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>From: =?ISO-8859-1?Q?Christian_Pag=E9?= <address@hidden> >Organization: UCAR/Unidata >Keywords: 200211141854.gAEIsmL02234 >Hi, > >Thank you, it works very well with gddiag. By the way, specifing >guess=file*f012 also works. >Is there a way to detect a missing model field, since if the model >field is not available I don't want to use the first guess since in >that case it would stop the oabsfc program with an error. > >Thanks, The easiest way to detect a missing PMSL model field would be to use the gdinfo program, with GLEVEL=0, GVCORD=none, GFUNC=PMSL, GDATTIM=f012, and OUTPUT=f/filnam. If the grid does not exist, then the output in filnam will have a message similar to: [GDU 2] Did not find any matching grids Then you could have you script chose the correct setting for GUESS. Steve Chiswell > > >On Jeudi, nove 14, 2002, at 12:27 America/Montreal, Unidata Support >wrote: > >> >> Christian, >> >> To use a first guess field, the parameter name must exist in >> the grid file as it is being gridded in the surface file. >> Since you are gridding PANY from the surface file, you need a >> pressure grid of "PANY" in your grid file. You can use the gddiag >> program to rename the grid with GFUNC=PMSL and GRDNAM=PANY. >> >> You may also need to specify the gdattim fully in the GUESS parameter, >> eg GUESS=file*021114/0000f000 >> >> Steve Chiswell >> >> >> >>> From: =?ISO-8859-1?Q?Christian_Pag=E9?= <address@hidden> >>> Organization: UCAR/Unidata >>> Keywords: 200211141400.gAEE03L22185 >> >>> Hi, >>> >>> I am trying to do a Barnes surface analysis using sfparm=pany but with >>> a first guess file using model data. >>> The problem is that it seems that for first guess, using sfparm=pany >>> doesn't work. I must use pany because in Europe altm is used to report >>> mean sea-level pressure (except pmsl for buoys and boats). In oabsfc, >>> using sfparm=pmsl doesn't work because oabsfc doesn't find enough data >>> in the surface file (but first guess data is found), while using >>> sfparm=altm (or pany) is not working because oabsfc doesn't find the >>> first guess data... Here is the output: >>> >>> (avn.grid has been create with oagrid the same way europe_surf.grid >>> file was created) >>> >>> 246 [/io/httpd/gempak/ff] % gdbiint >>> GDFILE Grid file 2002111400_avn201.gem >>> GDOUTF Output grid file avn.grid >>> GFUNC Scalar grid pmsl >>> GLEVEL Grid level 0 >>> GVCORD Grid vertical coordinate none >>> GDATTIM Grid date/time all >> GDNUM Grid numbers >>> Parameters requested: >>> GDFILE,GDOUTF,GFUNC,GLEVEL,GVCORD,GDATTIM,GDNUM. >>> GEMPAK-GDBIINT>gdattim=f012 >>> GEMPAK-GDBIINT>r >>> Building interpolation array for 103 columns 72 rows >>> Input grid file contains 451 grids >>> Interpolating PMSL 021114/0000F012 0 -1 >>> NONE >>> Parameters requested: >>> GDFILE,GDOUTF,GFUNC,GLEVEL,GVCORD,GDATTIM,GDNUM. >>> GEMPAK-GDBIINT>e >>> >>> >>> WITH SFPARM=pany >>> --------------------------- >>> 248 [/io/httpd/gempak/ff] % oabsfc >>> SFFILE Surface data file >>> /io/ldm/data/gempak/surface/sao/20021114_sao.gem >>> GDFILE Grid file 2002111400_avn201.gem >>> SFPARM Surface parameter list pany >>> DATTIM Date/time 13 >>> DTAAREA Data area for OA 16;-30;72;50 >>> GUESS Guess file*time europe_surf.grid >>> GAMMA Convergence parameter 0.3 >>> SEARCH Search radius/Extrapolation 20 >>> NPASS Number of passes 2 >>> QCNTL Quality control threshold >>> Parameters requested: >>> SFFILE,GDFILE,SFPARM,DATTIM,DTAAREA,GUESS,GAMMA, >>> SEARCH,NPASS,QCNTL. >>> GEMPAK-OABSFC>gdfile=europe_surf.grid >>> GEMPAK-OABSFC>dattim=12 >>> GEMPAK-OABSFC>dattim=13 >>> GEMPAK-OABSFC>guess=avn.grid*f012 >>> GEMPAK-OABSFC>r >>> [OABSFC 6] WARNING: Area is not DATA area in file. >>> 2 duplicate stations eliminated. >>> >>> OABSFC PARAMETERS: >>> >>> Output grid file: europe_surf.grid >>> Number of x, y points: 103 72 >>> Grid bnds: 16.00 -30.00 71.38 49.56 Grid xtnd: 2 2 >>> 2 2 >>> Station spacing: 1.57 >>> Guess grid file: avn.grid >>> Guess time: f012 >>> Surface file: >>> /io/ldm/data/gempak/surface/sao/20021114_sao.gem >>> Data area: 16;-30;72;50 >>> Parameters: PANY >>> QC threshold: 0.0 >>> Time: 021114/1300 >>> GAMMA: 0.30 SEARCH: 20.00 NPASS: 2 >>> No data extrapolation will occur. >>> Enter <cr> to accept parameters or type EXIT: >>> >>> Processing data at time 021114/1300 >>> [DG -7] Input grid ... cannot be found. >>> [OA -5] Guess grid could not be found. >>> Parameters requested: >>> SFFILE,GDFILE,SFPARM,DATTIM,DTAAREA,GUESS,GAMMA, >>> SEARCH,NPASS,QCNTL. >>> >>> WITH SFPARM=pmsl >>> --------------------------- >>> 253 [/io/httpd/gempak/ff] % oabsfc >>> SFFILE Surface data file >>> /io/ldm/data/gempak/surface/sao/20021114_sao.gem >>> GDFILE Grid file europe_surf.grid >>> SFPARM Surface parameter list pany >>> DATTIM Date/time 13 >>> DTAAREA Data area for OA 16;-30;72;50 >>> GUESS Guess file*time avn.grid*f012 >>> GAMMA Convergence parameter 0.3 >>> SEARCH Search radius/Extrapolation 20 >>> NPASS Number of passes 2 >>> QCNTL Quality control threshold >>> Parameters requested: >>> SFFILE,GDFILE,SFPARM,DATTIM,DTAAREA,GUESS,GAMMA, >>> SEARCH,NPASS,QCNTL. >>> GEMPAK-OABSFC>sfparm=pmsl >>> GEMPAK-OABSFC>r >>> [OABSFC 6] WARNING: Area is not DATA area in file. >>> [OABSFC -7] There are too few stations in data subset area. >>> [OABSFC 9] No data from >>> /io/ldm/data/gempak/surface/sao/20021114_sao.gem will be used. >>> [OABSFC -9] No valid parameters have been entered. >>> Parameters requested: >>> SFFILE,GDFILE,SFPARM,DATTIM,DTAAREA,GUESS,GAMMA, >>> SEARCH,NPASS,QCNTL. >>> >>> WITH SFPARM=altm >>> --------------------------- >>> GEMPAK-OABSFC>sfparm=altm >>> GEMPAK-OABSFC>r >>> [OABSFC 6] WARNING: Area is not DATA area in file. >>> 2 duplicate stations eliminated. >>> >>> OABSFC PARAMETERS: >>> >>> Output grid file: europe_surf.grid >>> Number of x, y points: 103 72 >>> Grid bnds: 16.00 -30.00 71.38 49.56 Grid xtnd: 2 2 >>> 2 2 >>> Station spacing: 1.57 >>> Guess grid file: avn.grid >>> Guess time: f012 >>> Surface file: >>> /io/ldm/data/gempak/surface/sao/20021114_sao.gem >>> Data area: 16;-30;72;50 >>> Parameters: ALTM >>> QC threshold: 0.0 >>> Time: 021114/1300 >>> GAMMA: 0.30 SEARCH: 20.00 NPASS: 2 >>> No data extrapolation will occur. >>> Enter <cr> to accept parameters or type EXIT: >>> >>> Processing data at time 021114/1300 >>> [DG -7] Input grid ... cannot be found. >>> [OA -5] Guess grid could not be found. >>> Parameters requested: >>> SFFILE,GDFILE,SFPARM,DATTIM,DTAAREA,GUESS,GAMMA, >>> SEARCH,NPASS,QCNTL. >>> >>> >>> Is there something I am missing to make it work? >>> >>> Thanks again, >>> >>> Christian Pagé >>> address@hidden >>> http://meteocentre.com/ http://meteoalerte.com/ >>> >>> Etudiant au Doctorat en Sciences de l'environnement UQAM >>> +1 514 987 3000 ext. 2376 >>> >> >> *********************************************************************** >> Unidata User Support UCAR Unidata >> (303)497-8643 P.O. >> address@hidden Boulder, CO >> ----------------------------------------------------------------------- >> Unidata WWW Service >> *********************************************************************** >> > >Christian Pagé >address@hidden >http://meteocentre.com/ http://meteoalerte.com/ > >Etudiant au Doctorat en Sciences de l'environnement UQAM >+1 514 987 3000 ext. 2376 >