Scale height

A scale height is a term for a distance over which a quantity decreases by a factor of e (the base of natural logarithms). The scale height is usually shown by a capital letter H.

Scale Height Media

• 

  The earth atmosphere's scale height is about 8.5km, as can be confirmed from this diagram of air pressure p by altitude h: At an altitude of 0, 8.5, and 17 km, the pressure is about 1000, 370, and 140 hPa, respectively.

• 

  A schematic depiction of the force balance in a gas disk around a central object, e.g., a star.