dot-get_dwv: d_wv: water vapour gradient (mol / m ^ 3)

.get_dwvR Documentation

d_wv: water vapour gradient (mol / m ^ 3)


d_wv: water vapour gradient (mol / m ^ 3)


.get_dwv(T_leaf, pars, unitless)



Leaf temperature in Kelvin


Concatenated parameters (leaf_par, enviro_par, and constants)


Logical. Should function use parameters with units? The function is faster when FALSE, but input must be in correct units or else results will be incorrect without any warning.


Water vapour gradient: The water vapour pressure differential from inside to outside of the leaf is the saturation water vapor pressure inside the leaf (p_leaf) minus the water vapor pressure of the air (p_air):

d_\mathrm{wv} = p_\mathrm{leaf} / (R T_\mathrm{leaf}) - RH p_\mathrm{air} / (R T_\mathrm{air})

Note that water vapor pressure is converted from kPa to mol / m^3 using ideal gas law.

Symbol R Description Units Default
p_\mathrm{air} p_air saturation water vapour pressure of air kPa calculated
p_\mathrm{leaf} p_leaf saturation water vapour pressure inside the leaf kPa calculated
R R ideal gas constant J / (mol K) 8.3144598
\mathrm{RH} RH relative humidity % 0.50
T_\mathrm{air} T_air air temperature K 298.15
T_\mathrm{leaf} T_leaf leaf temperature K input


Value in mol / m^3 of class units


# Water vapour gradient: 

leaf_par <- make_leafpar()
enviro_par <- make_enviropar()
constants <- make_constants()
pars <- c(leaf_par, enviro_par, constants)
T_leaf <- set_units(300, K)
T_air <- set_units(298.15, K)
p_leaf <- set_units(35.31683, kPa)
p_air <- set_units(31.65367, kPa)

d_wv <- p_leaf / (pars$R * T_leaf) - pars$RH * p_air / (pars$R * T_air)

cdmuir/tealeaves documentation built on Feb. 28, 2024, 8:21 a.m.