Why does the air get colder the higher you go?

We know that hot air gets lighter and rises to the top, so why is it so cold at the top of the mountain?

Picture it like this: the ground is a giant fireplace that keeps us warm, and the further away we go from this fireplace, the colder we feel.

So what heats this fireplace? That is the light and heat radiating from the Sun. Scientists call the sun’s light and heat “radiation”.

Why does the air get colder the higher you go?
The air above can barely hold the heat radiating from the Sun and the heat just passes through there and down to the ground.

Light and heat from the Sun travel through space to the Earth, through the Earth’s atmosphere.

But the atmosphere cannot keep the light and heat of the Sun forever. The heat only passes through the atmosphere. When the sun’s heat reaches the earth’s surface, it is absorbed by the earth. Forests and seas absorb even more heat. Other places, such as snowy lands, tend to reflect the sun’s heat radiation.

The higher you go, the further you are from the “hearth” of the earth, and reaching the top of the mountain is very cold, there are high peaks so cold that people can die in less than an hour if not taken care of. keep warm enough. That’s because the air at such an altitude holds the heat from the Sun very poorly, and only passes through it to reach the Earth’s surface .

In the distant universe there is a lot of radiation from the Sun, and astronauts must wear special clothing to protect from that radiation. But there’s no air in space either, meaning there’s almost nothing to retain the heat radiating from the Sun and so you wouldn’t feel warm if you were to fly up there. So if you accidentally fly into space without special protective clothing, you will freeze to death.