Objective: After You Have Completed This Investigation, You Should Be Able To

The Atmosphere

Introduction: The atmosphere is a thin envelope of gases that surrounds the earth. It is held to the earth by the force of gravity, and it moves with the earth as the earth rotates. The atmosphere also has motion of its own, relative to the earth’s surface, called circulation. This general circulation and the many smaller-scale motions within it allow energy to pass from regions of surplus (the tropics) to regions of deficit (the polar regions).

In high school earth science we find it convenient to study the atmosphere by dividing the entire atmosphere into zones based on temperature. There are other ways to classify the atmosphere, but this method is most convenient for us since you haven’t taken chemistry or physics yet.

Objective: After you have completed this investigation, you should be able to

1)Interpret the Selected Properties of Earth’s Atmosphere graphs on page 15 of the Earth Science Reference Tables.

Materials:

Ruler

Pencil

Colored Pencils

Procedure:

1)CAUTION: In this lab, it is important for each student to read directions carefully and follow those directions exactly. Each individual student will be required to demonstrate his/her ability to follow directions as part of the final exam in June. Each lab this year gives you experience in reading and following directions.
In this lab, when you plot locations, make sure you carefully estimate positions. Use a ruler whenever possible.

2)The troposphere is part of the atmosphere that contains all of the weather that we are familiar with on earth. The boundary of the troposphere is at an altitude of 11 km above the surface and is called the tropopause. On your graph, draw a line in regular pencil at 11 km to represent the tropopause. Use a ruler to draw the line. Make sure the line is straight and is parallel to the bottom of the graph.

3)In the left margin (outside of the graph), label this line 11 km. In the right margin (outside of the graph), label this line tropopause. Below the word tropopause, write the word troposphere.

4)Now reread the directions to step 3. Did you put labels where directed? If not, make corrections before you proceed.

5)The average temperature at the surface of the earth is 150C. Put a red dot on the graph to represent this fact.

6)The average temperature at the tropopause is –550C. Put a red dot on the graph to represent this fact.

7)Using red pencil, connect the dot in step 5 with the dot in step 6. Answer question #1 on the Report Sheet.

8)The Statosphere extends from the tropopause to an altitude of 50 km. The boundary of the stratosphere at 50km is called the stratosphere. Draw a regular pencil line on your graph at 50 km to represent the stratopause. Use a ruler to draw the line. Make sure the line is straight and is parallel to the bottom of the graph.

9)In the left margin (outside of the graph), label this line 50 km. In the right margin (outside of the graph), label this line stratopause. In the space between the words tropopause and stratopause, write the word stratosphere.

10)Now reread the directions to step 9. Did you put labels where directed? If not, make corrections before you proceed.

11)The average temperature at the stratopause is 00C. Put a red dot on the graph to represent this fact.

12)Using a red pencil, connect the dot in step 11 with the dot from step 6. Answer question #2 on the Report Sheet.

13)The ozone layer extends from an altitude of 10km to 50 km but is most concentrated at an altitude of 25 km. Use the yellow pencil to shade in the location of the ozone layer. Use the purple pencil to draw a wavy line to indicate where ozone is most concentrated. Answer question #3 on the Report Sheet.

14)Now reread the direction to step 13. Do you have a wide yellow band of color all the way from left to right? The bottom of the yellow band should be 10 km above the bottom of the graph and the top of the yellow band should be 50 km above the bottom of the graph. Did you make a wavy purple line from left to right and 25 km above the bottom of the graph? If not, make correction before you proceed?

15)The mesosphere extends from the stratopause to an altitude of 50 miles. (Yes, miles. This is not a typing error. Remember, in this lab you are demonstrating your ability to follow directions.) The boundary of the mesosphere at 50 miles is called the mesopause. Draw a regular pencil line on your graph at 50 miles to represent the mesopause.

16)In the left margin (outside of the graph), label this line 50 miles. In the right margin (outside of the graph), label this line mesopause. In the space between the words stratopause and mesopause, write the word mesosphere.

17)The average temperature at the mesopause is -900C. Put a red dot on the graph to represent this fact.

18)Using red pencil, connect the dot in step 17 with the dot in step 11. Answer questions #4 and #5 on the Report Sheet.

19)The thermosphere extends from the mesopause to an altitude of approximately 120 km. (No, your teacher didn’t forget something. In this lab, you are demonstrating your ability to follow directions.)

20)The average temperature at 120 km is +1000C. Put a red dot on the graph to represent this fact.

21)Using a red pencil, connect the dot in step 20 with the dot in step 17. Answer questions #6 on the Report Sheet.

22)In the margin between the 1000C red dot and the word mesopause, write the word thermosphere.

23)Mt. Everest is about 8.8 km high. Anywhere along the surface and using the green pencil draw in a mountain to this elevation to represent Mt. Everest. In other words, make a green triangle with its base on the bottom line of the graph. The peak at the top of the green triangles should be at the 8.8 km level.

24)Answer question #7 on the Report Sheet.

25)Unmanned weather balloons called radiosondes travel to an altitude of about 40 km. Use a blue pencil to draw in a blue dot to represent the weather balloon at this altitude.

26)Answer question #8 on the Report Sheet.

27)The Concorde Supersonic Transport planes can fly at an altitude of 16 km. Use the black colored pencil to draw in a small plane at this altitude.

28)Answer question #9 on the Report Sheet.

29)Now turn to page 14 (top) on your Reference Table. Compare your graph to the graph in your reference Table

30)Use your Reference Table, page 14 (top) to answer questions 10 to 16.

31)Turn in your completed lab.