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20020814: canadian gem and nexrad

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  • Subject: 20020814: canadian gem and nexrad
  • Date: Wed, 14 Aug 2002 15:09:58 -0600
>From: Mike Trexler <address@hidden>
>Organization: NCSU
>Keywords: 200208141743.g7EHhEK21033 IDD

Mike,

>I have two questions for you....
>
>1.  I requested access to the canadian gem a couple weeks ago
>and have since been in touch with Dov who has allowed my feed.
>My question is what should my request line look like in my
>ldmd.conf?

Here is what we are using to ingest GEM data from CMC on a machine
here at the UPC:

#
# GEM data: (aka dns2.cmc.ec.gc.ca)
#
request CMC "CMC_GEM_reg_.*" ftp.cmc.ec.gc.ca

You may want to change this for your own use.

>All Dov has provided me is his machine name? What is the product stream name?

All LDM feed types are listed in:

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

From this page, you can see that equivalent feed types for GEM data
are:  GEM, CMC, FT20.

>and then do I just specify ".*"?

What you want to ingest from any IDD stream is ultimately up to you.
I would start using the ".*" pattern and then look through what you
get and decide if you want to request less.

>2.  I'm confused about the nexrad level III products.  Maybe I'm
>stupid, because I did read the webpage about this, but still have
>questions.  Here's what I want to do...simply get the 1 km
>mosaic that Chiz creates and injects in the idd.

The 1 km composite of base reflectivities at tilt 1 are included in
the FNEXRAD feed.  They are sent with headers that look like:

rad/NEXRCOMP/1km/n0r_20020814_2005

>This is in Gini format, right?

Yes.

>Can you tell me exactly what I need to specify
>to start bringing this in?

A request line that looks like the following will work:

request FNEXRAD "^rad/NEXRCOMP/1km" <the upstream host you want to feed from>

You need to:

o replace the last bit above with the machine you are requesting the feed from

o add an action to your LDM's pqact.conf file to do something with the
  products when they are received.

>thanks for everything,

You are welcome.

Tom Yoksas