Search found 18 matches

by wallis
Wed Dec 16, 2020 9:42 pm
Forum: WRF Physics
Topic: 3D radiation
Replies: 3
Views: 97

Re: 3D radiation

GHI, ideally DHI/DNI as well.
by wallis
Tue Dec 15, 2020 10:29 pm
Forum: WRF Physics
Topic: 3D radiation
Replies: 3
Views: 97

3D radiation

Are there any radiation modules that output 3D radiation, to be used to calculate solar irradiance at altitude?
The goal is to calculate solar power for an aircraft in flight.
by wallis
Thu Nov 19, 2020 4:40 am
Forum: WRF Physics
Topic: Poor results with NoahMP versus Noah
Replies: 6
Views: 305

Re: Poor results with NoahMP versus Noah

I analysed both domains against observations from GDAS, comparing the average/median/stddev error. But I can also just load up all kinds of subsequent parameters and see subsequent catastrophically wrong results, like PBLH being nearly zero across large areas at the height of summer. Surface soil mo...
by wallis
Sun Oct 25, 2020 11:28 am
Forum: WRF Physics
Topic: Poor results with NoahMP versus Noah
Replies: 6
Views: 305

Re: Poor results with NoahMP versus Noah

Hi Ming, Thanks for getting back to me. 1) Cumulus is disabled already 2) Confirmed disabled slope_rad, mosaic_lu, sf_surface_mosaic and adaptive timestep 3) I am using 24, which I understand is "fast" RRTMG - I have changed to 4, plain RRTMG. Unfortunately the results were slightly better but still...
by wallis
Fri Oct 16, 2020 11:28 am
Forum: WRF Physics
Topic: Poor results with NoahMP versus Noah
Replies: 6
Views: 305

Re: Poor results with NoahMP versus Noah

Hi,
See linked the namelist.input:
https://pastebin.com/ZP8BzpF0
by wallis
Tue Oct 13, 2020 10:19 pm
Forum: WRF Physics
Topic: Poor results with NoahMP versus Noah
Replies: 6
Views: 305

Poor results with NoahMP versus Noah

Hi, I currently use Noah and have a small (-1c) cold bias - I read on this forum that NoahMP can improve this situation. Unfortunately just from toggling Noah to NoahMP I get catastrophically wrong results, -3c cold bias and +5c dewpoint bias. This was surprising as I understood they should behave s...
by wallis
Tue Sep 22, 2020 10:41 am
Forum: Special Running Options
Topic: Obs Nudging with DFI
Replies: 5
Views: 437

Re: Obs Nudging with DFI

Hi,
Is this bad interaction documented anywhere?
I'm doing short range (0-24 hour) forecasts from GFS output +0, but by the time that is available there is already 4 hours of observations available, so I nudge the model with those observations.
by wallis
Thu Sep 17, 2020 3:08 pm
Forum: Special Running Options
Topic: Obs Nudging with DFI
Replies: 5
Views: 437

Re: Obs Nudging with DFI

Hi, So I've debugged this further and determined it's related to dfi. With dfi_opt = 3 It crashes with File open on obs nudging unit ( 61 ) with wrong name File open on obs nudging unit is named /home/wrf/OBS_DOMAIN101 but it should be named OBS_DOMAIN101 This likely means this unit number was opene...
by wallis
Sun Sep 06, 2020 2:18 pm
Forum: Special Running Options
Topic: Observation nudging in a nest
Replies: 7
Views: 511

Re: Observation nudging in a nest

I have made some progress - setting max_obs to extreme values seems to avoid the crash, >1000000 is needed even though I only have a few hundred observations. Is max_obs possibly meant to be set to num_observations * MPI processes * tiles? I am running with >60 MPI processes and >30 tiles. Unfortuna...
by wallis
Wed Sep 02, 2020 2:54 pm
Forum: Special Running Options
Topic: Observation nudging in a nest
Replies: 7
Views: 511

Re: Observation nudging in a nest

Hi, Thanks for looking into this. I am only trying to do obs nudging (obs_nudge_opt), not grid nudging currently, so I think wrffdda isn't being used(?). As for this issue though, see attached as requested. Version is WRF 4.2.1 The linked post is a different problem - I have subsequently discovered ...
by wallis
Sat Aug 29, 2020 10:40 am
Forum: Special Running Options
Topic: Observation nudging in a nest
Replies: 7
Views: 511

Re: Observation nudging in a nest

To make this weirder, if it's compiled with dm+sm, it works, if it's compiled with dm alone, it doesn't.
Something is definitely wrong in the tiling in ftdda.
by wallis
Sat Aug 29, 2020 7:23 am
Forum: Special Running Options
Topic: Observation nudging in a nest
Replies: 7
Views: 511

Re: Observation nudging in a nest

Interestingly, if I set numtiles = 1, I am able to run with multiple MPI processes. Any values higher than 1 and it crashes.
So I'm suspicious there is a problem with the tiling/MPI code which seems eerily similar to viewtopic.php?f=45&t=5391
by wallis
Fri Aug 28, 2020 8:08 pm
Forum: Special Running Options
Topic: Observation nudging in a nest
Replies: 7
Views: 511

Observation nudging in a nest

I am setting up observation nudging in my nested domains. Currently I am generating little_r files and everything works well as long as I don't activate obs nudging on the nest with multiple MPI processes. If I run with >2 MPI process, and have a OBS_DOMAIN201 file present, the model crashes during ...
by wallis
Fri Aug 28, 2020 1:01 pm
Forum: Special Running Options
Topic: observation nudging with dropsonde data
Replies: 5
Views: 479

Re: observation nudging with dropsonde data

Hi Zheng, did you find a solution to this? I have crashes with >1 MPI processes, but the run completes successfully with only one process.
This behaviour is only present with obs nudging a nest.
by wallis
Thu Aug 27, 2020 8:59 pm
Forum: Special Running Options
Topic: Obs Nudging with DFI
Replies: 5
Views: 437

Obs Nudging with DFI

Hi, I'm trying to setup obs nudging for my WRF runs, with a nest, but I'm hitting this error. Does anyone know how to proceed? OBSERVATION NUDGING IS ACTIVATED FOR MESH 2 WRF scheme selected for horizontal spreading of surface obs Regime-based VIF scheme selected for vertical spreading of surface ob...
by wallis
Mon May 18, 2020 7:16 pm
Forum: Operational Implementation
Topic: Operational WRFDA setup
Replies: 0
Views: 324

Operational WRFDA setup

Hi, I'm trying to setup some operational forecasts using WRF. Currently I have WRF working by itself initializing from GFS 0.25 data. But instead I would like to know if it is better practice or likely to give better results to initialize WRF via WRFDA 4DVar, also using GFS 0.25 data. Is anyone able...
by wallis
Sun Nov 03, 2019 10:11 pm
Forum: WRF Physics
Topic: Condensation Heating
Replies: 3
Views: 368

Re: Condensation Heating

Thanks for that, can you elaborate a little more? I don't understand the units associated with these parameters, is this a rate of change?
by wallis
Wed Oct 23, 2019 6:36 pm
Forum: WRF Physics
Topic: Condensation Heating
Replies: 3
Views: 368

Condensation Heating

Are there any microphysics/PBL modules that calculate or output the effects of condensation heating from shallow cumulus, either in terms of heat/energy or convective velocity (w*)?
Failing that, does anyone have any pointers as to how to calculate that from the output variables available?

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