Search found 17 matches

by apaloczy
Tue Jun 02, 2015 4:38 am
Forum: ROMS Discussion
Topic: Publications on M2 diagnostics
Replies: 2
Views: 987

Re: Publications on M2 diagnostics

Thanks jcwarner, these are really helpful.
by apaloczy
Mon Jun 01, 2015 11:08 pm
Forum: ROMS Discussion
Topic: Publications on M2 diagnostics
Replies: 2
Views: 987

Publications on M2 diagnostics

Hi,

Does anyone know of publications that specifically discuss the terms from the depth-averaged momentum (M2) diagnostics in their analyses? All the references I found so far seem to use only the M3 diagnostics.

Thank you!
by apaloczy
Wed Jul 30, 2014 3:18 pm
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Hi hugobastos, thanks for your reply. This plot of maximum points is a single point, or is the maximum in every timestep? I'm thinking that you probably used the maximum per timestep, which indicates that the location of the point can be varying right? Yes. My tip is that after the ~50day, the point...
by apaloczy
Fri Jul 18, 2014 12:55 am
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Updates: I capped the topography at 1200 m instead of at 2000 m, keeping everything else the same, and the HPGE decreased from 10-30 cm/s to ~3 cm/s. Also, the sudden acceleration to ~40 cm/s in the first 5 days is gone. The HPGE now increases more smoothly (attached). After day ~50, weird banded st...
by apaloczy
Tue Jul 15, 2014 4:26 pm
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Thanks mastrorocco and hugobastos for bringing this vertical coordinate issue to my attention. It seems like a very good source of trouble. don't know why you are using Tcline = 0 and I am not sure if this is fine (perhaps someone else can comment on that!). I set Tcline to 0 in order to minimize bo...
by apaloczy
Tue Jul 15, 2014 2:12 pm
Forum: ROMS Problems
Topic: Diagnostics don't add up!
Replies: 10
Views: 4716

Re: Diagnostics don't add up!

Thanks for the reply, rduran. That doesn't seem too bad to me, if you were working with single precision (you are probably using double precision, but just to make a point) then that would be zero. It would still be good to know why its not more like 16 orders of magnitude (zero in double precision)...
by apaloczy
Mon Jul 14, 2014 4:45 pm
Forum: ROMS Problems
Topic: Diagnostics don't add up!
Replies: 10
Views: 4716

Re: Diagnostics don't add up!

Hi rduran, thanks for your suggestion. I looked at the ratio of the residue and the leading term, and the ratio of the residue and the smallest term. The ratios between the residue and the leading term show that the residues are everywhere 9-7 orders of magnitude smaller than the leading terms. The ...
by apaloczy
Mon Jul 14, 2014 2:19 pm
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Thanks jivica, this procedure seems very useful. I will follow that in another application where I'm seeking a realistic topography. But in this application with idealized topography, I don't understand why I'm getting this much HPGE with this configuration. I'm using safe rx0 and rx1 values (0.075 ...
by apaloczy
Sat Jul 12, 2014 12:42 am
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Got it, saulo. I will fiddle with the grid a little more to decrease rx1. So based on the information I found so far and considering that I have tried pretty much everything, it looks like my slopes are just too steep. At least the largest errors are not located around the shelfbreak, which is the a...
by apaloczy
Sat Jul 12, 2014 12:27 am
Forum: ROMS Problems
Topic: Diagnostics don't add up!
Replies: 10
Views: 4716

Re: Diagnostics don't add up!

rduran, did you figure out why the momentum balance terms didn't add up? I am having the same problem. I am computing the following sums for the 2D and 3D momentum balances, respectively (and analogously for the xi-direction balance): residue_2D = vbar_hadv+vbar_cor+vbar_prsgrd+vbar_sstr+vbar_bstr+v...
by apaloczy
Fri Jul 11, 2014 5:45 pm
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Thanks everyone for your replies. Following Ianerolle's suggestion, I did two test runs changing only the vertical stretching curve as depicted on my previous post. It seems that, for my application, the configuration with Vtransform = 2 and Vstretching = 4 produces less Horizontal Pressure Gradient...
by apaloczy
Thu Jul 10, 2014 3:17 pm
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Re: Near-bottom numerical instability over the slope

Hi Ianerolle, thank you for your reply. With the parameters you suggested, the vertical stretching curve becomes the red line in the attached figure. The maximum Haney number rx1 increases from 3.7 to 14.1: (ORIGINAL) N, theta_b, theta_s, tcline: 50.0, 0.0, 0.0, 0.0 (MODIFIED) N, theta_b, theta_s, t...
by apaloczy
Wed Jul 09, 2014 4:52 am
Forum: ROMS Problems
Topic: Near-bottom numerical instability over the slope
Replies: 16
Views: 5959

Near-bottom numerical instability over the slope

Hello all, I'm having problems with pressure gradient errors over an idealized continental slope application. My initial field is just flat stratification, with an N2 profile derived from a climatological dataset. I have baroclinic (barotropic) velocity errors of 10 cm/s (4 cm/s) after a steady-stat...
by apaloczy
Thu May 01, 2014 6:16 pm
Forum: ROMS Tools and Techniques
Topic: bathy_smoother submodule problem
Replies: 0
Views: 1109

bathy_smoother submodule problem

Hello, I am having trouble using the LP_smoothing_rx0() and LP_smoothing_rx0_heuristic() functions of the bathy_smoother submodule of pyroms. It seems that I have built and installed bathy_smoother, lp_solve and lpsolve55 (with its python component) successfully, since bathy_smoother imports the lps...
by apaloczy
Tue Apr 15, 2014 10:57 am
Forum: ROMS Usage
Topic: Construction of forcing file (stationary forcing)
Replies: 5
Views: 2778

Re: Construction of forcing file (stationary forcing)

Understood, Arango. It seems that ticket was just before I started learning ROMS. Thanks.
by apaloczy
Thu Apr 10, 2014 11:53 am
Forum: ROMS Usage
Topic: Construction of forcing file (stationary forcing)
Replies: 5
Views: 2778

Re: Construction of forcing file (stationary forcing)

Hi Ivica, thanks for your reply.

Your suggestion seems to be better than the "cycle_length" approach I was using. Now that I have made this change, GET_2DFLD is reading the forcing file only once, and not every time step as was happening before.

Thanks,
by apaloczy
Thu Apr 03, 2014 12:41 am
Forum: ROMS Usage
Topic: Construction of forcing file (stationary forcing)
Replies: 5
Views: 2778

Construction of forcing file (stationary forcing)

Hello, I am new to ROMS, and would like to know whether I am setting the time dimension of the forcing variables correctly. sustr and svstr are given at a single time, and I want them to be applied at every time step. It appears that the routine get_2dfld.F is reading the forcing file properly, but ...