Re: [ldm-users] no-data values in GOES-16 in visible imagery

• To: Devin Eyre <Devin.Eyre@xxxxxxxxxxxx>, "ldm-users@xxxxxxxxxxxxxxxx" <ldm-users@xxxxxxxxxxxxxxxx>
• Subject: Re: [ldm-users] no-data values in GOES-16 in visible imagery
• From: Pete Pokrandt <poker@xxxxxxxxxxxx>
• Date: Mon, 02 Oct 2017 18:38:36 +0000
• Authentication-results: spf=none (sender IP is ) smtp.mailfrom=poker@xxxxxxxxxxxx;
• Spamdiagnosticmetadata: NSPM
• Spamdiagnosticoutput: 1:99

I just came across this document that describes a number of issues that they 
are still working on with the GOES-16 CMI data (the remapped, processed data 
that we get through NOAAPORT)


https://www.ncdc.noaa.gov/sites/default/files/attachments/README_ABI-L1b-CMI_Provisional_Maturity.pdf

GOES-16 ABI Level 1b (L1b) and Cloud and Moisture Imagery 
...<https://www.ncdc.noaa.gov/sites/default/files/attachments/README_ABI-L1b-CMI_Provisional_Maturity.pdf>
www.ncdc.noaa.gov
GOES-16 ABI Level 1b (L1b) and Cloud and Moisture Imagery (CMI) Release 
Provisional Data Quality July 10, 2017 Read-Me for Data Users The GOES-R Peer 
Stakeholder ...



Many of the issues that we've noticed (missing values in bright visible, 
striping, periodic callibration issues in the colder temps on IR channels, 
etc..) are known and documented here, and fixes are in development.


FYI.

Pete




<http://www.weather.com/tv/shows/wx-geeks/video/the-incredible-shrinking-cold-pool>--
Pete Pokrandt - Systems Programmer
UW-Madison Dept of Atmospheric and Oceanic Sciences
608-262-3086  - poker@xxxxxxxxxxxx


________________________________
From: ldm-users-bounces@xxxxxxxxxxxxxxxx <ldm-users-bounces@xxxxxxxxxxxxxxxx> 
on behalf of Pete Pokrandt <poker@xxxxxxxxxxxx>
Sent: Monday, October 2, 2017 1:01 PM
To: Devin Eyre; ldm-users@xxxxxxxxxxxxxxxx
Cc: Tim Schmit
Subject: Re: [ldm-users] no-data values in GOES-16 in visible imagery


Devin,


I've noticed this since we first started getting the imagery back in April. The 
problem is that the ABI instrument returns reflectance values that are greater 
than 1 (up to 1.25 or so) but the processing software that remaps the images 
and sends out over NOAAPort is currently clipping them at 1 and assigning any 
higher values a missing/out of range value (which unfortunately is zero)


My quick and dirty solution is replacing all 0 values in the image with 1's, 
since I'd rather see white in the middle of storms, at the expense of the dark 
(night) areas being white. The only time it really ended up being an issue was 
with the total eclipse, which progressed across the country in brilliant white 
on my images.


Supposedly this was going to be fixed in July, but so far it has not. Someday 
hopefully.


Pete



<http://www.weather.com/tv/shows/wx-geeks/video/the-incredible-shrinking-cold-pool>--
Pete Pokrandt - Systems Programmer
UW-Madison Dept of Atmospheric and Oceanic Sciences
608-262-3086  - poker@xxxxxxxxxxxx


________________________________
From: ldm-users-bounces@xxxxxxxxxxxxxxxx <ldm-users-bounces@xxxxxxxxxxxxxxxx> 
on behalf of Devin Eyre <Devin.Eyre@xxxxxxxxxxxx>
Sent: Monday, October 2, 2017 9:56 AM
To: ldm-users@xxxxxxxxxxxxxxxx
Subject: [ldm-users] no-data values in GOES-16 in visible imagery


I have seen that there are frequently no-data values in the middle of 
high-reflectivity areas in the visible imagery.  How are you dealing with this 
when creating graphics?

• References:
  • [ldm-users] no-data values in GOES-16 in visible imagery
    • From: Devin Eyre
  • Re: [ldm-users] no-data values in GOES-16 in visible imagery
    • From: Pete Pokrandt