Ocean Modeling Discussion

Hi,

I had a similar issue some time ago, releasing a passive tracer into operational simulations at t = t0 + 1 day. I solved this by modifying some code in step3d_t.F, following the suggestions given in https://www.myroms.org/forum/viewtopic. ... 969#p22969.

Best regards,

Marc

Thank you, John and Gaoyang, I will look into the bottom friction characterization. The bathymetry within the estuary is interpolated from a set of rather high-resolution field data, so I don't think the problem will be due to that, but I will bear it in mind just in case.

M

Dear all, I am having an issue with tides in my simulations that I don't understand since I am no tides expert. I am modelling a South American Pacific estuary using a ROMS-only COAWST implementation on a three-grid nested scheme, forced at the outer boundaries by the CMEMS Global product and at the ...

If I set the nudging coefficient to 86400/DT, I get an "initial" concentration at time T that is close enough (approxs. 99.5%) to the value I've specified in the clm file. This is fine for my purposes.
Again, thank you very much for your help!

Hi again, I finally got round to doing this, following John's instructions in a previous post. a) I added some code in step3d_t.F that switches on the passive tracer nudging N timesteps before the time T I want it released, trying to keep N as small as possible. b) I use a nudging.nc file in which I ...

MPDATA did the trick for the tracer concentration over/undershooting. Thanks, John and Ivica.

Seems I was a bit too optimistic with the "normal" use of the tracer part, i.e., releasing the tracer at t = 0 day. I have been doing (sucessful) preliminary tests with ROMS 3.7, releasing a passive tracer with C = 100 (units) in a specific area of my domain, and C = 0 elsewhere. The tracer then ...

Thank you very much for your help, John. I will have a go at modifying step3d_t.F following your indications as soon as I can.

I know this is not done often, but how about saving the velocity and eddy diffusivity often enough to do the Eulerian computations offline? It will require some coding of course but given the lack of better options ... is there a reason this will not work? (Especially if only interested in the sea ...

John, Thank you, but if possible I'd rather not use Lagrangian floats. I want to obtain a spatial distribution of the flushing time in the waterbody, and I think a Eulerian approach is better suited for this, Searching through the forum and the cppdefs.h file I see that perhaps I could achieve what ...

Thanks Kate. Yes, it would. I am adding the flushing time component to an already established operational system that runs four-day long simulations (i.e., one day hindcast+three days forecast) in a large number of domains. The flushing time calculation will only apply to one of these domains ...

Hi all, I am trying to calculate water e-flushing times in a semienclosed basin according to Jouon et al.'s (2006) definition, which involves seeding the wet nodes of the domain with a Eulerian tracer and seeing how it evolves in time. Everything is fine if I want to introduce the tracer at t = 0 ...

Hi, I am trying to run a COAWST ROMS-only simulation as a first step to a coupled ROMS-SWAN scheme. My BCs are provided in 6 files that are specified in the *.in file following the usual ROMS format (i.e, each filename in a separate line, followed by a vertical line "|", except the last one), and I ...

Hernan and John

Thank you very much. Will try it as soon as possible.

Regards

Thanks John. I have followed your suggestion and repeated the nesting using a factor of 3 for both refinements, but the problem remains. I can bypass it by manually invalidating the contact regions between the finest and coarsest meshes in the grid_connections routine, but it still bothers me since ...

I am trying to generate the contact file for a setup with three telescoping grids. Grid A fully contains grid B, which in turn fully contains grid C, similarly to the ADE nesting in the Lake_jersey test case (which I have managed to replicate). Both nested grids have been generated using the ...