I am running the WRF model at a low resolution (Dx=75000), having run at higher resolutions with success (DX=10000,27000). However, the wrf output file is only 37MB. It seems to be stopping at the first timestep. I attach the nameless file and a copy of the rsl.out file. I'm not really sure what is wrong here. I am pretty inexperienced!
WRF errors
- Thread starter rjhall
- Start date
Hello! It looks like you're running into CFL errors immediately. Essentially, the model may become unstable when the Courant number (C) is greater than one, where C is:
C = (velocity*dt)/(dx).
The velocity here would be the wind. What happens when CFL is violated and C > 1 is that information from one gridpoint is travelling past the surrounding gridpoints in a single time step, which dynamic systems are not prepared to handle. This can happen if your time step is too large, or if there is especially strong wind in your simulation (including because of complex terrain).
The first thing to modify for CFL errors is typically the time step. It looks like your time step is set to 360. I would personally reduce that in steps of 30 or so and rerun until you find a time step that allows the simulation to complete. If that doesn't happen, or the functional time step is too small for your purposes, I would take a look at some of the various smoothing parameters. There are a few ways to control how waves are damped or even to smooth your terrain, but first you should probably take look at the time step.
One other error that someone new may run into is having incorrect boundary conditions, either from not running real.exe or having something go wrong upstream in WPS. If the boundary conditions are from the incorrect date or for the wrong domain, the extreme gradients at the boundary can sometimes cause CFL to be violated.
C = (velocity*dt)/(dx).
The velocity here would be the wind. What happens when CFL is violated and C > 1 is that information from one gridpoint is travelling past the surrounding gridpoints in a single time step, which dynamic systems are not prepared to handle. This can happen if your time step is too large, or if there is especially strong wind in your simulation (including because of complex terrain).
The first thing to modify for CFL errors is typically the time step. It looks like your time step is set to 360. I would personally reduce that in steps of 30 or so and rerun until you find a time step that allows the simulation to complete. If that doesn't happen, or the functional time step is too small for your purposes, I would take a look at some of the various smoothing parameters. There are a few ways to control how waves are damped or even to smooth your terrain, but first you should probably take look at the time step.
One other error that someone new may run into is having incorrect boundary conditions, either from not running real.exe or having something go wrong upstream in WPS. If the boundary conditions are from the incorrect date or for the wrong domain, the extreme gradients at the boundary can sometimes cause CFL to be violated.
Thank you. I decreased the time steps in steps of 30 as you suggested. Setting a timestep 0f 240 removed the CFL errors but the run still terminated almost immediately. (See attached rsl.out). So I am none the wiser and not sure where or what the smoothing parameters are. real.exe is run and the domain seems OK.
Looks like the additional smoothing won't be necessary, then! As for the new issue, I'd also like to see the rsl.error file if you have that available. I'd also re-run real.exe, if you haven't done that yet, and see if that changes anything.
A couple additional questions:
1) Are you getting any output files?
2) If you are running wrf by submitting a job to a cluster using a scheduler (like slurm), do you have output/error files from those jobs?
3) On a related note, is it possible that you are running out of memory for your job? If you can, try running with an increased number of cores or increasing your memory allocation.
A couple additional questions:
1) Are you getting any output files?
2) If you are running wrf by submitting a job to a cluster using a scheduler (like slurm), do you have output/error files from those jobs?
3) On a related note, is it possible that you are running out of memory for your job? If you can, try running with an increased number of cores or increasing your memory allocation.
Hi
Thanks for your efforts with this. Running real.exe again makes no difference. I get an output file but it is only 37MB, and it doesn't run long enough to get the wrfrst files.
The rsh. error files look the same to me but I attach one. From the job script output it looks like the job is being killed for some reason. I have tried different numbers of cpus.
Thanks for your efforts with this. Running real.exe again makes no difference. I get an output file but it is only 37MB, and it doesn't run long enough to get the wrfrst files.
The rsh. error files look the same to me but I attach one. From the job script output it looks like the job is being killed for some reason. I have tried different numbers of cpus.
William.Hatheway
Well-known member
Can you attach all your rsl.out and rsl.error files after you run ./real.exe
I am trying to run the coupled WRF/WRF-Hydro model with the Crocus option enabled. i have completed upto ./real.exe process and generated threre three files wrfinput_d02,wrfinput_d01, wrfbdy_d01. But now I am encountering a segmentation fault (core dumped) error while executing ./wrf.exe. I have generated all the required WRF-Hydro input files using the WRF-Hydro GIS Preprocessor with geo_em.d02.nc. The files I createdinclude: fulldom_hires.nc, GEOGRID_LDASOUT_Spatial_Metadata.nc, GWBASINS.nc, GWBUCKPARM.nc, hydro2dtbl.nc, Route_Link.nc,soil_properties.nc
I placed all these files in the WRF run directory with the Domain folder. However, when I execute mpirun -np 1 ./wrf.exe i got the error
(ncl_env) sagar@sagar-OptiPlex-Tower-Plus-7010:~/data/coupled_wrfhydro_Copy/WRF/run$ mpirun -np 1 ./wrf.exe
starting wrf task 0 of 1
===================================================================================
= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
= PID 18119 RUNNING AT sagar-OptiPlex-Tower-Plus-7010
= EXIT CODE: 139
= CLEANING UP REMAINING PROCESSES
= YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
===================================================================================
YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Segmentation fault (signal 11)
This typically refers to a problem with your application.
Please see the FAQ page for debugging suggestions
I have attached the error log files along with my namelist.input and hydro.namlist.
Could you please help me identify what might be causing this issue and what should be the namelist.input and hydro.namelist for two domains? I would greatly appreciate your guidance.
Regards
Sagar Lamichhane
I placed all these files in the WRF run directory with the Domain folder. However, when I execute mpirun -np 1 ./wrf.exe i got the error
(ncl_env) sagar@sagar-OptiPlex-Tower-Plus-7010:~/data/coupled_wrfhydro_Copy/WRF/run$ mpirun -np 1 ./wrf.exe
starting wrf task 0 of 1
===================================================================================
= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
= PID 18119 RUNNING AT sagar-OptiPlex-Tower-Plus-7010
= EXIT CODE: 139
= CLEANING UP REMAINING PROCESSES
= YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
===================================================================================
YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Segmentation fault (signal 11)
This typically refers to a problem with your application.
Please see the FAQ page for debugging suggestions
I have attached the error log files along with my namelist.input and hydro.namlist.
Could you please help me identify what might be causing this issue and what should be the namelist.input and hydro.namelist for two domains? I would greatly appreciate your guidance.
Regards
Sagar Lamichhane