compute_stomatal_conductance_jarvis: Canopy stomatal conductance by Jarvis.
In bgctw/etpart: Partitioning evapotranspiration into transpiration and evaporation

Description Usage Arguments Details Value References See Also Examples

Calculate canopy stomatal conductance using Jarvis's approach.

1	compute_stomatal_conductance_jarvis(par, Q, VPD, Tair, gcmax)

`par`	Set of parameter for the respective sensitivity function.
`Q`	Vector containing time series of photosynthetic active radiation (umol CO2 m-2 s-1)
`VPD`	Vector containing time series of vapor pressure deficit (kPa).
`Tair`	Vector containing time series of air temperature (deg C).
`gcmax`	Empirical parameter defining maximum conductance (m s-1 or mol m-2 s-1).

the following metrics are calculated:

compute_stomatal_conductance_jarvis <- gcmax*f(Q)*f(VPD)*f(Tair)

a numeric value: canopy leaf conductance (units refer to that given by gmax)

Perez-Priego, O., G. Katul, M. Reichstein et al. Partitioning eddy covariance water flux components using physiological and micrometeorological approaches, Journal of Geophysical Research: Biogeosciences. In press

partition_priego,

 ## Selecting a single day (e.g. 15-05-2010)
tz <- get_tzone(FIHyy$timestamp)
tmp <- FIHyy[(FIHyy$timestamp > ISOdatetime(2010,5,15,0,0,0,tz=tz)) &
             (FIHyy$timestamp <= ISOdatetime(2010,5,16,0,0,0,tz=tz)),]
gc = compute_stomatal_conductance_jarvis(par=c(200, 0.2, 25)
,Q = tmp$Q
,VPD = tmp$VPD/10 # convert hPa to kPa
,Tair = tmp$Tair
,gcmax = 1)
plot(gc ~ tmp$timestamp)