Barometric Formula

The barometric formula is a formula used to model how atmospheric pressure, or air density, changes with altitude. Where temperature varies linearly with height within an atmospheric layer, the formula takes a power law form built from the layers reference pressure, reference temperature, temperature gradient, and the gas constant; where temperature is treated as constant within a layer, it instead takes an exponential form relating pressure to the height above a reference level, gravitational acceleration, and the mean molar mass of air. Air density can then be found from the resulting pressure and temperature through the ideal gas relationship. The formula is considered a reasonably good model of the atmosphere from sea level up to about 86 kilometers, and its exponential form matches observations most closely above about 51 kilometers. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/