Opened 5 years ago

Closed 5 years ago

#1788 closed help (answered)

Wrong vertical levels in output?

Reported by: lboljka Owned by: um_support
Component: UM Model Keywords:
Cc: Platform: ARCHER
UM Version: 8.6



I have been trying to output my model results on the model levels, but they look very weird. My job is xlyyj.

I have the vertical levels file in which the (i.e. theta) levels should start with 0, 15.6, …. (simply multiplying top level - 32km with eta level stated in vertical file). However, when I output my variables (as requested in STASH) the model somehow changes the numbers of these rho and theta levels to (i.e. for theta) 0, 176.5 , … which is very different. I have no orography in the model as I am using Held-Suarez setup. What is even weirder is that in the dump file the levels are the same as in the vertical levels file, but in the data that I need, there is something wrong. The same problem occurs with rho levels.

My vertical levels file is in

archer$ /work/n02/n02/lboljka/Held_Suarez/vertlevs_L63_32km

My output files are in

archer$ /work/n02/n02/lboljka/um/xlyyj/

with names:

 xlyyja.pj20090112 ; xlyyja.pk20090112

And the dump file is in:

archer$ /work/n02/n02/lboljka/um/xlyyj/xlyyja.da20090212_12

I am worried that the vertical levels that I have in the *.pj* & *.pk* files are wrong and was wondering why that happens. I need to use these vertical levels for calculations and it is thus essential to have the right ones in the output.

Are the model levels equal to the geometric height if there is no orography?

Thank you!
Best wishes

Change History (3)

comment:1 Changed 5 years ago by jeff

Hi Lina

If you look at your .leave file (xlyyj000.xlyyj.d16013.t102334.leave), search for


                         UM IDEALISED SETTINGS


you can see the vertical grid has been recalculated by the idealised model setting. I don't know much about the idealised model but a bit of looking around it seems the variable grid_number=8 from your idealised model namelist file HS_dlrsi.nml causes the vertical levels to be recalculated in routine idl_ni_init.F90. You need to understand what is happening here and set the correct values for what you want to do.


comment:2 Changed 5 years ago by lboljka

Hi Jeff

Yes the vertical levels are overwritten, and the option that is supposed to allow me to keep the levels from vertical levels namelist file (grid_number = 10) simply crashes with "Newtonian iteration failed to converge". This is for job xlyyk (xlyyk000.xlyyk.d16014.t121606.leave). If you have any ideas please do let me know.

Thank you!

Best wishes

comment:3 Changed 5 years ago by jeff

  • Resolution set to answered
  • Status changed from new to closed

Closing this ticket due to inactivity. Please open a new ticket if you are still experiencing problems with the idealised model.


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