[MITgcm-devel] seaice dynamics in a 2-D set-up

[Jean-Michel Campin]

Hi Martin and others,

I am trying to run a simple oceanic 2-D (Y-Z) set-up with seaice dynamics.
It starts without seaice and before seaice forms the LSR solver
converges (not just doing 1 iteration, but within 10-12 iters).

But as soon as there is seaice, it stops converging and
more than half of the CPU time is spent in SEAICE_DYNSOLVER
(despite the fact that I have 50 levels + SOM advection scheme).

I can reduce the max number of LSR iterations (SOLV_MAX_ITERS),
faster but still not great.
I tried separatly SEAICEuseMultiTileSolver=T and SEAICE_OLx,y=1
but the improvement is very marginal.

I am tempting to reduce even more SOLV_MAX_ITERS but start to worry
about what the ice velocity will be.
Is there anything I could try ?
and should we think of some code modification for the specific case
where Nx=1 or Ny=1 ?

Cheers,
Jean-Michel