Barometric pressure, or atmospheric pressure, is the pressure exerted by the tiny molecules of air present in the atmosphere. These molecules have very little weight, and in spite of being extremely tiny, they can be compressed and fitted into a smaller space, which gives rise to high barometric pressure. Since a barometer is the instrument that is used to measure this pressure, it is known as barometric pressure. Barometric pressure is measured in units of millibar.
Barometric pressure is constantly being applied on people. But since there is air inside people's bodies, this pressure is counteracted, and this allows people to breathe freely. But there are certain ill effects that can affect people due to high barometric pressure.
Pain in the Ear
The number of molecules that people are surrounded by has an effect which varies from one place to another. For example, the air pressure in hilly regions is considerably less than the air pressure in the plains. Therefore, people experience a condition called “ear popping” which helps to balance the pressure inside and outside the body. This may result in pain in one or both the ears for some people.
Pain in the Joints
The rate of air compression determines the degree to which a person suffers from high altitude. Surprisingly, high barometric pressure is found to have a direct impact on those who suffer from osteoarthritis. The "American Journal of Medicine" studied 200 patients from different geographical locations and confirmed that the barometric pressure has a direct influence on the severity of joint pain. This is because the intra-particular pressure (i.e., the pressure inside the joints) is lower than the barometric pressure, and this results in more pain in the joints.
A more common effect due to barometric pressure is getting a headache, which people often mistake as a sinus headache. Neurologists found that the changes in the barometric pressure cause small pressure changes in the fluid that is present in the brain. This triggers migraine (i.e., a condition marked by recurrent and severe headaches) receptors in the brain, resulting in a headache. Other ill effects--including asphyxiation, paralysis and a dull throbbing in the joints--can affect divers and compressed air workers.