Saturation vapour pressure - gritcsenko/Node GitHub Wiki

So, saturation vapour pressure in the pure phase is

$e_w(t)=6.112 \cdot e^{\frac{17.62t}{243.12+t}}$

where t measured in Celsius and pressure in hPa Source

Saturation vapour pressure of moist air is ${e_w}^{'}(p,t)=f(p) \cdot e_w(t)$

where pressure function $pressure function$ is

$f(p)=1.0016+3.15\cdot10^{-6}p-0.074\cdot p^{-1}$

Units of temperature are degrees centigrade and units of pressure are hectopascals (hPa).

1 hPa (hectopascal) = 100 pascals.