Buoyancy

     This section explores the contribution that buoyancy plays in the role of thunderstorm development.   The concept of buoyancy is credited to the Greek mathematician Archimedes (287-212 BC).   Archimedes found that the weight a liquid displaced by a floating object is equal to the weight of the body.  This buoyant force results in objects which will sink if they are heavier than the surrounding fluid and will rise if they are lighter.  If the object weighs the same as an equivalent volume of the fluid, it will be in equilibrium and remain motionless.   In our case the object we will be discussing is an air parcel (bubble of air) submersed in the atmosphere.  To understand the motion of a parcel with respect to the atmosphere we need to evaluate the density differences between the surrounding air and the parcel.   Density difference are related to the temperature in the atmosphere.  The colder (warmer) an object is the more dense (less) it will be.  Therefore  the temperature differences between the atmosphere and the parcel is the determining factor in whether the parcel will rise, fall, or stay at the same location in the atmosphere.  These three possibilities either increase the chance of thunderstorms, decrease the the chance, or have little effect on the chance, respectively.