Make lists of parameters of leaf, environmental, or constant parameters
Make lists of parameters of leaf, environmental, or constant parameters
make_leafpar
make_enviropar
make_constants
make_leafpar(replace = NULL) make_enviropar(replace = NULL) make_constants(replace = NULL)
replace |
A named list of parameters to replace defaults. If |
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 |
make_leafpar: An object inheriting from class leaf_parmake_enviropar: An object inheriting from class enviro_parmake_constants: An object inheriting from class constants
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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