Ocean Modeling Discussion

The original focus on a spatially varying bottom roughness was to pattern it after bottom sediment maps and characteristic roughness lengths. It was felt that a more accurate representation of the bottom roughness would improve the predictability of ROMS within an esturary such as Delaware River and ...

I recopied myDBROMS.1 to myDBROMS.1.1 and removed the Build and Bin directories which I no longer needed. I modified the necessary routines and the makefile.robc.mpi worked perfectly.

I can only think that the diff did not pick up some minor character difference in the files which caused gmake to ...

I have successfully implemented this strategy and now have under myDBROMS.1 several /Bin and /Build files. With /Nonlinear I have several versions of set_vbc.F and use the makefile on the appropriate file.

I wanted to eliminate some of the /Bin and Build files, so I copied myDBROMS.1 to myDBROMS.2 ...

Is it possible to use LF95 compiler with ROMS in serial mode. Any suggestions would be much appreciated.

With the East and West Boundary Conditions corrected, Case 1 (in the initial post) ran successfully for both high flow and low flow 15 day hindcasts.

I wanted to add some additional information to clarify my initial post. I discovered a problem with my initial zeta boundary conditions. The East and West boundaries were switched.

On the west boundaries 1-57 are open ocean and from 57 to 550 all is land except for C&D canal at 166-167.

On the ...

John and Kate: Many THANKS for your replies. I know you both probably work differently with different software, but would each of you give me more information on exactly how you debug the code?

John.....I believe you write out the restart fields at more frequent intervals into the restart netcdf ...

With respect to the cppdefs for the snippets, it may be necessary to run the code in serial mode to facilitate the I/O. In the present ROMS, it looks like only the MASTER process can do the I/O.

What would be involved in implementing parallel I/O for the debug snippets?

With respect to the debug snippets, I was thinking along the lines of the following approach.

For each major cppdep option in the code, one writes a debug snippet, which is itself a cppdef option, which can be selected
to further diagnose problems.

For WET_DRY one has WET_DRY_SNIP to further debug ...

Thanks for the information, I will further study the problem.
As a general rule, as I understand your postings, if the model blows up Nans are generated for total energies and a restart file is written in netCDF, which probably contains a large number of Nans . As such it cannot be used to diagnose ...

I should have included _r8 after the 10.0 constants.

In diag.F, I believe one can add after:

Compute and report out volume averaged kinetic, potential
total energy, and volume.

In 3d inner loop:

if ( ABS(u(i,j,k,nstp)) .gt. 10.0 .or.
ABS(v(i,j,k,nstp)) .gt. 10.0)exit_flag=1

In 2d inner loop:

if ( ABS(ubar(i,j,krhs)) .gt. 10.0 .or.
ABS(vbar(i,j ...

I was wondering if the OBCS have been tested with all the different numeric options in the code. Is there a certain set of OBCs to use
for each set of numerics. Any information on this would be much appreciated.

FSCLAMPED Cases:

For all cases DT=20s ndtfast=20 with EAST, WEST, and SOUTH boundaries treated
the same. NORTH boundary is a solid wall. The following cpp options were used
for each of the FSCLAMPED open boundary cases.

ATM_PRESS Impose atmospheric pressure onto sea surface.
ANA_BSFLUX ...

Thanks....John.....I will follow this approach. When I had names such as
wrt_station.F and wrt_station.org.F, even though I touched wrt_station.F to make sure it was the most recent version and the one I wanted to use,
the makefile would create the sfmakedependcy file such that the wrt_station.org.F ...

I am adding two new cppdef options:

1. Z0_SVAR----spatially variable botton roughness, z0
2. MET_OUT----write wind and atm pressure to station and history files

To accomplish this I have had to modify several of the *.F files. I have for example set_vbc.F and set_vbc_org.F for the modified and ...

I am using ROMS 3.0 and have mpi turned on. I have a makefile called makefile.mpi which selects DELAWARE_BAY and within /Include/delaware_bay.h resides with some cppdef options.

I now have created a new application termed delaware_bay_robc.h (reduced open boundary conditions) in /Include. I wish to ...

Hi All,
Kate....Thanks for the picture. I am assuming that the netCDF files in ROMS read and write information only in the white area of the figure.
This also appears to be further documented in the C-grid figure within mod_param.F.

For RHO point information, one goes from 1, Lm and 1, Mm
Lm is ...

So are these diagrams correct?

------U(i,j)..................Rho(i,j).................U(i+1,j)
UFLOW..............Rmask(i,j)..............Umask(i+1,j)


------U(i,j)...................Rho(i,j).................U(i+1,j)
Umask(i,j)............Rmask(i,j)................-UFLOW

Where UFLOW is the ...

How are the u and v masks created from the rho mask. It appears that u and v masks are to the right and top of the computational stencil.



-----------UMASK(i-1,j).......RHOMASK(i,j).........UMASK(i,j)------------ Mask

Analogous for the VMASK with the role of i and j interchanged.

In the ...

In reviewing the code in diag.F, I note that if either the kinetic or potential energy summed over the domain is N or n or * (exceeds 8 places) then the exit flag 1 is triggered and the model Blows Up.

I will consider adding a supplemental check, whereby if either a u or v velocity component ...

Hi All,

As a new user to ROMS, I was wondering what the approach was to debug the model blowing up. I have recently been running an application for the Delaware Estuary and obtained:

ROMS/TOMS -Blows Up .....................exit_flag: 1
Saving the latest model state into RESTART file

MAIN ...

Thanks Kate....I have now modified the varinfo.dat file. I selected
Input/Output and would like to echo the bottom roughness field after it is read in, so I will work on that next. Thanks again....Dick

Hi....I am trying to add into ROMS a spatially varying bottom roughness, Zo. The approach is to develop this as a field similar to bathymetry within the grid generation procedure and include a field called zor at the model RHO points within the grid netCDF file. I have modified the following ...