[MITgcm-support] Warm start and cold start yielding same results

[kunal madkaiker]

Dear All,

I am trying to setup the physical model in north Indian Ocean in order to
study the mesoscale eddies, using warm start as well as cold start.

In warm start, Initial conditions of T,S come from WOA18 and U,V from SODA.
Boundary conditions of T,S,U,V are from SODA and ext. forcing from ERA5.
For cold start, setup is same except initial velocities are zero. Timestep
is 120s and spatial resolution is ~5km. I am running model for 30 days as
of now (doing monthly climatological simulations). Lateral boundary is from
west, east and south.

Both the simulations: warm and cold start is yielding the same results in
terms of current, temperature etc. and I am not seeing any significant
effect of the initial velocities in the warm start simulation. My
understanding is that somehow the boundary conditions are nullifying the
effect of initial velocities, but I am not understanding why that might
happen.

Kindly provide some suggestions. Let me know if anything is wrong from my
end.

Also, I would appreciate some help in setting the OBCS balance values.
Currently, I am balancing individual boundaries by giving value as -1. The
flow pattern in my domain is such that, during summer monsoon (JJAS) water
flows from Arabian sea to bay of bengal (west to east) and vice versa
during winter monsoon (OND).

Attaching some plots and my namelists. Apologies for the long email.

Thanks and Regards
Kunal
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