Diagnostic for BGC modules in z* space

[ThomasNeumann]

Hi All, how one can setup the diagnostics of BGC modules (e.g. COBALT, ERGOM etc) in z* space. I am using MOM6, dereived from MOM_examples repository, with ALE and z* as target grid. MOM_input NUM_DIAG_COORDS seems to work for the ocea_model_z but not for generic_tracers in the BGC modules? Or did I got it wrong?

Thanks, Thomas.

 

[andrew-c-ross]

Hi Thomas, in the compiler flags you use to compile MOM6, do you include -D_USE_MOM6_DIAG? This flag will use the MOM6 diagnostic routines rather than the FMS routines for the BGC modules, which should enable writing remapped diagnostics.

 

[ThomasNeumann]

Thanks Andrew, no, I didn't used this CPP option so far. I will try it out and give a reply whether it solves the problem. I am still struggling getting the ERGOM BGC model running correctly. The runoff alkalinity, nutrients etc do not enter the ocean. I can see it in the diagnostics, e.g.
"generic_ergom","runoff_flux_t_alk","runoff_flux_t_alk", "ocean_sfc", "all",.true.,"none",2
but int the river mouthes , the concentrations become more and more diluted. For salt it works fine. Is there also a trick which will do it?
I looked up your Zenodo repository und found that some files in ocean_BGC (generic_tracer*) and also MOM/tracer differs from the repository MOM_examples where I got my MOM from. I will try out your code now, perhaps it solves the riverine input problem.
Cheers, Thomas.

 

[ThomasNeumann]

Hi Andrew, with -D_USE_MOM6_DIAG, the BGC tracer are available in z* space, thanks again.

 

[andrew-c-ross]

For the runoff problem, can you check if your ocean_BGC generic_tracer_utils code has this change and your MOM6 code has this change (or your code has neither change)? These fixes were added to avoid multiple counting of tracer inputs from runoff. I think it would fail to compile if you had the MOM6 change but not the generic_tracer_utils change, but if it did compile I think it would stop putting in tracers from runoff.