Search found 6 matches

by dylanrs617
Tue Mar 25, 2025 5:46 pm
Forum: ROMS Discussion
Topic: LMD/KPP performance in river plume simulations
Replies: 3
Views: 5788

Re: LMD/KPP performance in river plume simulations

Thanks for sending this. I was unaware of the bug - but I am using COAWST v3.8, which has ROMS 4.1. I will need to see how difficult it is to git cherry pick the commit and deal with merge conflicts.

That said, I don't think GLS is overmixing in this case (recall I paired it with harmonic lateral ...
by dylanrs617
Sun Mar 23, 2025 8:09 pm
Forum: ROMS Discussion
Topic: LMD/KPP performance in river plume simulations
Replies: 3
Views: 5788

Re: LMD/KPP performance in river plume simulations

Just for an update, I found significant improvement with Richardson number smoothing paired with biharmonic mixing. See attached for a vorticity comparison with the same GLS simulation (that uses harmonic).

kpp_w_biharmonic_RI_smooth.png

RI_HORAVG Smooth Richardson number horizontally
RI ...
by dylanrs617
Fri Mar 21, 2025 3:51 pm
Forum: ROMS Discussion
Topic: LMD/KPP performance in river plume simulations
Replies: 3
Views: 5788

LMD/KPP performance in river plume simulations

Hi All,

I'm doing a model-model comparison of the Texas-Louisiana shelf with ROMS and MPAS-O. Our ROMS model is validated (Hetland 2017 JPO, Kobashi & Hetland 2020 OD) and normally uses k-omega or k-epsilon for vertical mixing with great success. The mean resolution is ~1.5 km. 30 vertical layers ...
by dylanrs617
Thu May 23, 2024 3:49 pm
Forum: ROMS Discussion
Topic: Question about Smagorinsky mixing coefficients
Replies: 0
Views: 9449

Question about Smagorinsky mixing coefficients

Hi All,

I'm doing some experiments with Smagorinsky viscosity/diffusion applied biharmonically along geopotential surfaces to explore its impacts on numerical mixing. In hmixing.F, I see that Bsmag is controlled by PecletCoef, which is equal to 1/12. Where does the 1/12 come from? It's unclear to ...
by dylanrs617
Tue Jul 25, 2023 7:43 pm
Forum: ROMS Discussion
Topic: DIAGNOSTICS_TS in step3d_t
Replies: 3
Views: 7753

Re: DIAGNOSTICS_TS in step3d_t

A little late, but I believe you're correct. Parker MacCready posted a thread about this about a decade ago, it gets at this issue as well. Took me too long to figure out myself until I discovered that thread, posting this to help aggregate.


I figured out the problem with my salt_rate test. salt ...
by dylanrs617
Tue Jul 25, 2023 7:20 pm
Forum: ROMS Discussion
Topic: Calculate tracer vertical diffusion coefficients offline?
Replies: 0
Views: 8793

Calculate tracer vertical diffusion coefficients offline?

Is it possible to calculate the vertical tracer diffusion coefficients "AKt" or "AKs" offline with model output? I'm using the GLS k-epsilon vertical mixing scheme for context and would appreciate if there's a way to compute them using the model equations.

I'd like to construct an offline ...