bigleaf (version 0.7.0)

stability.parameter: Stability Parameter "zeta"

Description

calculates "zeta", a parameter characterizing stratification in the lower atmosphere.

Usage

stability.parameter(data, Tair = "Tair", pressure = "pressure",
  ustar = "ustar", H = "H", zr, d, constants = bigleaf.constants())

Arguments

data

Data.frame or matrix containing all required variables

Tair

Air temperature (degC)

pressure

Atmospheric pressure (kPa)

ustar

Friction velocity (m s-1)

H

Sensible heat flux (W m-2)

zr

Instrument (reference) height (m)

d

Zero-plane displacement height (m)

constants

Kelvin - conversion degree Celsius to Kelvin cp - specific heat of air for constant pressure (J K-1 kg-1) k - von Karman constant (-) g - gravitational acceleration (m s-2)

Value

\(\zeta\) -

stability parameter (-)

Details

The stability parameter \(\zeta\) is given by:

$$\zeta = (zr - d) / L$$

where L is the Monin-Obukhov length (m), calculated from the function Monin.Obukhov.length. The displacement height d can be estimated from the function roughness.parameters.

Examples

# NOT RUN {
df <- data.frame(Tair=25,pressure=100,ustar=seq(0.2,1,0.1),H=seq(40,200,20))
stability.parameter(df,zr=40,d=15)

# }