pressure.from.elevation {bigleaf} | R Documentation |
An estimate of mean pressure at a given elevation as predicted by the hypsometric equation.
pressure.from.elevation(
elev,
Tair,
VPD = NULL,
constants = bigleaf.constants()
)
elev |
Elevation a.s.l. (m) |
Tair |
Air temperature (deg C) |
VPD |
Vapor pressure deficit (kPa); optional |
constants |
Kelvin- conversion degC to Kelvin |
Atmospheric pressure is approximated by the hypsometric equation:
pressure = pressure_0 / (exp(g * elevation / (Rd Temp)))
pressure - |
Atmospheric pressure (kPa) |
The hypsometric equation gives an estimate of the standard pressure at a given altitude. If VPD is provided, humidity correction is applied and the virtual temperature instead of air temperature is used. VPD is internally converted to specific humidity.
Stull B., 1988: An Introduction to Boundary Layer Meteorology. Kluwer Academic Publishers, Dordrecht, Netherlands.
# mean pressure at 500m altitude at 25 deg C and VPD of 1 kPa
pressure.from.elevation(500,Tair=25,VPD=1)