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Kevin, The GRIB1 gaussian grids cannot be stored into a GEMPAK grid file because the distance between grid rows is not constant. It would require an interpolation of the points to a regular spaced grid (that hasn't been developed yet). I have been able to use Gaussian and reduced gaussian grids in GRIB2 format since I can store the GRIB2 data in its native format without unpacking (eg the ECMWF TIGGE ensemble on a 800x400 reduced gaussian grid) and display the gaussian rows (though the position is off a little at the poles). Another user a while back found that the same data was available on a 2.5x2.5 degree lat/lon grid which satisfied her needs. Steve Chiswell Unidata User Support > We are unable to decode some grib files from the ERA40 data set. The > problem is an "unknown projection 4": specifically, navigation is unable > to be set since the value of "gds.grid_proj" is 4, while the relevant > function in dcgrib2 only accepts 0, 1,3,5, and 203. Is there any way to > decode these files into GEMPAK grids? > > Thanks, > > Kevin > > ______________________________________________________________________ > Kevin Tyle, Systems Administrator ********************** > Dept. of Earth & Atmospheric Sciences address@hidden > University at Albany, ES-235 518-442-4578 (voice) > 1400 Washington Avenue 518-442-5825 (fax) > Albany, NY 12222 ********************** > ______________________________________________________________________ > > > We are unable to decode some grib files from the ERA40 data set. The > problem is an "unknown projection 4": specifically, navigation is unable > to be set since the value of "gds.grid_proj" is 4, while the relevant > function in dcgrib2 only accepts 0, 1,3,5, and 203. Is there any way to > decode these files into GEMPAK grids? > > Thanks, > > Kevin > > ______________________________________________________________________ > Kevin Tyle, Systems Administrator ********************** > Dept. of Earth & Atmospheric Sciences address@hidden > University at Albany, ES-235 518-442-4578 (voice) > 1400 Washington Avenue 518-442-5825 (fax) > Albany, NY 12222 ********************** > ______________________________________________________________________ > > Ticket Details =================== Ticket ID: ZHX-668060 Department: Support GEMPAK Priority: Normal Status: Closed