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20010222: hagl vs hght in gempak decoders

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  • Subject: 20010222: hagl vs hght in gempak decoders
  • Date: Thu, 22 Feb 2001 09:33:20 -0700
Bill,

The grib products just contain numbers for coordinates, parameters, etc.
The tables in $GEMTBL/grid relate the number to a string used in decoding.

Vertical cordinates are given in $GEMTBL/grid/vcrdgrib1.tbl.
Grib coordinate 105 for example is height above ground. The GNAM
column is the string that will appear in the decoded gempak file.

Steve Chiswell
Unidata User Support



>From: address@hidden (William Gallus)
>Organization: UCAR/Unidata
>Keywords: 200102221624.f1MGOnL19320

>Hello,
>
>Years ago, our gempak feed gave us 2-m Temp and dew point with GVC=HGHT.
>Then, upon upgrading, GVCORD changed to HAGL.  It remained that way for
>years, but upon upgrading again this week, these parameters now require
>GVC=HGHT again.
>
>Do we have the ability to control whether this vertical coordinate is
>called HGHT, or HAGL?  These changes are real headaches for us because
>we will have to change many scripts.  In addition, I've archived many
>cases over the years, which I use in my classes.  Students often use
>garp to access the data, and it becomes quite messy having to tell them
>that for cases from May 1997-Jan 2001, they need to select SFCT(F) from
>one menu (like General), but for other dates, select SFCT(F) from
>the archive menu  (where the SFCT(F) function uses GVCORD=HAGL in one
>and HGHT in another).
>
>I would guess our omega parameter may have changed too (used to be OMEG,
>then was OMEGA).
>
>Bill
>**********************************************
>*  Bill Gallus                               *
>*  Asst. Prof. of Meteorology                *
>*  Dept. of Geological and Atmospheric Sci.  *
>*  3025 Agronomy Hall                        *
>*  Iowa State University                     *
>*  Ames, IA 50011                            *
>*  (phone) 515-294-2270                      *
>*  (fax)   515-294-2619                      *
>**********************************************
>