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19991216: model elevation question

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Subject: 19991216: model elevation question
Date: Fri, 17 Dec 1999 14:24:18 -0700
Matt,

the error message implies that the terrain.gsf data file
is not being found. Since you know that the file does exist,
you might need to verify that:
1) Your file permissions allow you to access the file from the 
   path.
2) The line in your script where you define 
   TOPOFL    = /data1/nawips-5.4/terrain/terrain.gsf

   check for any typos in the path or hidden cntrl characters
   (sometimes text editors can stick in a ^H or something if you backspace
   and fudge a character).

3) try running the program interactively instead of from your redirection
   to eliminate the above possibility.

Steve Chiswell
Unidata User Support



>From: "Matthew G. Fearon" <address@hidden>
>Organization: Desert Research Institute
>Keywords: 199912172026.NAA22512

>Steve,
>
>Thank you for this information. It will be very helpful to me.
>I followed all the procedures after retrieving the terrain.tar.Z
>file. I made a direct access binary file from the ascii as well. I
>received the normal completion message after running
>tercnvrt. When I run gdtopo however, I receive the following
>error
>
>$GEMEXE/gdtopo << EOF
> GDFILE    Grid file                         $GEMDATA/HRCBOB.GRD
> GAREA     Grid area                         WV
> GDATTIM   Grid date/time                    LAST
> TOPOFL    Topography file name
> Parameters requested: GDFILE,GAREA,GDATTIM,TOPOFL.
> GEMPAK-GDTOPO> GEMPAK-GDTOPO> GEMPAK-GDTOPO> GEMPAK-GDTOPO> GEMPAK-GDTOPO> [G
> DT
>OPO -12]  Topography file does not exist.
> Parameters requested: GDFILE,GAREA,GDATTIM,TOPOFL.
> GEMPAK-GDTOPO> GEMPAK-GDTOPO>
>
>rm *.nts
>
>Here is my gdtopo program:
>
>$GEMEXE/gdtopo <<EOF
>GDFILE    = us.west
>GAREA     = 25;-125;45;-105
>GDATTIM = 990101/1200
>TOPOFL    = /data1/nawips-5.4/terrain/terrain.gsf
>r
>
>exit
>
>EOF
>
>#$GEMEXE/gpend
>rm *.nts
>
>The terrain.gsf file does exist. Do you know what may be
>the problem ? Please reply at your convienence. Thank you
>again for all your help.
>
>Matt Fearon
>address@hidden
>
>
>
>
>Unidata Support wrote:
>
>> Matt,
>>
>> All models use some smoothed form of surface data since using
>> terrain data at a higher resolution than the grid and/or large
>> discontinuities inadjacent grid point values will cause the model
>> to blow up with anomalous gravity waves and non-hydrostatic
>> forcing.
>>
>> The ETA model employs a step terrain. There are some points about
>> the difference in actiual station elevation and the model elevation in
>> the 32km ETA whitepaper at:
>> http://www.nws.noaa.gov/om/447body.htm
>>
>> You can also look at the FSL RUC 40km topography at:
>> http://maps.fsl.noaa.gov/40kmtopocol.gif
>> They also have ascii 40km and 60km topography datasets for download at:
>> http://maps.fsl.noaa.gov/MAPS.domain.cgi
>>
>> We do have a 5 minute (approx 10km) gridded topography dataset for
>> Gempak which you can use as a gridded data set (eg gdlist, gdpoint etc).
>>
>> To use the gempak terrain dataset, download from the gbuddy ftp account
>> nawips-5.4/contrib/terrain.tar.Z
>>
>> and unpack on your system with:
>>
>> zcat terrain.tar.Z | tar xvf -
>>
>> This will create a directory called terrain which containe
>> the ascii terrain data set (63 Mb) and a program directory called
>> gdtopo which can be used to convert the data into a gempak
>> grid file.
>>
>> First you need to convert the ascii terrain file into a direct access
>> file (like a gempak map datafile). To do this, you need to build the
>> tercnvrt program from the fortran code with:
>>
>> f77 -o tercnvrt tercnvrt.f
>>
>> Then run tercnvrt to create the direct access file, eg:
>>
>> prompt% tercnvrt
>>
>> Please enter name of original terrain dataset: terrain.ascii
>>                                                ^^^^^^^^^^^^^
>>  Now enter name of file which will
>>  contain sector of terrain data: terrain.gsf
>>                                  ^^^^^^^^^^^
>>
>> Now build and install gdtopo by cd'ing into the gdtopo directory
>> and building with:
>>
>> make all
>> make install
>> make clean
>>
>> (This will install the gdtopo program into the $GEMEXE directory and
>> install the ancillary pdf files as well).
>>
>> Now you can create a grid file for some area. Since the maximum number of
>> grid points by default in a gempak grid file is ~97,000 points, this
>> is approximately 311x311 grid points (for the 5 minute data set this is
>> roughly 25 degrees x 25 degrees). In otherwords, even though the database
>> covers the entire globe, you can only view a 25 degree square at a time
>> as a gempak grid file. As an example, I created a file called us.west
>> in the terrain subdirectory that is a 20x20 degree file (garea =
>> 25;-125;45;-105) as an example which you can use.
>>
>> To create your own grid file area, run gdtopo:
>>
>>  GDFILE   = us.west
>>  GAREA    = 25;-125;45;-105
>>  GDATTIM  = 990101/1200
>>  TOPOFL   = terrain.gsf
>>  GEMPAK-GDTOPO>r
>>
>> The gdattim is only used to create a grid time in the output file but
>> really doesn't do anything else.
>>
>> An example of running gdcntr with the us.west grid file that is produced:
>>  GDATTIM  = 990101/1200
>>  GLEVEL   = 0
>>  GVCORD   = pres
>>  GFUNC    = topo
>>  GDFILE   = us.west
>>  CINT     = 200
>>  LINE     = 5/1/1/0
>>  MAP      = 6
>>  TITLE    = 1
>>  DEVICE   = ps
>>  SATFIL   =
>>  RADFIL   =
>>  PROJ     = ced
>>  GAREA    = grid
>>  CLEAR    = y
>>  PANEL    = 0
>>  TEXT     = .5
>>  SCALE    = 0
>>  LATLON   = 7/10/1//1;1
>>  HILO     =
>>  HLSYM    =
>>  CLRBAR   =
>>  CONTUR   = 0
>>  SKIP     = 0
>>  FINT     = 200
>>  FLINE    = 30-7
>>  CTYPE    = c
>>  LUTFIL   =
>>  STNPLT   =
>>  GEMPAK-GDCNTR>r
>> Creating process: ps for queue 251454
>>
>>  Grid file: us.west
>>  GRID IDENTIFIER:
>>     TIME1             TIME2         LEVL1 LEVL2   VCORD PARM
>> 990101/1200                             0          PRES TOPO
>>
>>  GAREA:     grid
>>
>>  MINIMUM AND MAXIMUM VALUES -4765.00  3790.00
>>
>>  LINE CONTOURS:
>>
>>  LEVELS:     -4600.00 -4400.00 -4200.00 -4000.00 -3800.00 -3600.00 -3400.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>>
>>  LEVELS:     -3200.00 -3000.00 -2800.00 -2600.00 -2400.00 -2200.00 -2000.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>>
>>  LEVELS:     -1800.00 -1600.00 -1400.00 -1200.00 -1000.00  -800.00  -600.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>>
>>  LEVELS:      -400.00  -200.00     0.00   200.00   400.00   600.00   800.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>>
>>  LEVELS:      1000.00  1200.00  1400.00  1600.00  1800.00  2000.00  2200.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>>
>>  LEVELS:      2400.00  2600.00  2800.00  3000.00  3200.00  3400.00  3600.00
>>  COLORS:            5        5        5        5        5        5        5
>>  LINTYP:            1        1        1        1        1        1        1
>>  LINWID:            1        1        1        1        1        1        1
>>  LABEL:             0        0        0        0        0        0        0
>> Enter <cr> to accept parameters or type EXIT:
>>
>> I hope this helps you with your work.
>>
>> Steve Chiswell
>> Unidata User Support
>>
>> >From: "Matthew G. Fearon" <address@hidden>
>> >Organization: Desert Research Institute
>> >Keywords: 199912170024.RAA17299
>>
>> >Steve,
>> >
>> >I attached my question below. I just figure I would mention briefly
>> >what I am trying to accomplish first.
>> >
>> >I have created a text file of 40km eta model hght@0%none field or
>> >what is consider the ground surface in the eta model. I have done
>> >this for each grid point for the entire eta grid and each hght has a
>> >corresponding latitude and longitude. I then compared the true
>> >ground surface of certain sounding stations to the heights
>> >from the eta model by locating the closet lat/lon relationship. From
>> >this comparison, I am noticing that the eta heights are always quite
>> >higher than the true ground surface of the sounding sites, except for
>> >FSX which is lower. I attached a list below, the heights are in meters:
>> >
>> >stn       sounding      eta
>> >RNO    1341.5      1776.8
>> >UIL      54.880      229.29
>> >OAK    3.0500      109.45
>> >FSX     2134.1      1740.0
>> >EKO    1551.8       1872.2
>> >BOI      871.95      1371.6
>> >DEN    1612.8       2238.7
>> >TUS     786.59      1084.6
>> >GGW   695.12      832.76
>> >
>> >Do you know if there is a prewritten grid file containing the true
>> >ground
>> >surface elevation (hgt above mean sea level) that I could match to the
>> >lat/lons that are available from the 40km eta ?
>> >
>> >Your suggestions would be greatly appreciated.
>> >Thank you in advance,
>> >
>> >Matt Fearon
>> >address@hidden
>> >
>> >
>>
>> ****************************************************************************
>> 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/     
>> ****************************************************************************
>
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