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Re: Higher resolution topographic gempak sat files

Alan,

I'll be out of the office next week for the AMS,  but would be happy to
work with you 
more after I return.

It would be possible for me to provide you with the topo to grid to
image programs,
but you would have to run my binaries to do that until your version of
GEMPAK is capable of handling larger grids (since I use the grid
navigation routines to handle the
transformation from lat/lon projection to other projections). So, for a
quick start,
I provided a sample using the 5min dem data since it included bathymetry
as the image you are currently using does.

I created a ~6km resolution GIF as a sample from the 5min dem data at:
http://www.unidata.ucar.edu/staff/chiz/gifs/topo_nam.gif

You can download the gini file that created the image at:
http://www.unidata.ucar.edu/staff/chiz/gifs/ustopo_dem5.gini

For GINI, I used the GOES7 satellite ID here since you probably cannot
remap an unused ID with your version of GEMPAK. The
$GEMTBL/sat/imgtyp.tbl entry to display this image is:
TOPO                 TOPO_DEM5     0     95     33  32768      1
upc_dem5.tbl

You can download the color table for your $GEMTBL/luts directory here:
http://www.unidata.ucar.edu/staff/chiz/gifs/upc_dem5.tbl

The GPMAP parameters to display the image as the GIF above is shown
below, where I've added:
BND = lakes/24 
to fill in the lakes as water color (since the DEM data would be above
sea level and not blue there). You can set the GAREA smaller than dset
as necessary.

 GAREA  = dset
 PROJ       = sat
 SATFIL   = ustopo_dem5.gini
 BND        = lakes/24
 LUTFIL   = default

The 30 second data is great for smaller areas where you can take
advantage of the resolution, more therelater if you feed this is where
you want to go.

Steve Chiswell
Unidata User Support

On Tue, 2007-01-09 at 14:07 -0500, address@hidden wrote:
> Steve,
> 
> It's hard to say just what kind of resolution that we need as I am not
> sure what we are currently using. I think that maybe the one we use is 5
> min. We have had it for at least 5 years.
> 
> I really do not want this to be a lot of work for you. Is there any way
> that we could run the grid-to-image conversion on the data so we could
> play around with various data sets to see what we like? (That assumes it
> would run on our workstations, which run RHEL3 and RHEL4.) It would be
> nice to have some background for general use that is better than what we
> have now but also a much better background if we need to produce much
> higher quality images for publication.
> 
> Alan
> 
> 
> ----- Original Message -----
> From: Steve Chiswell <address@hidden>
> Date: Tuesday, January 9, 2007 12:43 pm
> Subject: Re: Higher resolution topographic gempak sat files
> 
> > Alan,
> > 
> > I have created both 30 second and 5 minute global topography (dem) 
> > datasets.
> > The 5 minute dem data has bathymetry, while the 30 second data set 
> > doesnot.
> > 
> > I provide these as a grid
> > (http://www.unidata.ucar.edu/downloads/gempak/tables/)
> > for use with a program I call GDTOPO which allows users to create a
> > subset for a Gempak grid file. However, it would be possible to map 
> > thegrid into an image to use as a background using the same grid to 
> > imageconversion that I do for our
> > radar composite images.
> > 
> > If you can provide some information regarding the resolution
> > (pixel-->km) you
> > need, I can look into making some background images.
> > 
> > Steve Chiswell
> > Unidata User Support
> > 
> > 
> > 
> > 
> > On Tue, 2007-01-09 at 10:50 -0500, Alan Robson wrote:
> > > Hi Mr Chiswell,
> > > 
> > > My name is Alan Robson and I work in the Development and Training 
> > Branch 
> > > of the Hydrometeorological Precipitation Center in Camp Springs, 
> > > Maryland.   I am not sure if you the right person to address this 
> > > request to and hope you will forward it to the appropriate 
> > individual if 
> > > you are not.
> > > 
> > > We produce many meteorological products for our webpage ( 
> > > http://www.hpc.ncep.noaa.gov/ ) that use a fairly low resolution 
> > > topographic gempak sat file as a background.   This is a sample 
> > of one 
> > > of our most popular products that gets very many webhits:  
> > > http://www.hpc.ncep.noaa.gov/noaa/noaa.gif
> > > 
> > > We are currently attempting to improve the appearance of our 
> > products 
> > > and need to find a higher resolution version of the topographic 
> > gempak 
> > > satellite file to use as a background.
> > > 
> > > Can you help us or give me the name of someone who can?
> > > 
> > > Thanks
> > > 
> > > Alan Robson
> > > HPC/NCEP
> > > Camp Springs, MD
> > > 
> > -- 
> > Steve Chiswell <address@hidden>
> > Unidata
> > 
-- 
Steve Chiswell <address@hidden>
Unidata