Earth’s atmosphere consists of 78% nitrogen, 21% oxygen and 1% argon.   The weight of one cubic foot of air molecules increases as barometric pressure increases and decreases as temperature increases.   The more one cubic foot of air molecules weigh, the more air molecules are present.

     At sea level, all of earth’s atmospheric total height pushes downward.   All of earth’s atmospheric total height pushing down increases barometric pressures.   High barometric pressures mean high air molecule densities.   High air molecule densities mean high air molecule weight per cubic foot.   Consequently, sea level cities have high barometric pressures.

     At high altitudes, less than all of earth’s atmospheric total height pushes downward.   Less than all of earth’s atmospheric total height pushing down decreases barometric pressure.   Low barometric pressures mean low air molecule densities.   Low air molecule densities mean low air molecule weight per cubic foot.   Consequently, high altitude cities have lower barometric pressures.

     High temperatures mean low air molecule densities.   Low air molecule densities mean low air molecule weight per cubic foot.   Consequently, high temperature cities have low air molecule densities.   Low temperatures mean high air molecule densities.   High air molecule densities mean high air molecule weight per cubic foot.   Consequently, low temperature cities have high air molecule densities.

     High air molecule densities significantly decelerate fastballs.   High air molecule densities significantly increase the direction changes of breaking pitches, such as curves.   Because high barometric pressures increase air molecule densities, breaking ball pitchers should pitch in high barometric pressure areas.   Because low temperatures increase air molecule densities, breaking ball pitchers should pitch in cold weather.   Therefore, breaking ball pitchers thrive at cold, sea level cities.

     Low air molecule densities do no significantly decelerate fastballs.   Low air molecule densities do not significantly increase the direction changes of breaking pitches, such as curves.   Because low barometric pressures decrease air molecule densities, fastball pitchers should pitch in low barometric pressure area.   Because high temperatures decrease air molecule densities, fastball pitchers should pitch in hot weather.   Therefore, fastball pitchers thrive at hot, high altitude cities.