Ocean Modeling Discussion

Jamie, thank you for your quick reply. Reading your note was a little confusing. I wondered if you have heard of the TR 1900x with 8 cores for about $500? It has four channels and runs a bit faster than the 1920x (same overclock numbers) but has less cache: L1/L2/L3 = 768K/4MB/16MB vs 1.125/6/32. I ...

Jamie This is great and very reasonable info. Thanks. I want to build a ROMS system for under or around $2k and was headed toward THreadRipper. Using PartsPicker I have been able to put together: Thread Ripper 1900, MSI 399 Motherboard, Corsair water cooling, DDR4 4x4k 3200 memory, Samsung 1Tb SSD ...

I am looking at residual diagnostic terms in a tidal application. I use a very strong low pass filter and the results, especially for u_accel are small compared to the tidal values. I get a very small negative bias on the u_accel term which becomes important in the residual. The bias is present in ...

Thank you for the references. However, they discuss the removal of tke due to the generation of new internal waves from turbulence (a process which has generated a major debate between those two groups). I am more concerned with additions to the effective eddy viscosity by unresolved internal wave ...

I am modeling a large tidal strait (Juan de Fuca) where the internal wave field is strong. I have been looking for a way to incorporate the impact of IW's in the eddy viscosity. Sukoriansky, et al. (NPG V13 pg 9) have recently proposed a scheme called Quasi-normal scale elimination (QNSE) which ...

I seems to me that the interpolation code for stations is shifting u and v by one node. For example, if you have a uniform x grid at 1km spacing, the value of u at the 8km station seems to be the average of values at 6.5 km and 7.5 km in the u grid (rather than 7.5 and 8.5). I see a similar thing ...

The code posted by CAE above matches what I came up with and it works for me as well. There are a couple of places in the .F file where it also needs #ifdef DIAGNOSTIS_TS so it won't get included if the diagnostics are not on. In working on this problem I also found that the diagnostics don't reset ...

I have been having similar problems with the T and S diagnostics. After looking at the code in step3d_t_tile, I think there may be a problem when the MPDATA option is set. In that case it looks like the basic horizontal and vertical advection terms are computed and summed without any calculation of ...

Hi Amanda
I had somthing similar where things built up beyond any value that was set at the boundary. I don't remember what it was, but I think I found it by looking at the detailed diagnostic output for tracers and seeing what the source was.

Wayne

I have the same situation, i.e. no surface forcing but a lot going on at the bottom. I have used a simple parabolic form: Cs = (1-s)^2 -1, without any problems. You can tweak the exponent to change the mix. However, I switched back to the standard formula just to stay in sync with other people ...

All the examples that come witH ROMS could be significantly more useful if the people who set them up would write a short note on why they chose the options that they did. For example, why choose one advection scheme over another for an estuary, or why use certain values of AkV_BAC. Why use SPLINES ...

I'll answer my own question, which mightl help someone else someday. I should have followed the basic rule: " when things look funny, increase the sampling rate." The wave motions which I thought I was seeing (and seemed to match what I expected) where aliased snapshots of an unexpected, much higher ...

I've got a bunch of simulations, some of which get pretty violent, where w and zeta don't seem to match. In a rectangular channel model I get a big standing wave across the channel which looks realistic except the surface is going up when w in the top layer is negative. Sometimes it seems to be ...

I have a question along these lines. Basically, What is the relationship/ interdependence between tidal forcing and the climatology codes. I have been doing a bunch of simple runs in a non-rotating, unstratified, rectagular channel just to understand how the tidal forcing and OBC's work. I am using ...

I am modeling tidal flows over rough topography, in particular the Strait of Juan de Fuca. I have been reading up on obc's and have found the literature dealing with conditions along a coast and without tides (Chapman, Marchesiello, Palma). Does anyone know of any quantitative evaluation of OBC's in ...

I've been working on what I think is a related problem I found that with more than one tidal component only the first one gets scaled, so for example, the angle of the ellipse, UV_Tangle, for the second component gets used in ROMS as degrees instead of radians. This is because the variable Npts in ...

I've just started using ROMS and wanted to use the stations output options. I don't see any references to this feature anywhere in the forum. Is it used much? Has anybody got a sample input file?

Thanks