Compute \(\rho\), the in-situ density of dry air.

airRho(temperature, pressure, humidity)

Arguments

temperature

in-situ temperature, in \(^\circ\)C.

pressure

numeric value for pressure in Pa (not the kPa used in public weather forecasts).

humidity

ignored at present

Value

In-situ dry-air density, in kg/m\(^3\).

Details

This will eventually be a proper equation of state, but for now it just uses a dry-air formula posted on wikipedia (i.e. not trustworthy).

References

  1. https://en.wikipedia.org/wiki/Density_of_air

  2. National Oceanographic and Atmospheric Agency, 1976. U.S. Standard Atmosphere, 1976. NOAA-S/T 76-1562. (A PDF of this document may be available at http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19770009539_1977009539.pdf or http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA035728 although neither link has proven to be reliable.)

Author

Dan Kelley

Examples

degC <- seq(0, 30, length.out = 100)
p <- seq(98, 102, length.out = 100) * 1e3
contour(x = degC, y = p, z = outer(degC, p, airRho), labcex = 1)