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Emily, If the NetCDF files have a 2.5x2.5 degree grid spacing that is constant, then that is a CED projection. If you can obtain those files, I have a program called dcreanal that will dump the NetCDF reanalysis grids to gempak files. I included the dcreanal source in the current gempak distribution - you can see in you have the directory $NAWIPS/unidata/ldmbridge/dcreanal in your distribution, or I can pack it up for you. It doesn't get built by default since it requires you to have NetCDF built on your system already. If you have the dcreanal directory, then to build: set the NETCDF and NETCDFINC locations in $NAWIPS/config/Makeinc.common for the location of the NetCDF library and include file on your system, then cd $NAWIPS/unidata/ldmbridge/dcreanal make clean make all make install make clean to run dcreanal: dcreanal netcdf_file gemfile_YYMM.gem The program using YYMM template will create monthly gempak files from the netcdf input file. Let me know if you need the dcreanal sourec (or its available in the gempak patch level 12 distribution we currently provide). Steve Chiswell Unidata User Support >From: Emily K Grover <address@hidden> >Organization: . >Keywords: 199909092030.OAA09294 > >Steve, > >Thanks for the info. Another quick question: I think I can obtain the >files in netCDF format. (They would have a 2.5 by 2.5 grid spacing.) Is is >possible to convert files from netCDF to GEMPAK format? If so, what type >of projecion would I indicate for the 2.5 x 2.5 grid spacing? Thanks again >for your help. > >Emily >_________________________________________________________________________ >Emily K. Grover MMMMMM MMMMMM >University of Michigan MMMMM MMMMM >Atmospheric, Oceanic, and Space Sciences MMMMMM MMMMMM >Mesoscale Meteorology Laboratory MMMMMMM MMMMMMM >734.764.0564 MMMM MMMMM MMMM > MMMM MMM MMMM > MMMM MMMM > MMMMMM MMMMMM >_________________________________________________________________________ > > >On Thu, 9 Sep 1999, Unidata Support wrote: > >> >From: Emily K Grover <address@hidden> >> >Organization: . >> >Keywords: 199909091906.NAA07311 >> >> >To whom it may concern, >> > >> >I am trying to convert reanalysis grib data files into GEMPAK format. I >> >have tried both nagrib and dcgrib. I suspect that my problem lies with the >> >grib file's projection. The reanalysis files have a Gaussian projection. >> >As far as I can tell, GEMPAK doesn't have a Gaussian projection option in >> >its tables. (If I am wrong, please correct me.) Below are the error >> >messages I have received. >> > >> > >> >When I use nagrib I receive the following error message: >> > >> > [NAGRIB -10] Input for GEMPAK output file is blank. >> > >> >When I use dcgrib I get the following error message: >> > >> > Sep 09 18:30:08 dcgrib[6054]: Invalid center id/grid >> > id combination: 721948pres_msl.gem >> > >> > >> >I have already confirmed that I have the proper directory structure and >> >that I have version 5.4 gempak. >> > >> >Any help or suggestions you can offer will be greatly appreciated. Thank >> >you in advance. >> > >> >Emily Grover >> > >> >_________________________________________________________________________ >> >Emily K. Grover MMMMMM MMMMMM >> >University of Michigan MMMMM MMMMM >> >Atmospheric, Oceanic, and Space Sciences MMMMMM MMMMMM >> >Mesoscale Meteorology Laboratory MMMMMMM MMMMMMM >> >734.764.0564 MMMM MMMMM MMMM >> > MMMM MMM MMMM >> > MMMM MMMM >> > MMMMMM MMMMMM >> >_________________________________________________________________________ >> > >> > >> > >> >> >> Emily, >> >> Your assumption is correct. GEMPAK is not capable of handling variable >> spaced grids. The Gaussian grid format varies the grid row spacing >> in the latitudinal direction. All of the Gempak grid functions expect >> a rectangular grid. >> >> In order to convert the data into Gempak format for display, you would need >> to interpolate the data to a regularly spaced grid (eg CED projection). >> >> Steve Chiswell >> **************************************************************************** >> Unidata User Support UCAR Unidata Program >> (303)497-8644 P.O. Box 3000 >> address@hidden Boulder, CO 80307 >> ---------------------------------------------------------------------------- >> Unidata WWW Service http://www.unidata.ucar.edu/ >> **************************************************************************** >> >