Layers of Earth's Atmosphere

Which layer of the atmosphere contains most of the gases that support life on Earth?

• Stratosphere

• Thermosphere

• Troposphere

• Mesosphere

Why does temperature increase as altitude increases in the stratosphere?

• The ozone layer absorbs ultraviolet radiation from the Sun.

• Air pressure rises with altitude.

• The air becomes denser with height.

• Heat from volcanoes rises into the layer.

What causes the thermosphere to have such high temperatures despite its thin air?

• The Sun’s radiation energizes gas molecules.

• It traps heat from the surface.

• The ozone layer reflects heat upward.

• Energy is absorbed from lightning storms.

Which of the following correctly lists the layers of the atmosphere from lowest to highest?

• Stratosphere, Troposphere, Mesosphere, Thermosphere, Exosphere

• Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere

• Mesosphere, Thermosphere, Troposphere, Stratosphere,

  Exosphere

• Troposphere, Mesosphere, Stratosphere, Thermosphere, Exosphere

Why does air pressure decrease as altitude increases?

• Gravity becomes weaker with height.

• There are fewer gas molecules higher in the atmosphere.

• The ozone layer blocks the movement of air.

• Heat expands the air at high altitudes.

Which layer is responsible for reflecting radio waves, helping long-distance communication?

• Mesosphere

• Ionosphere

• Exosphere

• Troposphere

Why do most meteors burn up in the mesosphere?

• It contains a magnetic field that destroys them.

• It has enough air resistance to cause frictional heating.

• It is the coldest layer, which freezes meteors.

• The ozone layer breaks them apart.

What would most likely happen if the ozone layer were completely destroyed?

• The Earth would cool rapidly.

• Weather patterns would stop.

• More harmful ultraviolet radiation would reach the surface.

• The greenhouse effect would increase dramatically.

Why is weather limited to the troposphere?

• The stratosphere blocks vertical air movement.

• The ozone layer prevents water vapor from rising.

• Clouds cannot form above the tropopause.

• Only the troposphere contains enough water vapor and temperature changes.

Which statement best describes the exosphere?

• It is where auroras occur.

• It has the highest air pressure.

• It gradually transitions into outer space.

• It traps greenhouse gases.