make_parameters: Make lists of parameters of leaf, environmental, or constant...

Description Usage Arguments Details Value Examples

Description

Make lists of parameters of leaf, environmental, or constant parameters

make_leafpar

make_enviropar

make_constants

Usage

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Arguments

replace

A named list of parameters to replace defaults. If NULL, defaults will be used.

Details

Leaf parameters:

Symbol R Description Units Default
d leafsize Leaf characteristic dimension m 0.1
α_l abs_l absorbtivity of longwave radiation (4 - 80 μm) none 0.97
α_s abs_s absorbtivity of shortwave radiation (0.3 - 4 μm) none 0.50
g_sw g_sw stomatal conductance to H2O (μmol H2O) / (m^2 s Pa) 5
g_uw g_uw cuticular conductance to H2O (μmol H2O) / (m^2 s Pa) 0.1
logit(sr) logit_sr stomatal ratio (logit transformed) none 0 = logit(0.5)

Environment parameters:

Symbol R Description Units Default
P P atmospheric pressure kPa 101.3246
r r reflectance for shortwave irradiance (albedo) none 0.2
RH RH relative humidity none 0.50
S_sw S_sw incident short-wave (solar) radiation flux density W / m^2 1000
S_lw S_lw incident long-wave radiation flux density W / m^2 calculated
T_air T_air air temperature K 298.15
u wind windspeed m / s 2

Constants:

Symbol R Description Units Default
c_p c_p heat capacity of air J / (g K) 1.01
D_h0 D_h0 diffusion coefficient for heat in air at 0 °C m^2 / s 19.0e-06
D_m0 D_m0 diffusion coefficient for momentum in air at 0 °C m^2 / s 13.3e-06
D_w0 D_w0 diffusion coefficient for water vapour in air at 0 C m^2 / s 21.2e-06
ε epsilon ratio of water to air molar masses none 0.622
eT eT exponent for temperature dependence of diffusion none 1.75
G G gravitational acceleration m / s^2 9.8
Nu Nu Nusselt number none calculated
R R ideal gas constant J / (mol K) 8.3144598
R_air R_air specific gas constant for dry air J / (kg K) 287.058
σ s Stefan-Boltzmann constant W / (m^2 K^4) 5.67e-08
Sh Sh Sherwood number none calculated

Value

make_leafpar: An object inheriting from class leaf_par
make_enviropar: An object inheriting from class enviro_par
make_constants: An object inheriting from class constants

Examples

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library(tealeaves)

# Use defaults
cs <- make_constants()
ep <- make_enviropar()
lp <- make_leafpar()

# Replace defaults

ep <- make_enviropar(
  replace = list(
    T_air = set_units(300, K)
  )
)

lp <- make_leafpar(
  replace = list(
    leafsize = set_units(c(0.1, 0.2), m)
  )
)

cdmuir/tealeaves documentation built on June 21, 2020, 2:32 a.m.