[MITgcm-support] Stratification simulations

[David Hebert]

Hi all,

I have run two identical simulations, one with a constant temperature 
field, and one with temperature gradient specified via tRef array. The 
simulations are run in non-hydrostatic mode. When I compute the vertical 
velocity fields, and consequently vertical KE = 0.5 w^2, the results are 
identical.

I have checked the temperature field and indeed there is a temperature 
gradient. Also, the diagnostic DRHODR and there is a value there for 
each vertical level of -0.0408. However, the diagnostic RHOAnoma and 
RHOANOSQ are all zeros. It seems as if the density stratification does 
not affect the flow. I have turned on the tempForcing flag. Are there 
any flags in the datafile that should be turned on?

Other notes/questions:
1) I turned tempStepping off because I wanted a constant gradient just 
to demonstrate effects due to stratification. Should this be turned on?
2) Do I need to have an initial temperature field to obtain a RHOAnoma 
value, since it is RHOAnoma is used in the code
3) My domain is small, 480x160x160m^3. Grid resolution 1m. Velocity max 
= 0.2 m/s. Simulations integrated with dt=1s for 10800 seconds.
4) I have been looking through src/calc_gw.F and don't see a gravity 
term. Could someone point me to where is the gravity term introduced 
into the model? Is it in correction_step.F? I see something in 
calc_buoyancy.F, but I do not see where CALC_BUOYANCY is being called from.

Any help in setting up the model for stratification is greatly 
appreciated. Thank you much,

David