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20050926:CMC GEM change for LDM/IDD

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  • Subject: 20050926:CMC GEM change for LDM/IDD
  • Date: Mon, 26 Sep 2005 13:45:51 -0600 (MDT)
Bonjour Yves,

I posted your suggested announcement last week:

(more text after announcement)

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Date: Thu, 22 Sep 2005 14:39:22 -0600 (MDT)
From: Jeff Weber <address@hidden>
To: address@hidden
Subject: 20050922:Changes in IDD GEM/CMC distribution

Dear users of CMC GEM model data,

As of the 12Z production run on October 18th, 2005, the GEM model dataset
made available via LDM/IDD will be enlarged and enhanced, as described
below:

*Content changes

The main change in contents consists in the addition of several new
vertical levels for the basic meteorological fields of geopotential
height, moisture, temperature, and wind.  These will be augmented to 28
pressure levels. Detailed information on available fields is available
at the following URL :

http://weatheroffice.ec.gc.ca/grib/Low-resolution_grib_e.html

The grid resolution and coverage are almost identical to our current LDM
grid ; the only difference is one additional row of grid points along
the northern edge of the grid.  The grid dimensions will then be 135x95
instead of 135x94.  New grid specifications can be found at

http://weatheroffice.ec.gc.ca/grib/CMC_GRIB_Technical_Grid_Specifications_e.html#low_res_reg

*New naming convention

In order to accomodate the changes in contents, we need to modify the
file naming convention for the LDM GRIB files.  Details of the new
file-naming convention can be found at :

http://weatheroffice.ec.gc.ca/grib/Low-resolution_grib_e.html#convention

The dataset will be made identical with the GRIB dataset available via
http at :

http://dd.weatheroffice.ec.gc.ca/public/grib/lores/CMC_reg_00

and

http://dd.weatheroffice.ec.gc.ca/public/grib/lores/CMC_reg_12

For additional information, please contact:

Yves Pelletier
address@hidden , (514) 421-4662
Acting Chief, Implementation and Operational Services Division
Operations Branch


-----

We greatly appreciate your efforts to make this data available, and to
document the changes in the feed. Since the post we have not heard any
negative comments from the ~20 ingesters of the CMC GEM data feed. We feel
we have given plenty of lead time for this transition, so recommend we
proceed as planned for the switch on October 18th..

Thanks again,

Jeff
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Jeff Weber                                    address@hidden        :
Unidata Program Center                        PH:303-497-8676        :
University Corp for Atmospheric Research      3300 Mitchell Ln       :
http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000  :
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