Where in the Air: Atmosphere Layers — Practice Worksheet

Vocabulary

• Atmosphere – The layers of air that surround the Earth.
• Troposphere – The lowest layer of the atmosphere, closest to Earth's surface, where weather and clouds happen.
• Stratosphere – The layer above the troposphere that contains the ozone layer and has very stable, calm air.
• Mesosphere – The layer of the atmosphere where meteors (shooting stars) usually burn up; it has the coldest temperatures of any layer.
• Thermosphere – The layer with very little air, where temperatures get extremely hot even though it would feel cold to a person.
• Ozone Layer – A part of the stratosphere that absorbs some of the Sun's dangerous ultraviolet rays.
• Altitude – The height of something above Earth's surface.
• Armstrong Line – The altitude at which liquids boil at human body temperature, so a full pressure suit is needed.

Comprehension

1. List the layers of the atmosphere in order, starting with the layer closest to Earth's surface.
2. Which layer of the atmosphere is described as the densest and contains most of the atmosphere's mass?
3. What happens to air temperature as altitude increases in the troposphere? What happens in the stratosphere?
4. Why is the mesosphere important for meteors ("shooting stars")?
5. Explain why the thermosphere can have extremely high temperatures but still feel cold to a person.
6. In which layer would you find commercial jetliners, hot air balloons, and weather? What do these objects have in common?
7. Why do pilots flying at the altitude of the Armstrong Line need a full pressure suit?
8. What is the function of the ozone layer, and in which layer of the atmosphere is it located?

Think & Write

1. If you could travel through all the layers of the atmosphere, describe what you might see or feel as you go from the troposphere up to the thermosphere.
2. Choose one object from the text (such as a weather balloon, meteor, or satellite) and explain why it is found in the layer that it is. Use details from the text to support your answer.
3. Why do you think the troposphere is described as "the most complex" layer of the atmosphere? Use evidence from the text.

Answer Key

1. Troposphere, Stratosphere, Mesosphere, Thermosphere (and beyond).
2. The troposphere — about 75% of the atmosphere's mass is found there.
3. In the troposphere, temperature declines as altitude increases. In the stratosphere, temperature rises as altitude increases because of radiation absorbed by the ozone layer.
4. Meteors often burn up while passing through the mesosphere as they enter Earth's atmosphere.
5. Even though air molecules in the thermosphere absorb huge amounts of energy from the Sun and reach very high temperatures, there are so few air molecules that there isn't enough to transfer heat to a person, so it would feel cold.
6. The troposphere — these objects/conditions are all located close to Earth's surface, where weather, clouds, and most flying vehicles exist.
7. Because the Armstrong Line is the altitude at which liquids boil at human body temperature, so a pressure suit is needed to protect the body.
8. The ozone layer absorbs some of the Sun's dangerous ultraviolet rays, preventing them from reaching Earth's surface; it is located in the stratosphere.