Sensible Heat Flux Estimates

There are several quantities output by Cupid which describe the sensible heat flux from the plant-soil-atmosphere system. These are outlined here.

Sensible heat flux is always positive when heat is being tranported upwards (as opposed to soil heat conduction, where heat flux down into the soil is positive).

HCPY

HCPY is an output variable name - it is assigned the quantity QCOND(2) when it is written to file.

QCOND is computed in the subroutine profl2 as such:

qcond(jz)=akh(jz)*(tn(ihr,jz+1)-tn(ihr,jz))

where TN is the temperature profile through all the layers. This quantity describes the heat flux from the combined soil and canopy systems into the atmosphere.

HTOT

HTOT is HEATG(J) summed over all canopy layers
HEATG(J) is GHEAT(I,J) summed over all leaf angle classes
GHEAT(I,J) is HEAT(I,J)*DF*FRAREA(I,J)
HEAT(I,J) is 2400./RHLEAF(J)*DELT(I,J)
DELT(I,J) is the temperature difference between leaf and air as determined by the leaf energy balance equation.

This quantity describes the heat flux from the canopy alone.

HCPYS

This is the sensible heat flux from the soil into the canopy. If you add this to HTOT (the flux from the canopy to the atmosphere) you get HCPY:

HCPY = HTOT + HCPYS