The altitude effect on pressure refers to the phenomenon where atmospheric pressure decreases with increasing altitude. As you ascend in the Earth’s atmosphere, the air becomes less dense, resulting in a decrease in the number of air molecules per unit volume. Consequently, the weight of the column of air above you decreases, leading to a decrease in pressure. This effect is described by the barometric formula, which quantifies the relationship between pressure and altitude in the atmosphere. The formula to calculate the pressure at a given altitude as follows:
Where:
- is the pressure at the given altitude (in Pa),
- is the pressure at sea level (in Pa),
- is the density at the given altitude (in kg/m³),
- is the density at sea level (in kg/m³).