stdatm.m

Syntax:

pressure = stdatm(elevation)

This function converts elevation $z$in meters to atmospheric pressure $p$ in hPa using the pressure-elevation relationship in the ICAO Standard Atmosphere:

$$p(z) = p_{s} exp{ \Big\{ - \frac{gM}{R\xi} \left[ \ln T_{s} - \ln \left( T_{s} - \xi z \right) \right] \Big\}}$$ (75)

where sea level pressure $P_{s} = 1013.25$ hPa; sea level temperature $T_{s} = 288.15$ K; and the adiabatic lapse rate $\xi = 0.0065$ K $\cdot$ m$^{-1}$. $M$ is the molar weight of air, $g$ the acceleration due to gravity, and $R$ the gas constant, giving $gM/R =$ 0.03417 K $\cdot$ m$^{-1}$.

For further discussion see:

Stone, J., 2000. Air pressure and cosmogenic isotope production. Journal of Geophysical Research 106, pp. 23,753-23,759.