Air Pressure

Pages 10-14

Weather Textbook


Air has mass therefore it also has:


Air Pressure: The weight of a column of air pressing down on an area of Earth.


Barometer: An instrument that measures air pressure.


Altitude and its effect on air pressure and density:

·        Air pressure decreases as altitude increases

         The higher up you go the less air is pushing down on you.


·        As air pressure decreases, density decreases. 

         The higher up you go the less dense the air is.


   The molecules of air are further apart.  This means that the amount of oxygen in a given space is less, so you would have trouble breathing.