Franklin Fact Archive
Back to Franklin Facts homepage.
Back to TV12
|WEDNESDAY, APRIL 12 - HIGHER UP GETS COLDER?
One of the questions I get all the time goes something like this: Why does it get colder as you go higher in the atmosphere? Shouldn't it get warmer since you're getting closer to the sun? The fact is that as you go up from the ground, it does get colder, but through no fault of the sun.
The key to explaining this is that the gasses that make up the atmosphere - mainly oxygen and nitrogen - aren't particularly good at absorbing sunlight - that it, energy from the sun pretty much passes right through the air to the ground. The ground takes in that energy, and warms up. Then the ground heats the air above it. So the farther you get from the ground, the colder it tends to get.
This basic principle is fundamental to meteorology: In general, the sun heats the ground, and the ground heats the air.