Forcing nesting suite with ERA5

On further reflection - this may not be quite right

The models is expecting lbcs each hour (rg01_rs01_m01_lbc_freq=3600s), so for the 12 hr cycle there should be 12 times in the lbc file, but there is only one time.

(does the model interpolate to get hrly lbc updating)

Hi Grenville,

I haven’t changed anything in um_createbc from the default settings, and can’t see whether it does any interpolation in time - do you think it is a matter of adjusting the rg01_rs01_m01_lbc_freq=43200 and CRUN_LEN to match the output frequency of the input era data (i.e. 12 hours)?

I’ve given that a whirl and submitted it, but it hasn’t started running yet…


can you supply ec_cb000 ec_cb012 ec_cb024 ec_cb036 ec_cb048 type files, but at 6hrly intervals?

Hi Grenville,

Unfortunately the ERA5 data I have is only every 12 hours, for December 2000 only. If there’s an alternative 6-hrly source on archer that includes all the fields required to force the model, I could try that…? Do you know if there is another place where era5 sits on disc?


Hi Ella

I see that you changed to lbcs each 12 hrs & that produced a more sensible lbc file. We never got to the ancil problem. It might help if you switch off packing - that way there is a chance to see which field is causing problems.


Hi Grenville, I did turn the stashpacking off and am now getting some different errors about the recon. It’s complaining about the topographic index ancils:

[FAIL] namelist:items(7ea74479)=ancilfilename: UM_ANCIL_LSH_TOPIND_DIR: unbound variable

I originally didn’t have these set up to reconfigure because I didn’t think they were necessary but I added them in because initially I was getting this same error in the um_rs01_rg01_fcst step. I noticed this namelist entry file in app/um/opt/rose-app-ra3_pack3.conf so assumed it was necessary for the RA3 config I’m using:

> # #84 land consolidation package
> [namelist:items(4786818a)]
> domain=1
> !!interval=1
> l_ignore_ancil_grid_check=.false.
> !!netcdf_varname='unset'
> !!period=1
> source=2
> stash_req=274,275
> update_anc=.false.
> !!user_prog_ancil_stash_req=
> !!user_prog_rconst=0.0

I re-ran the global recon so that the inner domain would pick up the changes from there but am now getting the error in the ec_recon.

I can’t figure out whether this means I should have it in or out, as it seems to complain either way.