Soil temperature at a lake_boundary point

[Fuhow]

Hi,

I am using the newest ctsm 5.3 now.

I ran a point grid simulation at a lake boundary, where PCT_LAKE = 35, and PCT_NATVEG = 65, I validated the soil temperature with TSOI vs observation, but accuracy was bad.

For TSOI is natveg and crop landunit only, I tried a land-cover-weighted temp: MIXT = 0.35TLAKE + 0.65TSOI, and accuracy got better.

My question is:

1. Is this weighted MIXT method reasonable for describing soil temp at the lake boundary point?
2. How do I set up 25 lake layers in CTSM 5.3? (10 lake layers defaultly)

Thanks for any tips!

 

[Fuhow]

After reviewing the technical note and the two code modules (LakeFlux and SoilFlux), I found that the flux calculations for lake columns and vegetation columns are relatively independent.

However, I am still curious about how to set 25 lake layers.

 

[oleson]

I'm not sure if this feature is working or has been tested, but in clm_varpar.F90, there is the following code:

    if (.not. use_extralakelayers) then
       nlevlak     =  10     ! number of lake layers
    else
       nlevlak     =  25     ! number of lake layers (Yields better results for site simulations)
    end if

So you could try setting user_extralakelayers = .true. in your user_nl_clm.
But in doc/IMPORTANT_NOTES it says that this namelist variable falls in the category of:

Namelist items that are not regularly tested or used. Some aren't even implemented.

 

[Fuhow]

I'm not sure if this feature is working or has been tested, but in clm_varpar.F90, there is the following code:

    if (.not. use_extralakelayers) then
       nlevlak     =  10     ! number of lake layers
    else
       nlevlak     =  25     ! number of lake layers (Yields better results for site simulations)
    end if

So you could try setting user_extralakelayers = .true. in your user_nl_clm.
But in doc/IMPORTANT_NOTES it says that this namelist variable falls in the category of:

Namelist items that are not regularly tested or used. Some aren't even implemented.

Hi, @oleson ,
Thanks for your response.
I have tried setting use_extralakelayers = .true. , but it will stop with an error of :
check_dim_size ERROR: mismatch of input dimension 10
with expected value 25 for variable levlak

Seems like the default levlak in src is 10.