Exercises: The atmosphere

Air is made up of approximately 78% nitrogen, 21% oxygen, and 1% other gases (argon, carbon dioxide, water vapor, etc.). Order these components from highest to lowest proportion and represent the data using a simple bar graph.

You can do it on paper and send a photo with your answer.

The diagram shows the layers of the atmosphere (not drawn to scale).

1. a) Which layer is labeled with "?"?
2. b) In which layer do clouds form and storms occur?
3. c) Which gas forms an area in the layer labeled with "?" that absorbs ultraviolet radiation from the Sun?

State two functions of the atmosphere that make life on Earth possible, and briefly explain one of them.

Name the two most abundant gases in air and state their approximate proportion.

State whether these statements about the atmosphere are true or false and correct the false ones: air is made up only of oxygen; the troposphere is the layer where weather occurs; the exosphere is the layer closest to the surface.

Explain in your own words what atmospheric pressure is and reason why it is lower at the top of a mountain than at sea level.

A commercial airplane flies at about 11 km altitude and the International Space Station orbits at about 400 km. State in which layer of the atmosphere each one moves.

Name two differences between the troposphere and the outermost layers of the atmosphere, regarding air density and the phenomena that occur in them.

As you climb a mountain, the temperature drops, even though you are closer to the Sun. Explain which layer of the atmosphere this temperature drop corresponds to and explain why the peak of a high mountain is cold.

What is the ozone layer, which layer of the atmosphere is it located in, and why is its depletion a concern?

The Moon has virtually no atmosphere. State two consequences of this fact related to the functions that the atmosphere performs on Earth.

In the troposphere, temperature decreases with altitude, but in the stratosphere it increases. Relate this change of trend to the absorption of ultraviolet radiation by the ozone layer.

In high mountains, each breath provides less oxygen than at sea level. Explain how this fact is related to atmospheric pressure and why mountaineers need to acclimatize for days before climbing a very high summit.

The atmosphere is compared to a blanket wrapped around the Earth. Explain the resemblance: how it filters part of the solar radiation during the day and how it retains part of the heat during the night.

CFC gases, formerly used in aerosols and refrigerators, destroyed ozone and were banned by the Montreal Protocol. Explain the risk their use posed and why that agreement is considered a success of international cooperation.

Water vapor is a variable component of air. Explain what happens when a mass of humid air rises and cools down, and relate it to the formation of clouds.

A rocky exoplanet similar to Earth has been discovered that receives comparable stellar radiation, but whose atmospheric analysis indicates that it lacks an ozone layer in its middle region and does not retain water vapor in its lower layers. Reasonably justify which protective and regulating functions fulfilled by Earth's troposphere and stratosphere would be absent on that planet, and predict two critical consequences for the viability of life on its surface.

A classmate claims that it is absurd to attribute global warming to carbon dioxide ($\text{CO}_2$), since making up only 0.04 % of the air, nitrogen (78 %) and oxygen (21 %) must be the real culprits responsible for trapping heat. Refute their position by explaining the differential behavior of these gases toward solar radiation and terrestrial infrared radiation, and predict what would happen to the planet's average temperature if $\text{CO}_2$ and the other greenhouse gases were to disappear entirely.

A weather balloon records the following temperatures as it rises: 15 °C at the surface, −50 °C at an altitude of 10 km, 0 °C at 45 km, and −80 °C at 70 km. State which layers of the atmosphere it passes through in each section and explain the change in trend observed in the data.

Mars has an atmosphere about a hundred times thinner than Earth's and made almost entirely of $\text{CO}_2$. Explain why temperature differences between day and night on Mars are much greater than on Earth, even though $\text{CO}_2$ is a greenhouse gas.