question about canopy conductance

[yfang]

Hi,
I'm trying to calculate canopy conductance Gc for each grid cell of a global simulation. Is it ok to use the mean conductance over multiple pfts as effective Gc for a grid assuming it's controlled by a dominant pft?

 

[oleson]

I don't know what your research needs are, but some gridcells are likely to have significantly mixed pfts within them. An alternative is to output the conductance at the pft-level.

 

[yfang]

@oleson Thanks for your input! I am not aware of a history variable for pft-level Gc. Can I add the variable calculated in the following code to the history fields https://github.com/ESCOMP/CTSM/blob...57e/src/biogeophys/CanopyFluxesMod.F90#L1132?

 

[yfang]

I'm trying to find Gc ~ VPD relationship.

 

[oleson]

You would add it as a history variable in subroutine InitHistory in biogeophys/EnergyFluxType.F90. By default, it will come out as a gridcell average variable. But you can specify pft-level in your user_nl_clm as a separate history stream by setting dov2xy=.false. for that stream.