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20060111: AreaDirectory for NOAAPORT GINI images

>From:  Tom Whittaker <address@hidden>
>Organization:  SSEC
>Keywords:  200601111605.k0BG5s7u007185 McIDAS ADDE GINI sounder

Hi Tom,

Don asked me to respond to your questions below...

>Date: Wed, 11 Jan 2006 09:53:55 -0600
>From: Tom Whittaker <address@hidden>
>
>Hi Don...
>
>This has been fixed and tested against your GINI images.  The "rule" we 
>adopted is:  the number of bands in AreaDirectory word 13 is the number
>that will appear on each line.  More "band bits" might be set if the
>actual bands changes in the middle of the AREA file, as is does when
>AVHRR data switches between day and night.  Since we ignore the
>'line prefix' information, which contains the bands and their packing
>order on each line (which apparently can also change in one AREA file...ugh),
>we can live with this for now, as long as we only get single-banded
>images back from the ADDE server.

>Dave Santek was curious, however (and now, so am I):  since the GOES 
>sounder instrument only has about 20 'sounder bands', why are the
>"band numbers" in these GINI areas numbers like 57, 43, and 48?

I set the band based on Physical Element (PDB byte 4) information in
the GINI header as described in Table 4.7 of:

Interface Control Document for
AWIPS - National Environmental Satellite, Data and
Information Service (NESDIS)

AA0130008 CH-4
June 12, 2002

http://www.weather.gov/noaaport/document/icd_ch4.pdf

I seem to remember that I did not try to make the GINI sounder images
match the GOES sounder images because of a potential problem/usability
in GEMPAK (GEMPAK uses the satellite source and band ID to uniquely
identify images; if I matched GOES sounder information, GEMPAK would
not have known that the image was a GINI) when the GINI image was
IMGCOPYed to a McIDAS AREA.

>Are they some sort of derived product?

No, but they are remapped into a conical projection.

>Since the SATBAND file has no equivalent entries for these, perhaps you can
>find out what they are and we can update your ADDE server's file to include
>more info about what these "bands" have in them?...

Here is the correspondence between ADDE descriptor, band ID, and sounder
wavelength:

ADDE groups GINIEAST/GINIWEST

descriptor   band ID    wavelength description
------------+----------+------------------------------------
GxSNDVIS     59         GINI 10 km SOUNDER VIS Channel
GxSND398     57         GINI 10 km SOUNDER 3.98 um Channel
GxSND445     55         GINI 10 km SOUNDER 4.45 um Channel
GxSND651     52         GINI 10 km SOUNDER 6.51 um Channel
GxSND702     51         GINI 10 km SOUNDER 7.02 um Channel
GxSND743     50         GINI 10 km SOUNDER 7.43 um Channel
GxSND1103    48         GINI 10 km SOUNDER 11.03 um Channel
GxSND1406    43         GINI 10 km SOUNDER 14.06 um Channel

where 'x' -> E or W

Table 4.7 has the complete list of Physical Elements used in GINI images
broadcast through NOAAPORT.

>...or not...
>
>Anyways, have fun with whatever these data are...
>
>tom

I hope that this helps...

Cheers,

Tom
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