FAQ: Data ocean slab mode (DOCN-SOM)

[dbailey]

Boundary layer depth (turbulent mixing based) seemed more physical than an arbitrary depth based on the density or temperature gradient.

 

[michelle_dvorak]

Hi Dave, thanks for your help so far. Like some others I have a question about achieving a stable equilibrium ocean temperature in a SOM setup. I am runing an 1850_CAM60_CLM50%SP_CICE_DOCN%SOM_MOSART_SGLC_SWAV compset with CESM2.1.3, and using the
pop_frc.b.e21.B1850.f09_g17.CMIP6-piControl.001_branch2.012120.nc forcing file from the inputdata directory.

After 30 years of simulation I'm still getting a steady warming (about 0.05 degrees C per year in global average SST). I'm wondering:
a) If I just need a longer spinup time to reach a steady state
b) If there is a mismatch between my configuration and the configuration that the forcing file is derived from
c) If it would be appropriate to apply a global offset to the forcing file to attempt to compensate for the energy imbalance

Any advice you have would be very helpful, thanks!

I'm curious about this. I've been using the same forcing files in my simulations -- with some local modifications.

Do we know if pop_frc.b.e21.B1850.f09_g17.CMIP6-piControl.001_branch2.012120.nc is the best option for a CESM2 preindustrial control slab ocean run?

A TOA imbalance of 0.15 Wm-2 does not seem negligible.

Michelle

 

[dbailey]

This one is from a retuned sea ice albedo run (Kay et al. 2022). So, it might be off because you are using the out of the box sea ice tuning. I would recommend setting the following in user_nl_cice:

r_snw = 1.50
dt_mlt = 1.00

This might help with the TOA a bit. After how many years did you evaluate the TOA? Might have to run at least 30 years before it starts to come down.