Layers of the Atmosphere

Warm air is ____________ than cold air so it ______________ and forms _____________________.

• less dense; rises; high pressure

• more dense; rises; low pressure

• less dense; rises, low pressure regions

• more dense; sinks; high pressure

• less dense; sinks; low pressure

Answer explanation

Warm air is less dense than cold air, causing it to rise. As it rises, it creates low pressure regions, which is why the correct choice is 'less dense; rises, low pressure regions'.

What is the outermost layer of the atmosphere?

• Troposphere

• Stratosphere

• Mesosphere

• Thermosphere

• Exosphere

Answer explanation

The outermost layer of the atmosphere is the Exosphere. It is where the atmosphere transitions into outer space, lying above the Thermosphere and characterized by extremely thin air.

The troposphere is significant in terms of weather because:

• it contains the ozone layer.

• it is where most weather phenomena occur.

• it is the hottest layer of the atmosphere.

• it is the outermost layer of the atmosphere.

Answer explanation

The troposphere is significant for weather because it is where most weather phenomena occur, including clouds, rain, and storms, making it the layer of the atmosphere directly involved in our daily weather.

Where is the temperature the highest?

• 4

• 2

• 1

• 3

Answer explanation

The temperature is highest at location 4, as indicated by the data provided. This choice reflects the maximum recorded temperature compared to the other options.

What is the coldest layer of the atmosphere?

• Troposphere

• Stratosphere

• Mesosphere

• Thermosphere

Answer explanation

The mesosphere is the coldest layer of the atmosphere, with temperatures decreasing with altitude, reaching as low as -90°C. In contrast, the troposphere and stratosphere are warmer, while the thermosphere is much hotter.

Which gas in our atmosphere is most abundant?

• argon

• oxygen

• nitrogen

• carbon dioxide

Answer explanation

Nitrogen is the most abundant gas in our atmosphere, making up about 78% of the air we breathe. In contrast, oxygen is around 21%, while argon and carbon dioxide are present in much smaller amounts.

Within the troposphere, as altitude increases, temperature _____.

• osculates

• decreases

• increases

• stays constant

Answer explanation

Within the troposphere, temperature decreases with altitude due to the decreasing pressure and density of air, which leads to less heat being retained. Therefore, the correct answer is that temperature decreases.

Photosynthesis (the process in which plants convert carbon dioxide into oxygen) is an example of an interaction between the biosphere and the _____.

• atmosphere

• geosphere

• lithosphere

• hydrosphere

Answer explanation

Photosynthesis involves plants taking in carbon dioxide from the atmosphere and releasing oxygen. This process exemplifies the interaction between the biosphere (living organisms) and the atmosphere (air).

The _____ protects us from the harmful UV rays of the sun.

• troposphere

• ozone layer

• exosphere

• mesosphere

Answer explanation

The ozone layer is a region in the Earth's stratosphere that absorbs most of the sun's harmful ultraviolet (UV) radiation, protecting living organisms from its damaging effects.

Where is the altitude the greatest?

• 1

• 2

• 3

• 4

Answer explanation

The greatest altitude is found in choice 1, which likely represents the highest geographical point compared to the other options. Therefore, option 1 is the correct answer.