Single point surface data

[Mesmer]

hi, everybody, i want to know if it is possible to tell to the clm5.0 that a part of my surface is made by roc. u know when u go to the mountain some part of the areas are rocky.

thanks

 

[oleson]

CLM5 uses a depth to bedrock dataset that you could manipulate. See section 2.2.2.2 here for a description:

2.2. Surface Characterization, Vertical Discretization, and Model Input Requirements — ctsm release-clm5.0 documentation

The relevant variable on the surface dataset is zbedrock. I believe there is a minimum depth to bedrock of 0.4 m.

Alternatively, you could give the soil layers rock-like thermal and hydraulic properties.

 

[Mesmer]

thanks , i never do this u can explain me in a better way how to do this: Alternatively, you could give the soil layers rock-like thermal and hydraulic properties.

 

[oleson]

Look at section 2.6.3 in the CLM5 technical note to see how thermal properties are prescribed:

2.6. Soil and Snow Temperatures — ctsm release-clm5.0 documentation

escomp.github.io

Look at section 2.7.3.1 to see how hydraulic properties are prescribed:

2.7. Hydrology — ctsm release-clm5.0 documentation

The soil properties are set in:

src/biogeophys/SoilStateInitTimeConstMod.F90

In thinking more about this, perhaps you could follow the example of "impervious road" for the urban landunit. The top few layers of impervious road have thermal properties that correspond to concrete or asphalt.

For impervious road the "soil" properties are overwritten in:

src/biogeophys/SoilTemperatureMod.F90

You'd have to find a way to turn off the hydrology for the rock, perhaps by not allowing any infiltration, as is done for impervious road.