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Re: 19990127: grib to netcdf

On Mon, 8 Feb 1999, Melissa Richey wrote:

> Hi Robb-
> Thanks-
> 
> The official (?) Ruc-2 grib table can be found at
> 
> http://maps.fsl.noaa.gov/ruc2gribtable.html .
> 
> It states that NCEP needs to permanently assign that number, but
> we have been able to access water vapor mixing ratio, using
> the code number 185, in another program which degribs into
> a format different from netcdf.

Missy,

Here's the scoop, the parms from 0-127 are standard. From 128-255 it's up
to the centers to define the parms.  For the ruc2 comming from NOAAport or
NMC the center is 7 (NWS) and then parm 185 is "Turbulence SIGMET/AIRMET".
If the ruc2 comes directly from FSL then the center is 59 and parm 185 is
"water vapor mixing ratio".  The ruc2 data the Gempak decodes the same
manner as gribtonc because the center is 7.  I can't change gribtonc
because it would be wrong.  I suspect that the degribber from FSL either
changed the parm 185 or the center. I checked the gribtonc code and there
is no logic in it to make it center dependant.  Presently it's low
priority because it would take almost a week time.. I know this doesn't
help your situation at all.  If you have any ideas I would like to hear
them. I guess you could kulge your own gribtonc to perform according to
center FSL. At this point I want to wait to see what comes out in the new 
388 Grib manual. I don't have a time frame for the next release.


Robb... 



> 
> Missy
> 
> + 
> + Just wanted to let you know that I'm looking at the problem. It's appears
> + to be a  gribtonc coding problem, but I'm looking at ruc2.cdl
> + modification solution.
> + 
> + 
> + On Fri, 5 Feb 1999, Melissa Richey wrote:
> + 
> + > Hi Robb- 
> + > Thanks for your help with the gribtonc command line. 
> + > I was able to figure out what was wrong from the output and I
> + > have been getting pretty good results. I have however, another question 
> + > (or two) for
> + > you. We would like to degrib the variable "water vapor mixing ratio".
> + > In the ruc2.cdl file there is only a variable for "cloud water
> + > mixing ratio". In the official grib table, the grib code associated to
> + > "water vapor mixing ratio" is 185,
> + 
> + Where's the official grib table?  Wonder why it would be different then
> + the 388 Grib manual?
> + 
> + Robb...
> + 
> +  but in the grib document you 
> + > refer to in another one of your emails, it shows that associated
> + > to code 185 is "Turbulence SIGMET/AIRMET", which is the reserved_hybr
> + > variable in the ruc2.cdl file. All the other variables that I need
> + > degrib successfully, but when the decoder gets to the reserved_hybr 
> + > variable, in the log file it prints out 28 levels of
> + > 
> + > Feb 04 22:30:52 gribtonc[988]: oversize GRIB product
> + > 
> + > and then at the 29th level, it prints out the typical decoding
> + > output
> + > 
> + > Feb 04 22:30:52 gribtonc[988]: 149: wrote reserved_hybr(0,28,*,*) to 
> ruc2.nc
> + > 
> + > for the rest of the 40 levels.
> + > 
> + > Why is this happening, and is there a variable for "water vapor mixing
> + > ratio"? I looked in param.c, but couldn't find anything like that.
> + > I am using a hybrid-coodinate ruc2 grib file.
> + > 
> + > Thanks!!!
> + > 
> + > Missy
> + > 
> + > 
> + 
> ===============================================================================
> + Robb Kambic                            Unidata Program Center
> + Software Engineer III                          Univ. Corp for Atmospheric 
> Research
> + address@hidden                 WWW: http://www.unidata.ucar.edu/
> + 
> ===============================================================================
> + 
> + 
> 

===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================