Re: tips to unstagger data from WRF

On example 7, they write about a "mass grid." there are so many terms
for "grids" these days (i.e. "A", "B", "C"). What is a Mass Grid?
-Erik

On Dec 11, 2007 2:15 PM, Dennis Shea <shea_at_ucar.edu> wrote:
> I suggest the WRF functions already mentioned
> http://www.ncl.ucar.edu/Document/Functions/wrf.shtml
> ===
> These are as much WRF questions as NCL
> http://www.mmm.ucar.edu/wrf/users/graphics/NCL/NCL.htm
>
> You can send WRF questions to wrfhelp_at_ucar.edu
> ===
> However, given the high resolution of the WRF grids,
> the array syntax in Example 7 at
> http://www.ncl.ucar.edu/Applications/wrflc.shtml
> should yield adequate values for most applications.
>
>
> Erik Noble wrote:
> > Hi.
> > The post processor does not install on the APPLE or the SGI machine we
> > are using.
> > Unfortunately, the post processor step is not an option for me.
> >
> > Gary or anyone else, do you still have advice about destaggerring
> > after converting to pressure levels.
> > the converting to pressure command can be found here:
> > http://www.mmm.ucar.edu/wrf/users/graphics/NCL/Examples/PressureLevel1/wrf_PressureLevel1.ncl
> >
> > Where an example of the interpret to pressure command is: IT HAS TO
> > BE PERFORMED IN A DO LOOP FOR TIME (bummer!!!)
> >
> > variable = wrf_user_getvar(a,"variable",it) ; variable of interest
> > p = wrf_user_getvar(a, "pressure",it) ; pressure is our vertical coordinate
> >
> > do it = 0,ntimes-1 ; TIME LOOP
> > do level = 0,nlevels-1 ; LOOP OVER LEVELS
> > pressure = 700 ; Sample Pressure level
> > Variable_Plane = wrf_user_intrp3d(variable,p,"h",pressure,0.,False)
> > end do ; END OF LEVEL LOOP
> > end do ; END OF TIME LOOP
> >
> >
> > After this what is the step for unstaggering? The WRF-Help team does
> > not provide anymore assistance beyond this step.
> > -Erik
> >
> >
> > On Dec 11, 2007 8:08 AM, Jan Ploski <Jan.Ploski_at_offis.de> wrote:
> >
> >> Gerry Creager <gerry.creager_at_tamu.edu> schrieb am 12/11/2007 02:03:49 PM:
> >>
> >>
> >>
> >>> Jan Ploski wrote:
> >>>
> >>>> ncl-talk-bounces_at_ucar.edu schrieb am 12/11/2007 12:46:43 AM:
> >>>>
> >>>>
> >>>>> I am trying to look at 700 mb winds. Correct me if I am wrong but to
> >>>>>
> >> do
> >>
> >>>> this
> >>>>
> >>>>> brings in an extra step of interpolating to pressure level using
> >>>>>
> >> WRF-NCL
> >>
> >>>>> code.
> >>>>> So first I have to interpolate the data usingthe wrf_interp-3d
> >>>>>
> >> function
> >>
> >>>> and
> >>>>
> >>>>> then use the " wrf_uvmet" function?
> >>>>>
> >>>> Hello,
> >>>>
> >>>> This task is certainly doable with NCL alone. However, we solved it
> >>>>
> >> (for
> >>
> >>>> computing wind velocity at a given relative height above the terrain
> >>>> surface) in two steps:
> >>>>
> >>>> 1. Run NCEP WRF Postprocessor on the WRF output to destagger and
> >>>>
> >> extract
> >>
> >>>> U, V WIND ON MDL SFCS, HEIGHT ON MDL SFCS, SURFACE HEIGHT.
> >>>> 2. Read in the resulting GRIB file with NCL and interpolate to a
> >>>>
> >> desired
> >>
> >>>> height using wrf_interp_3d_z.
> >>>>
> >>>> I think you could do much the same for "ON PRESS SFCS".
> >>>>
> >>> Does this work for ARW as well as NMM? I was under the impression the
> >>> Postprocessor was only for NMM code.
> >>>
> >> The NMM postprocessor and the described method both work for ARW (this is
> >> what we are using).
> >>
> >> The documentation is at
> >> http://www.dtcenter.org/wrf-nmm/users/docs/user_guide/WPS/users_guide_nmm_chap7_v1_WPS.htm
> >>
> >> Best regards,
> >> Jan Ploski
> >>
> >> --
> >> Dipl.-Inform. (FH) Jan Ploski
> >> OFFIS
> >> Betriebliches Informationsmanagement
> >> Escherweg 2 - 26121 Oldenburg - Germany
> >> Fon: +49 441 9722 - 184 Fax: +49 441 9722 - 202
> >> E-Mail: Jan.Ploski@offis.de - URL: http://www.offis.de
> >>
> >>
> >>
> > _______________________________________________
> > ncl-talk mailing list
> > ncl-talk_at_ucar.edu
> > http://mailman.ucar.edu/mailman/listinfo/ncl-talk
> >
>
>
> --
> ======================================================
> Dennis J. Shea tel: 303-497-1361 |
> P.O. Box 3000 fax: 303-497-1333 |
> Climate Analysis Section |
> Climate & Global Dynamics Div. |
> National Center for Atmospheric Research |
> Boulder, CO 80307 |
> USA email: shea 'at' ucar.edu |
> ======================================================
>
>
>
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Received on Wed Dec 12 2007 - 09:10:38 MST