UPP - Problem with Maximum 10m wind speed

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oib
Posts: 118
Joined: Mon Jan 31, 2011 3:29 pm

UPP - Problem with Maximum 10m wind speed

Post by oib » Mon Oct 27, 2014 5:24 pm

Hi all,

In WRFV3.6 - ARW I have enabled the output of the registry variable "WSPD10MAX" ("WIND SPD MAX 10 M") and now I see this 2d field into wrfout_ netcdf files produces by wrf.exe.

I have activated "MAX 10m WIND SPEED" in wrf_cntrl.parm and run unipost.exe with the entry:

Code: Select all

 (MAX 10m WIND SPEED  ) SCAL=( 4.0)
 L=(10000 00000 00000 00000 00000 00000 00000 00000 00000 00000 00000 00000 00000 00000)
The problem is that I do not see the corresponding field in the grib file produced by unipost.

In the unipost.exe log I can see that it does the processing of that field:

Code: Select all

SRD ***** outputting WSPD10MAX 
 GRID NUMBER =          255
 IOFORM in GRIBIT =netcdf              
 IGDS in GRIBIT=            0         255           3         226         208
       39651        7051         136       12300        4000        4000
           0          64           0       43500       43500           0
           0
GRIBIT:  229 MAX 10m WIND SPEED   105     0    10
Any suggestion to fix that :?:

meteoadriatic
Posts: 1588
Joined: Wed Aug 19, 2009 10:05 am

Re: UPP - Problem with Maximum 10m wind speed

Post by meteoadriatic » Mon Oct 27, 2014 6:14 pm

Only in grads ctl file is missing, or it is missing if you look using wgrib?

oib
Posts: 118
Joined: Mon Jan 31, 2011 3:29 pm

Re: UPP - Problem with Maximum 10m wind speed

Post by oib » Tue Oct 28, 2014 7:50 am

It is missing in the wgrib output

oib
Posts: 118
Joined: Mon Jan 31, 2011 3:29 pm

Re: UPP - Problem with Maximum 10m wind speed

Post by oib » Thu Oct 30, 2014 8:57 am

After investigating I found that the max wind speed at 10 m above ground is in the grib!
The problem is that max wind speed 10 m is badly recognized as SNOHF10m ;)
That's the wrong entry in .ctl file:

Code: Select all

SNOHF10m  0 229,105,10 ** 10 m above ground Snow phase-change heat flux [W/m^2]
It seems like a unipost and/or a wgrib misunderstanding caused by the value '229' of the GRIB 1 PARAMETER (TABLE 2) assigned by unipost for both variables.

But note that the value '105' assigned to the GRIB 1 INDICATOR OF TYPE OF LEVEL (TABLE 3) reveals that the variable is really the Max Wind Speed at 10 m.

In fact the right value for 'Snow phase-change heat flux' should be '1' (that indicates that the level is 'the ground'), not '105'.

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