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[IDV #UMO-750357]: data type for GOES channels

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  • Subject: [IDV #UMO-750357]: data type for GOES channels
  • Date: Mon, 28 Apr 2014 09:33:02 -0600
Hi Dave,

re:
> I downloaded some satellite images from openarchive.ssec.wisc.edu from
> GOES 13, 14, and 15, specifically water vapor channel.  Under the IDV
> Dashboard->Data Choosers, when I specify 6.5um IR Mid-level Water Vapor,
> there are 5 options for the Data Type that pop up:
> 
> 1. Raw
> 2. Radiance
> 3. Temperature
> 4. Brightness
> 5. All Types
> 
> I've done some research so I think I know what "Raw" is (10-bit GVAR
> count value 0-1023), and "Radiance",  (given the scaling coefficients in
> http://www.oso.noaa.gov/goes/goes-calibration/gvar-conversion.htm), and
> "Temperature".  But I'm not sure what "Brightness" is.

Brightnesses are raw values scaled to the 0-255 range.

re:
> Is there a formal description of these data types somewhere?

I think that NOAA sites that deal with GOES GVAR imagery would be
your best bet.

re:
> Thanks!  I
> make the data local and then pick them apart with an IDL routine, so it
> would be nice to know how they are derived, or if I need to modify them
> further.

One of the problems you will run into with using the IDV for locally stored
satellite imagery is its inability to work in calibrated units (e.g., 
Temperature
for IR images, etc.) for those images.  The 5 options for Data Type that
you see is provided by the server of the data which, in this case, is
McIDAS ADDE.

You have two options for working with "local" satellite imagery:

- install and configure McIDAS ADDE and then serve the imagery using
  it

  We distribute/support/develop McIDAS for the U.S. university community,
  and UCAR users are entitled to use it by virtue of our site license 
  with the software's owner/primary developer, the University of Wisconsin
  (UW) Space Science and Engineering Center (SSEC).  McIDAS-X (as the
  package is known) is the package that I support and develop.

- use SSEC's version of the IDV, McIDAS-V

  The reason that you could use McIDAS-V (aka McV) is that SSEC bundles
  ADDE servers with its McV distributions

Cheers,

Tom
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Ticket Details
===================
Ticket ID: UMO-750357
Department: Support IDV
Priority: Normal
Status: Closed