What does the earth do with the heat it receives from the sun?
The earth gives off its heat to the air nearest to it.
What becomes of this heated air?
This heated air ascends, and colder air comes to take its place; thus producing winds.
Are all parts of the earth heated alike by the sun?
No; they are not all heated alike.
How does this unequal heating affect the air?
It causes currents in the air all over the world.
Does water give off heat as rapidly as the earth does?
No; water is a poorer radiator of heat than the earth is.