ww3_multi.inp?

[benjamin-cash]

Could someone point me to documentation on how ww3_multi.inp is generated and what the time entries mean? Specifically I'm looking to understand lines like this:
line 17: 20130401 000000 10800 20130403 000000 1
The YYYYMMDD sections are presumably the start and end dates for the runs, but I'm not sure what to make of the 10800. Similarly:
line 641: 20130403 030000 3024000 20130403 030000
appears near the end of the file.

Thanks!

[JessicaMeixner-NOAA]

@benjamin-cash the line numbers are not helpful as you can have as many comment lines as you want.

There are example input files here:
https://github.com/NOAA-EMC/WW3/blob/develop/model/inp/ww3_multi.inp
that provide more documentation.

The 1 at the end of the line unfortunately is not yet documented in that file. I'm assuming that's for one of the output, likely gridded output which means you are outputting the file per time step. If you send the full file I'd be happy to explain them further, but in general those lines are:

TimeStart DT dt TimeEnd 1

Where Time start is a YYYYMMDD HHMMSS time format, for starting the output and the time end of the output is the same format. DT is the tilmestep in seconds for the output and the 1 means write each file individually instead of all together.

[JessicaMeixner-NOAA]

@benjamin-cash the 0 for the dt means that no output (this particular being output for the first stream of restarts w/out a date stamp in the name) for this will not be written. Again, to better understand how this file is created the best place to look is where this is created in the workflow, which starts here: https://github.com/NOAA-EMC/global-workflow/blob/feature/coupled-crow/scripts/exgfs_wave_prep.sh#L819

[benjamin-cash]

@JessicaMeixner-NOAA I have looked at that section of the code and I'm afraid that it hasn't helped me all that much. I can see there are a large number of variable substitutions, but unless I am just not seeing something there is nothing in that code to tell me what the variables mean or where they were substituted in the file. I spent some time trying to find $PARMwave/ww3_multi.${NET}.inp.tmpl, which seems like it should have that information, but couldn't find anything that matched that name format.

[JessicaMeixner-NOAA]

The $PARMwave/ww3_multi.${NET}.inp.tmpl is here: https://github.com/NOAA-EMC/global-workflow/blob/feature/coupled-crow/parm/wave/ww3_multi.gfs.inp.tmpl

Most of the parameters are defined either here: https://github.com/NOAA-EMC/global-workflow/blob/feature/coupled-crow/workflow/cases/prototype7.yaml#L71-L77 or here: https://github.com/NOAA-EMC/global-workflow/blob/feature/coupled-crow/workflow/defaults/wave.yaml

[benjamin-cash]

Ah, thanks! Ok, so it looks like the settings that I am still trying to understand are:
RST_BEG DTRST RST_END

From the code you pointed me to, it looks like RST_BEG is substituted as: $time_rst_ini. That variable seems to come from: $ymdh_rst_ini, which depends on ${RSTOFFSET}. ${RSTOFFSET} looks to depend on a number of other variables, some of which are coming out of a set of if-then statements and other dependencies that I don't think I have enough information to untangle. I think I may just need to get a sample set of 35-day run files in order to answer this.

[JessicaMeixner-NOAA]

You don't actually need a restart file from WW3 unless you are restarting something, so you can just set DT=0 for both and wet the YYYYMMDD to whatever you want. @jiandewang sent you a 35 day run input file.