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There is a problem with the sensible heat flux and latent heat flux near the ground simulated by CLM5.0

zqzq

zqzqzqzq
Member
Dear all,
I have successfully simulated the near-surface latent heat flux and latent heat flux through CLM5.0, and now it involves the improvement of the parameterization scheme, but I have not yet figured out how to start.Under this folder /es01/paratera/sce0489/cesm2.2/my_cesm_sandbox/components/clm/src/biogeophys,Which specific file do I need to modify? Are there any good suggestions, thank you, my simulation results are shown in the attached picture.
 

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oleson

Keith Oleson
CSEG and Liaisons
Staff member
The attachment is too blurry to read/understand. Can you attach a picture with better resolution?
Have you included net radiation in your plots as previously suggested?
 

zqzq

zqzqzqzq
Member
The attachment is too blurry to read/understand. Can you attach a picture with better resolution?
Have you included net radiation in your plots as previously suggested?
Yes, net radiation is included,The problem now is that I want to modify the corresponding parameterization scheme, I guess the reason for the large simulated value of the near-ground sensible heat flux is due to the aerodynamic impedance, again I could not find the folder to modify the corresponding parameter in clm5, and I have no supporting information to use, do you have any suggestions?
 

zqzq

zqzqzqzq
Member
Yes, net radiation is included,The problem now is that I want to modify the corresponding parameterization scheme, I guess the reason for the large simulated value of the near-ground sensible heat flux is due to the aerodynamic impedance, again I could not find the folder to modify the corresponding parameter in clm5, and I have no supporting information to use, do you have any suggestions?
 

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zqzq

zqzqzqzq
Member
What is being plotted in (a) and what is being plotted in (b)? The legends and axis labels are not in English.
A description of the parameterizations for sensible and latent heat fluxes are in the technical note:


Most of those parameterizations can be found in CanopyFluxesMod.F90
Fig. (a) shows the near-surface sensible heat flux and Fig. (b) shows the near-surface latent heat flux, the black line represents the observed values, the red line represents the simulated values of CLM, and the x-axis is time. From the figure, we can see that the simulated value of CLM for sensible heat flux is large, what do you think is the reason for this?
 

zqzq

zqzqzqzq
Member
Fig. (a) shows the near-surface sensible heat flux and Fig. (b) shows the near-surface latent heat flux, the black line represents the observed values, the red line represents the simulated values of CLM, and the x-axis is time. From the figure, we can see that the simulated value of CLM for sensible heat flux is large, what do you think is the reason for this?
Do you have a tutorial or technical manual on how to modify the details of the parameterization scheme?
 

oleson

Keith Oleson
CSEG and Liaisons
Staff member
Could be that there is not enough moisture or vegetation to support a strong enough latent heat flux according to observations and so the net radiation is partitioned into more sensible heat. You could look at the components of latent heat flux (canopy evaporation, ground evaporation, transpiration) to see how those are behaving.
We don't have any tutorials or technical manuals on how to modify the details of the parameterization scheme other than the materials I have mentioned. It is a matter of studying the technical note with the code in combination to understand the processes and free parameters.
 
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