make_parameters {tealeaves} | R Documentation |
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 |
Details
Leaf parameters:
Symbol | R | Description | Units | Default |
| leafsize | Leaf characteristic dimension | m | 0.1 |
| abs_l | absorbtivity of longwave radiation (4 - 80 m) | none | 0.97 |
| abs_s | absorbtivity of shortwave radiation (0.3 - 4 m) | none | 0.50 |
| g_sw | stomatal conductance to H2O | ( mol H2O) / (m s Pa) | 5 |
| g_uw | cuticular conductance to H2O | ( mol H2O) / (m s Pa) | 0.1 |
| logit_sr | stomatal ratio (logit transformed) | none | 0 = logit(0.5) |
Environment parameters:
Symbol | R | Description | Units | Default |
| P | atmospheric pressure | kPa | 101.3246 |
| r | reflectance for shortwave irradiance (albedo) | none | 0.2 |
| RH | relative humidity | none | 0.50 |
| S_sw | incident short-wave (solar) radiation flux density | W / m | 1000 |
| S_lw | incident long-wave radiation flux density | W / m | calculated |
| T_air | air temperature | K | 298.15 |
| wind | windspeed | m / s | 2 |
Constants:
Symbol | R | Description | Units | Default |
| c_p | heat capacity of air | J / (g K) | 1.01 |
| D_h0 | diffusion coefficient for heat in air at 0 °C | m / s | 19.0e-06 |
| D_m0 | diffusion coefficient for momentum in air at 0 °C | m / s | 13.3e-06 |
| D_w0 | diffusion coefficient for water vapour in air at 0 C | m / s | 21.2e-06 |
| epsilon | ratio of water to air molar masses | none | 0.622 |
| eT | exponent for temperature dependence of diffusion | none | 1.75 |
| G | gravitational acceleration | m / s | 9.8 |
| Nu | Nusselt number | none | calculated |
| R | ideal gas constant | J / (mol K) | 8.3144598 |
| R_air | specific gas constant for dry air | J / (kg K) | 287.058 |
| s | Stefan-Boltzmann constant | W / (m K ) | 5.67e-08 |
| 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
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)
)
)
[Package tealeaves version 1.0.6 Index]