Name

Date Per

Heating of Land versus Water

The effect of the sun's radiation depends on numerous factors including sun angle, altitude, latitude, cloud cover, surface color and composition. Of these, the difference in heating of land versus water is most the most prominent given the irregular arrangement of continents and oceans in the northern and southern hemispheres, and the way each absorbs and stores energy.

Question: Which material will heat the fastest?Why?

Hypothesis:

Experimental Objectives:

  • Record and graph temperatures
  • Compare the absorption and radiation of heat for "land" and "water."

Materials:

  • 3 thermometers
  • 3beakers
  • laboratory lamp
  • clamp for lamp (if necessary)
  • stopwatch or clock
  • water
  • sand or soil
  • graph paper
  • physiographic map of the world

Procedure:

  1. Place a thermometer in eachbeaker so that the bulb of the thermometer is covered with 0.5 cm of either sand or soil.
  2. You will have to hold the thermometer in place for the water. DO NOT allow the thermometer to touch the bottom of the beaker.
  3. Set the beakers under the lamp so that the surface of each material is equal distance from the bulb.
  4. Record the initial temperature of each thermometer on the data table.
  5. Turn the lamp on and record the temperature of each substance every 2 minutes for 10 minutes. Be careful not to move the thermometer when taking your readings.
  6. Turn the light off, and continue to record the temperature for another 10 minutes.
  7. Clean up your lab station. Dispose of materials as per your teacher's instructions.
  8. Create a multi-line graph of temperature vs. time using a different color line for each substance. Place the independent variable "time" on the x-axis, and the dependent variable "temperature" on the y-axis. Title your graph "Heating and Cooling of Different Surfaces."
  9. Answer the questions below.

Data:

Heating and Cooling of Different Surfaces
Heating / Cooling
Time (minutes) / 0 / 2 / 4 / 6 / 8 / 10 / 12 / 14 / 16 / 18 / 20
Soil Temp (oC)
Sand Temp (oC)
Water Temp
(oC)

Analysis and Conclusion Questions:

  1. Study the lines on the graph. Which substance heated the quickest? Which substance heated the slowest?

______

______

  1. Considering the terms absorption and radiation, which substance absorbed the most heat, and which one radiated the most heat? What part of your graph did you look at to acquire this information?

______

______

  1. How does color affect absorption and radiation?

______

______

  1. Look at a physical map of the world. How does this lab model the heating and cooling of land versus water? Explain.

______

______

  1. In what ways was this lab a good model for what actually occurs? In what ways was this lab an inadequate model for actually occurs?

______

______

© 2011 Simmons Summer Institute. Missy Holzer, Ruth Starkins, Kelley DeRosa

Teacher’s Notes

Heating of Land versus Water

Preparation:

Supplies for this lab can be stored and pulled out each year. No preparation required.

Materials:(supplies for each team of 3 or 4)

  • 3 thermometers
  • 3 aluminum pie plates
  • laboratory lamp with 100 W bulb
  • clamp for lamp (if necessary)
  • stopwatch or clock
  • water
  • light colored sand
  • soil
  • graph paper (1 per student)
  • physiographic map of the world

Important Information:

1.Students may need assistance in setting this lab up so that all variables controlled. Circulate around the classroom to ensure that they are following the procedure correctly.

2.At the conclusion of this lab discuss ways in which this lab can be repeated to test other variables.

Answers to Analysis and Conclusion Questions:

1.Study the lines on the graph. Which substance heated the quickest? Which substance heated the slowest?

Student answers may vary depending on their results, but it would be expected that soil would heat the fastest, and water heat the slowest.

2.Considering the terms absorption and radiation, which substance absorbed the most heat, and which one radiated the most heat? What part of your graph did you look at to acquire this information?

Student answers may vary depending on their results, but it would be expected that soil would absorb and radiate the most heat. They would look for the line on their graph with the greatest slope during the heating and cooling periods.

3.How does color affect absorption and radiation?

Darker colors absorb and radiate more heat.

4. Look at a physiographic map of the world as well as Figure 1 and Figure 2. How does this lab model the heating and cooling of land versus water? Explain.

Student answers may vary, but they should mention that the isotherms bend the most over land.

5.Identify a location in the middle latitudes of a continent that has a large annual temperature, and identify a location in the middle latitudes of a continent that has a small annual temperature range. Explain why you choose each of these locations.

Student answers will vary, but they should select an inland location for a large annual temperature range, and a coastal location for a small temperature range.

6.In what ways was this lab a good model for what actually occurs? In what ways was this lab an inadequate model for actually occurs?

Student answers will vary.

References:

Pictures from:

© 2011 Simmons Summer Institute. Missy Holzer, Ruth Starkins, Kelley DeRosa