Earth's Atmosphere

What is the most common gas in the atmosphere?

• nitrogen
• oxygen
• water vapor
• carbon dioxide

What is the atmospheric layer closest to the surface?

• troposphere

• stratosphere

• mesosphere

• thermosphere

Directly above the troposphere is the _________.

• stratosphere
• mesosphere
• exosphere
• thermosphere

Within the stratosphere is the ozone layer. What does the ozone layer do?

• It protects us from meteors

• It protects us from violent solar flares

• It protects us from ultra violet radiation

• It helps us breathe

Directly above the stratosphere is the _________.

• mesosphere
• troposphere
• thermosphere
• exosphere

In which two layers does temperature decrease with altitude?

• mesosphere and troposphere

• troposphere and stratosphere

• stratosphere and thermosphere

• thermosphere and exosphere

In which layer do virtually all weather phenomena take place?

• troposphere

• mesosphere

• stratosphere

• thermosphere

Percentage of Earth's atmosphere that carbon dioxide makes up

• less than 1%
• 5%
• 20%
• 80%

Layer of Earth's atmosphere where most of the water vapor and carbon dioxide is found

• thermosphere
• mesosphere
• stratosphere
• troposphere

Uppermost layer of Earth's atmosphere

• thermosphere
• mesosphere
• stratosphere
• troposphere