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tealeaves (version 1.0.3)

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

Description

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

make_leafpar

make_enviropar

make_constants

Usage

make_leafpar(replace = NULL)

make_enviropar(replace = NULL)

make_constants(replace = NULL)

Arguments

replace

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

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

Details

Leaf parameters:

Symbol R Description Units Default
\(d\) leafsize Leaf characteristic dimension m 0.1
\(\alpha_\mathrm{l}\) abs_l absorbtivity of longwave radiation (4 - 80 \(\mu\)m) none 0.97
\(\alpha_\mathrm{s}\) abs_s absorbtivity of shortwave radiation (0.3 - 4 \(\mu\)m) none 0.50
\(g_\mathrm{sw}\) g_sw stomatal conductance to H2O (\(\mu\)mol H2O) / (m\(^2\) s Pa) 5
\(g_\mathrm{uw}\) g_uw cuticular conductance to H2O (\(\mu\)mol H2O) / (m\(^2\) s Pa) 0.1

Environment parameters:

Symbol R Description Units Default
\(P\) P atmospheric pressure kPa 101.3246
\(r\) r reflectance for shortwave irradiance (albedo) none 0.2
\(\mathrm{RH}\) RH relative humidity none 0.50
\(S_\mathrm{sw}\) S_sw incident short-wave (solar) radiation flux density W / m\(^2\) 1000
\(S_\mathrm{lw}\) S_lw incident long-wave radiation flux density W / m\(^2\) calculated
\(T_\mathrm{air}\) T_air air temperature K 298.15

Constants:

Symbol R Description Units Default
\(c_p\) c_p heat capacity of air J / (g K) 1.01
\(D_{h,0}\) D_h0 diffusion coefficient for heat in air at 0 <U+00B0>C m\(^2\) / s 19.0e-06
\(D_{m,0}\) D_m0 diffusion coefficient for momentum in air at 0 <U+00B0>C m\(^2\) / s 13.3e-06
\(D_{w,0}\) D_w0 diffusion coefficient for water vapour in air at 0 C m\(^2\) / s 21.2e-06
\(\epsilon\) 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
\(R_\mathrm{air}\) R_air specific gas constant for dry air J / (kg K) 287.058
\(\sigma\) s Stefan-Boltzmann constant W / (m\(^2\) K\(^4\)) 5.67e-08

Examples

Run this code
# NOT RUN {
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)
  )
)

# }

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