[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[McIDAS #WWL-217735]: pixel shift in Florida Satellite Water Vapor Imagery

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [McIDAS #WWL-217735]: pixel shift in Florida Satellite Water Vapor Imagery
  • Date: Wed, 10 Sep 2014 08:17:49 -0600
Hi Peter,

re:
> Thank you for your response.  We are going back and take a fresh look. It is
> good to have someone with experience look and help us assess what we have.

No worries.  I can send you the procedure I used to adjust the 3.9 um
images if you like -- it is very simple and does result in better
registration with the 10.7 um images from the same time.  And, the fog
product created from the combination of the altered 3.9 and original 10.7
um images is reasonable.  How good it is, of course, depends on the eye
of the beholder and what the purpose is.  For areas of widespread fog
(like in southern South Carolina for the 11:15Z image), a climatological
interpretation of the fog product should not be too uncertain.

re: using combinations of 3.9 and 10.7 um images to assess fog distributions
> This technique seems to be fraught with difficulties and frustrations.
> Moderate expectations are in order.  But we will try and get out of it what
> we can.

Multi-band combinations especially using IR channels is a standard analysis
technique, but like anything else their interpretations have to be tempered
by a knowledge of the uncertainties and assumptions involved.  I view the
process as being fundamentally the same as when working with most other kinds
of geo-scientific data.

Perhaps it would be useful for you to review/examine more closely the
set of altered 3.9 and original 10.7 um images and the fog products
created from them so you can better assess their usefulness?

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: WWL-217735
Department: Support McIDAS
Priority: Normal
Status: Closed