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19990708: NOAAport Channel 4 NESDIS header discrepancy

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  • Subject: 19990708: NOAAport Channel 4 NESDIS header discrepancy
  • Date: Thu, 8 Jul 1999 13:47:07 -0600
Dear Ms. Hayes,

I am looking at the "Four Satellite Composite" imagery which is
broadcast on SBN channel 4. This imagery uses the polar stereographic
projection and is supposed to utilize the AWIPS grid 201 projection.

In the imagery products being broadcast on NOAAport, I find that
the LOV value (Octets 28-30) is 2492048, which represents a 
central longitude of projection being 110.7952W. Using this value
in our software generates an incorrect mapping. The grib users
document states that AWIPS 201 is supposed to have a central
longitude of 105.00W, and when I use that value for the imagery, the
projection and mapping of the imagery appears correct.

Can you tell me if in fact the header information being broadcast
for these products is incorrect? We would like to make our software
as robust as possible, and would like to use the header for determining
the appropriate projection.

Thanks you in advance,

Steve Chiswell
Unidata User SUpport