Atmosphere has many secrets to share with mankind. It is a balloon of gases, water vapor, and dust particles with certain weight. As a result, atmosphere exerts certain pressure on the surface. Due to variations in the temperature and other elements in time and space, we equally observe variations in the nature and degree of atmospheric pressures. So, let’s know the difference between low and high pressure.
“Meaning and definition of pressure”
Pressure is an important atmospheric elements having certain characteristics. In short, it is the result of atmospheric weight exerted on the surface of the earth. Being dynamic in nature, pressure has different variations ranging from lower to higher degree in the presence of major determinants — temperature. As per the official meteorological data, the average pressure on the surface is 1013 milibars.
“Cycles of pressure”
As I mentioned earlier that pressure is an interplay among various atmospheric elements including temperature. So, it gets changed according to the degree of temperature in time and space. Let’s have a look at the following sequence of events..
•High temperature = expansion of gases = atmospheric disturbance or depression = convectional current = instability = cloud formation = rainfall = contraction of air = decending air = high pressure or anticyclones = stability……
In this manner, cyclic change in the atmospheric pressure is really never-ending sequence of meteorological events.
As per the properties of gases, they expand and contract with rising and falling of temperature. Whenever temperature rises, gases expand leading to convectional current.
“Convectional current” is nothing but ascending or ascension of air in a cyclic manner due to rise in temperature in the particular place.”Atmospheric disturbance or depression” is the direct product of these events.
Further, idabatic effect paves way for the cloud formation and atmospheric instability. Finally, convectional or cyclonic rainfall begins.
“High pressure or anticyclones”
On the other hand, whenever temperature declines, atmospheric gases contract, leading to formation of “anticyclone”. In this phenomenon, air start decending downward due to cooling effect. In this phenomenon, stability borne out without any form of rain.
In this way, one is associated with convection, instability and cyclonic rainfall. Whereas, other results in stability and dry weather…