Imagine that you are driving up a mountain on a very curvy road at night when the air is very still and not moving. The air temperature is getting colder and colder as you drive up the mountain. Which of the following best describes what happened to the air temperature?

Diathermy and atmospheric pressure

Explanation:

When the energy from the Sun comes to the Earth, it hits first the atmosphere, but the air contained is almost unaffected by it because the molecules are not tight enough to absorb its incoming energy.

Later on, the sunlight reaches the soil, thus absorbing part of the energy and reflecting the rest. Because of this reflection, the air near to the ground begins to heat through convection and as it gains height the air pressure (thus the air molecules begin to separate more from each other) decreases and the energy transfer to them is more difficult. As a result, as you gain height, the air temperature decreases at a rate of 6.8 ºC every 1,000 meters.