Why is the atmospheric pressure measured at sea level? Why is the atmospheric pressure not felt by us?

Explanation

Since the composition and the density of air varies with the altitude, the pressure exerted by air also varies. The atmospheric pressure decreases with an increase in the altitude. It is due to this reason that the atmospheric pressure is measured at sea level where it is maximum. At sea level, atmospheric pressure is almost equal to the weight of a 1 kg mass acting on every square centimetre. We do not feel the atmospheric pressure because the pressure inside the body is equal to the atmospheric pressure.