Objective

Students will take temperature readings in different locations and explain what causes the atmosphere to heat up in some places more than others.

Materials

• Meter stick
• Thermometer
• Masking tape
• Heat and Temperature Data sheet
• Clipboard

Procedure

1. Ask students if they’ve ever worn black clothing on a hot summer day.  What happens?  What happens when you try to walk barefoot on an asphalt driveway in the summertime?  Why doesn’t the snow melt when the sun shines on it on a clear winter day?  Explain to students that color and texture affect the behavior of light energy from the sun as it reaches the surface of the earth.
2. Break students into pairs or teams of 3 or 4.  Each team will experiment to find out how temperature and texture affect incoming sunlight energy.
3. Give each team a meter stick, a thermometer, masking tape, Heat and Temperature Data sheet and a clipboard.  Have students tape the thermometer to meter stick so the bulb is 10 cm above the bottom of the stick.
4. As a class, brainstorm different locations that could be measured that demonstrate differences in color and temperature.  Encourage students to think of areas that represent opposite ends of the spectrum, such as asphalt for black, concrete for white, grass for high texture, water for low texture.  Add these headings to the data sheet.
5. Take temperature readings in each location several times a day (i.e. 8 a.m., 12 p.m., and 3 p.m.) for several days to ensure that readings have been taken on both sunny days and cloudy days.  When recording, have one student in the team place the meter stick on the ground and hold it in place while another student takes and records the reading.  Encourage students to predict temperatures before actual temperatures are taken.  Record these on the data sheet as well.
6. Have students analyze their data and lead a discussion using the following questions:

• Which colors caused higher temperature readings? (dark colors)
• Which colors caused lower temperature readings? (light colors)
• What does this tell you about how color affects incoming sunlight                               energy? (Darker colors absorb sunlight energy and lighter colors reflect sunlight energy.)
• Which textures caused higher temperature readings? (rough)
• Which textures caused lower temperature readings? (smooth)
• What does this tell you about how texture affects incoming sunlight energy? (Rough surfaces absorb sunlight energy and smooth surfaces reflect sunlight energy.)
• How do the two factors, color and texture, interact to affect incoming sunlight energy?  (A surface that is both dark-colored and rough would absorb more sunlight energy than a surface that is dark-colored and smooth or light-colored and rough.)  How could we test this hypothesis?

7.  Discuss what activities could be done on which surfaces and when the best time would be.  How would surface temperature affect how we dress and what activities we engage in?

8.  Research other factors that affect atmospheric temperature (i.e. earth’s tilt, earth’s distance from the sun, latitude, longitude, cloud cover,  etc.

Heat and Temperature Data