If you were to dive beneath the ocean's surface, you would encounter increasing pressures and decreasing temperatures with increasing depth. Creatures deep in the ocean experience a much different environment than those living near the surface.
Likewise, the atmospheric environment at sea level is quite different than that at higher altitudes. From early exploration in hot-air and lighter-than-air balloons to current research about the atmospheric and beyond, scientists have gained a good understanding of conditions in all parts of the atmosphere.
Picture yourself in a craft designed to fly upward from the earth's surface to the farthest regions of our atmosphere. The instruments in your imaginary craft have been set to record altitude, air temperature and air pressure. One-liter gas samples can be taken at any time. Automated instruments will give you a report on each sample's mass, number of molecules, and composition.
During you ascent, the composition of the air remains essentially constant at 78% N2, 21% 02, 1% Ar, plus trace elements. At 12 km you notice you are above the clouds. Even the tallest mountains are far below. The sky is light blue; the sun shines brilliantly. The craft in now above the region where most commercial aircraft fly and above where weather develops. Above 12 km, air composition is about the same as at lower altitudes, except your instruments detect more ozone (03). You also notice that the air is quite calm, unlike the turbulence you encountered at 12 km.
Air samples taken at 50-85 km contain relatively few particles. Those present are ions such as 02+ and N0+. Above 200 km, your radar detects various communication satellites in orbit. Your aircraft now returns to the earth's surface. It's time to analyze the data you collected.
Plotting the Data
Table 1 summarizes the data recorded during the flight. The last two columns provide composition of equal-volume(1-L) samples of air at different altitudes.
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Construct table 1 on the stat editor of the calculator by assigning:
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Questions
1. Compare the ways air temperature and pressure change with increasing altitude.
2. Would you expect the air pressure to rise or fall if you traveled from sea level to
3. Here's an observation you can make for yourself: When two rubber toilet plungers are pressed together, it becomes quite difficult to separate them.
4. a. Suppose you take one-liter samples of air at several altitudes. How do the following change?
5. Does the graph of mass vs. molecules illustrate a predictable relationship? Explain.
6.Scientists often divide the atmosphere into four layers: troposphere(near earth), stratosphere, mesosphere and thermosphere(outermost layer).
