paraminit: Initialise paramaters for first time step of model

In ilyamaclean/microclimc: Below or above canopy microclimate modelling with R

Initialise paramaters for first time step of model

Description

Generates a set of climate and conductivity parameters for running the first time step of the model

Usage

paraminit(m, sm, hgt, tair, u, relhum, tsoil, Rsw)

Arguments

m	number of canopy layer nodes
sm	number of soil layers
hgt	height of canopy (m)
tair	air temperature at reference height (deg C)
u	wind speed at reference height (m/s)
relhum	relative humidity at reference height (percentage)
tsoil	stable temperature below deepest soil layer. Usually ~mean annual temperature (deg C). See details.
Rsw	total incoming shortwave radiation (W / m^2)

Details

All values are approximate. Values for tc and tsoil are derived by linear intepolation between tair and tsoil. Values for Rabs are derived from Rsw but attenuate through the canopy. Values for tleaf are derived from tc and Rabs. Values for rh are the same as relhum. Values for gt gv and gha are typical for decidious woodland with wind above canopy at 2 m/s. gt is scaled by canopy height and m (and hence distance between nodes). The first value represents conductivity between the ground and the lowest canopy node. The last value represents conductivity between the air at 2 m above canopy and the highest canopy node.

Value

a list with the following elements:

tc a vector of air temperatures for each canopy layer (deg C)

soiltc a vector of airsoil temperatures for each soil layer (deg C)

tleaf a vector of leaf temperatures for each canopy layer (deg C)

tabove initially set above canopy temperature, here set as tair

uz a vector of wind speeds for each canopy layer (m/s)

z a vector of canopy node heights (m)

sz a vector of soil node depths (m)

zabove height of tabove. Here set to hgt

rh a vector of relative humidities

relhum relative humidity at 2 m above canopy (percentage)

tair air temperature at 2 m above canopy (deg C)

tsoil temperature below deepest soil layer. Same as input

pk pressure at 2 m above canopu (kPA)

Rabs Absorbed radiation (W / m^2)

gt Conductivity in air of each canopy layer node (mol/m^2/sec)

gv Leaf conductivity to vapour loss for each canopy layer node (mol/m^2/sec)

gha Conductivity between air and leaf for each canopy layer node (mol/m^2/sec)

H Sensible heat flux (W / m^2). Here set to zero

L Latent heat flux (W / m^2). Here set to zero

G Ground heat flux (W / m^2). Here set to zero

Rswin Incoming shortwave radiation. Here set to Rabs

Rlwin Incoming longwave radiation. Here set to 0.2 * Rabs

psi_m Diabatic correction factor. Here set to zero

Examples

paraminit(20, 10, 10, 15, 2, 80, 11, 500)

ilyamaclean/microclimc documentation built on July 28, 2023, 1:40 a.m.