Heating the Earth Activity:


You will learn how different materials absorb and lose heat at different rates.  


You will need:

3 plastic containers                    3 thermometers

A stopwatch                               Some water

Some potting soil                       Some sand

A heat lamp


  1. Fill the three containers half full- one with water, one with sand, and one with potting soil.

  2. Place a thermometer into each container.  Make sure the thermometer is straight upright and that the bulb is completely covered.  

  3. Place the containers under the heat lamp so that each gets the same amount of light.  Make sure that the thermometers are upright and NOT receiving any direct light.

  4. BEFORE you turn the light on, record the starting temperature of each container and record in the “Initial T” box.

  5. Turn the light on and measure the temperatures every 5 minutes and record the readings.  After 20 minutes, turn the light off and record the cooling temperature. Ater 5 minutes of cooling, check the temperature, then after 10, then after 15.

Data chart:



Initial

    Warming Up

    Cooling Down


Time

    0

    5

    10

    15

  20

    5

   10

    15

    

Water










Sand










Soil











On a sheet of paper, create a triple line graph.  Use a different color pencil for each substance.  Be sure to make a color key for your graph.  Ask for help as needed.


Questions:

  1. What can you conclude from your observations? (Explain what you observed about the heating and cooling of the different materials)



2.  What do these results teach you about how the Earth heats and cools?  


3.  How do you explain why water seemed to heat and cool at a different rate than soil or sand?


4.  Think about it:  What do you think would happen if the Earth were 70% land and only 30% water?  How might our climates be different?