Question

At different places one earth, depending on elevation, air pressure varies. What causes air pressure?

Answer 1

Weight of air

Depending on elevation, the air pressure varies. This is because of the weight of the air that is exerting pressure on earth. At higher elevation, there is less layer of air that is exerting pressure so the atmospheric pressure is also less. At lower altitudes or at sea level, more layer of air is exerting pressure so the atmospheric pressure is also more. The sun’s energy has nothing to do with air pressure. The energy that the Earth gets from the sun is more or less constant. The same with density of nitrogen, and the earth’s magnetic field, they have nothing to do with air pressure.