling. For the Heating columns, subtract the first temperature (0:00 minutes from the last temperature (10:00 minutes). For the Cooling columns, subtract the last temperature (20:00 minutes) from the first temperature (10:00 minutes). Give your answers to the nearest 0.1 C.
16. How might you plot your data on a graph so it is easy to read? Before you begin, discuss your ideas with the class.
17. Work with your group to create one graph on an overhead transparency. While you do, consider these questions:
a. What title will you give your graph?
b. How will you label each axis to show the temperature and time changes?
c. What will be the first number on each axis? How will you space the numbers on each axis?
d. What techniques will you use to make the graph more readable?
18. Review your group’s completed graph with the class or with another group. Analyze the graphs using the questions in Procedure Step 17. How easy are the graphs to interpret?
19. On your own, graph your group’s data using graph paper and the tips you discussed with your teacher and the class. Title your graph.
Reflecting on What You’ve Done
1. Answer these questions. Then discuss them with the class.
a. How would you describe the heating and cooling rates of soil and water in this investigation?
b. Which material held its heat longer?
c. What factors may have influenced your results?
d. Reread the Introduction to this lesson, Can you explain now why concrete feels hot under your feet in early summer, while water in a pool feels cold?
e. On the basis of your investigation, how do you think oceans absorb and hold heat? How do you think the temperature of the ocean compares with the temperature of the land nearby?
2. Discuss “The Source of Earth’s Heat”, on pages 31-33, which you read for homework, with your class. Review the questions at the end of the reading selection.
3. Complete Student Sheet 3.1b: Interpreting a Data Table. You should also read “The Atmosphere: A Blanket of Air,” on pages 34-36.
4. Read “Weather Versus Climate.” Look ahead to Lesson 4 & 5. In these lessons, you will investigate how the uneven heating of the earth’s surfaces affects weather in the earth’s atmosphere. (See selected readings for questions to answer).