How does altitude affect air temperature?

How does altitude affect air temperature?

• A. Temperature increases as altitude increases
• B. Temperature fluctuates unpredictably with altitude
• C. Temperature decreases as altitude increases
• D. Altitude has no effect on temperature

Answer: (C)

Altitude affects air temperature because the air becomes thinner as you rise, so it holds heat less effectively. In the lowest part of the atmosphere—the troposphere—the temperature generally falls with height, about 6.5°C cooler for every kilometer you climb. That cooling trend is the most consistent pattern we observe in everyday conditions, which is why higher elevations tend to be cooler than the surface. There are occasional layers higher up, like the stratosphere, where temperature can increase with altitude due to processes such as ozone absorbing UV radiation. But for the typical question about how altitude affects air temperature, the key idea is that temperature decreases as altitude increases. The other statements would either contradict this common pattern, describe an unpredictable or no-effect scenario, which doesn’t match the observed behavior in the lower atmosphere.

Altitude affects air temperature because the air becomes thinner as you rise, so it holds heat less effectively. In the lowest part of the atmosphere—the troposphere—the temperature generally falls with height, about 6.5°C cooler for every kilometer you climb. That cooling trend is the most consistent pattern we observe in everyday conditions, which is why higher elevations tend to be cooler than the surface.

There are occasional layers higher up, like the stratosphere, where temperature can increase with altitude due to processes such as ozone absorbing UV radiation. But for the typical question about how altitude affects air temperature, the key idea is that temperature decreases as altitude increases. The other statements would either contradict this common pattern, describe an unpredictable or no-effect scenario, which doesn’t match the observed behavior in the lower atmosphere.