Mean Sea Level Pressure Highs and Lows Ridges and Troughs Fronts Thickness Temperature Advection Definitions

Mean Sea level Pressure Distribution of Air Molecules in the Atmosphere Air pressure is defined as the weight of the air in a column stretching from the surface to the top of the atmosphere. Most of this weight is confined to the troposphere. As a result of gravity, the distribution of air molecules is greatest near the ground and decreases with height. This distribution is directly related to air density, which also decreases with increasing altitude.