Earth-Based Temperature Activities

Teachers' Background Materials

Investigating the question "How Does Near-Surface Air Temperature Change with Height on Earth?"

Below are background information for two activities that explore "temperature profiles" -- temperatures taken at various heights and recorded over time. By examining the raw data and associated graphs students will look for patterns that reveal day-length, heating of the air over a day, and the temperature change of air with height.

Activities:

• Download and Analysis of Earth-Based Temperature Data has students analyze a data set of Earth temperatures taken during the Mars Pathfinder mission.
• Collection and Analysis of Earth-Based Temperature Data shows students how to collect their own profile data using simple supplies.

Questions to consider (Suggestions/answers in parentheses)

1. What about the graph helps you distinguish between night and day? (The height of the temperature curve differentiates night from day. Higher temperatures for day, lower for night.)
2. Does the temperature change at the same rate each morning? (No, the heating rates are slightly different each day--judged from the steepness of the temperature curve.).
3. Is the rate of increase the same as the rate of decrease over a day? (No, the temperature curve is not "symmetric"--the air warms faster than it cools.)
4. Describe the temperature profile for the warmest part of a day. (The air closest to the ground is warmer than the air at 1.00 meters.)
5. Describe the temperature profile for the coldest part of a day. (The air at 1.00 meters is warmer than the air closest to the ground.)
6. Are the temperature profiles for warmest and coldest parts of a day the same? (No, they are reversed.)
7. Is the temperature profile for the warmest part of a day the same for all days? (Yes, if temperatures are taken in a place where the sun is shining on the ground.)
8. Answer only if you have completed Download and Analysis of Mars-Based Temperature Data --Is the change you described in the previous question the same for temperatures on Mars? (Yes, the basic profiles are the same, although the temperatures and extremes are different.)
9. What factors might affect your temperature readings? (Accuracy of thermometers, proficiency in reading thermometers, whether thermometers are shielded from direct sunlight, the season in which measurements are taken, location of thermometers (in sun or shade), surface over which temperatures are taken (concrete, grass, soil, etc.), actual differences in air temperature over height.)
10. If you were to do this experiment again, what would you do differently? (Answers will vary--look for ways to improve accuracy and extend conceptual understanding.)

Suggestions for "original" experiments:

• What is the effect of the wind on air temperature?
• What is the air temperature at 10 meters? 100 meters? 1,000 meters? 10,000 meters?
• Which conditions combine to make the greatest difference in a temperature profile? The least difference?
• What is the relationship to soil temperature and the air temperature at 0.25 meters? At 1.00 meters?
• What is the relationship between change in air pressure to the change in temperature during the day? Is it the same at night?
• How does the temperature profile over water compare to the profile over land?

© 1998 Live from Earth and Mars, Rich Edgerton, and Janice DeCosmo