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20020604: accessing Unidata NEXRAD 1 km National mosaic products

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  • Subject: 20020604: accessing Unidata NEXRAD 1 km National mosaic products
  • Date: Tue, 04 Jun 2002 17:52:01 -0600
>From: Sidney Gauthreaux <address@hidden>
>Organization: Clemson University
>Keywords: 200206042029.g54KTYJ26937 IDD FNEXRAD

Sidney,

>Yesterday I was talking  with Linda Miller and she mentioned the 
>availability of 1 km resolution national mosaics.  How do I acquire such 
>imagery?  Your attention to this matter is greatly appreciated.

There are basically two ways that you can access the imagery:

1) setup an LDM at your site and be fed the images via our IDD
2) view the images from one of several cooperating community data
   servers using a McIDAS ADDE-enabled application (e.g., McIDAS or
   MetApps IDV)

The LDM software and participation in our IDD (Internet Data Distribution)
are free as are the ADDE-enabled applications, so cost is not an issue.

To learn more about the various options, please visit the following
web pages:

LDM:
http://www.unidata.ucar.edu/packages/ldm/index.html

IDD:
http://www.unidata.ucar.edu/projects/idd/index.html

McIDAS:
http://www.unidata.ucar.edu/packages/mcidas/index.html

MetApps:
http://www.unidata.ucar.edu/projects/metapps/index.html

The process to get the data by the LDM (IDD) is basically:

1) download and install the LDM at your site (binary versions of the LDM
   are available for a wide variety of popular Unix platvorms); the
   LDM only runs on Unix...

2) get assigned an upstream feed site by us

3) configure your LDM to request the composites in the IDD from the
   upstream feed site we assign you

4) decode the data files if desired; they are broadcast in a PNG-compressed
   format (a standard GINI image header followed by the image data 
   that has been PNG compressed).  Our ldm-mcidas package can be downloaded
   (binaries are available like for the LDM) that will decode the compressed
   images into standard GINI format (GINI, if your are not aware, is the
   format of the images sent in NOAAPORT)

5) setup data scouring for the images; the uncompressed 1 km images are
   each 14 MB in size, so data scouring is important

I hope that this helped.  Please let us know which routine you want to
pursue.  We can help you in the installation process for either of the
options that you decide to pursue.

>Sidney A. Gauthreaux, Jr.
>Department of Biological Sciences
>Clemson University
>Clemson, SC 29634-0326
>864 656-3584 (office)
>864 656-0435 (fax)

Tom Yoksas