Chilly heights

[admason]

Why does it get colder the higher you go, even though you're getting closer to the sun?

[Sander]

No matter how high you climb or fly, you're not getting noticeably closer to the sun - it's 93 million miles away so the odd mile doesn't really count. To get any real benefit, you'd have to get about 10,000 miles from the sun.

[incitatus]

The warmth at ground level is due to a buildup of heat in the atmosphere. The higher you get the thinner the atmosphere, and so the less heat it can carry. The radiant heat of the sun can be quite warming, even on a high mountain, but the cold of the surrounding atmosphere negates it.

[nickp]

As a qualified pilot, this is one of the first things we learn. The temperature drops by 1.98 degrees celsius for every 1,000 ft increase in altitude, it is called the 'dry adiabatic lapse rate' and comes from something called 'Boyles Law' - maybe you learned it in physics. It is to do with the pressure of gasses, and pressure changes the higher you climb - that's why you can use a barometer to detect altitude. Boyles Law says that a low pressure gas (including air) is cooler than a higher pressure gas

[Squirrel]

Why does a low pressure gas remove heat from your body (or any warm object) to a greater degree than a high pressure gas? I'm not saying Boyle was wrong, but I can't see why a high p. gas's molecules would actually be warmer than a low p. gas's when both receive the same radiated heat.