SNPP and NOAA-20 VIIRS calibration anomaly

VIIRS Sensor Data Record

SNPP and NOAA-20 VIIRS calibration anomaly

Postby jbraun » Fri Jan 17, 2020 10:02 am

Dear Colleagues,

This note is to let you know that VIIRS data from both SNPP and NOAA-20 are currently affected by a calibration anomaly. Yesterday we received this message from the NOAA VIIRS calibration team:

“There has been an anomaly in the VIIRS SDR reflective bands calibration for both NOAA-20 and S-NPP because of incorrect solar vector calculations since about 2020-01-16 0:00 UTC. For S-NPP VIIRS SDR, both radiance and reflectance products are affected because the RSB calibration coefficients have not been updated since 2020-01-16 0:00 UTC. For NOAA-20 VIIRS SDR, radiance products should not be affected by this anomaly, but the reflectance products are affected because of the solar zenith angle errors. The root cause of the problem is still not known and is under investigation. More information will be provided when it becomes available.”

VIIRS data are currently not usable as a result. The anomaly is being observed in global VIIRS data from both NOAA and NASA, as well as VIIRS data obtained from direct broadcast and processed by CSPP SDR.

At this time we do not know when the problem will be resolved.
jbraun
 
Posts: 82
Joined: Thu Sep 18, 2014 11:25 am

Re: SNPP and NOAA-20 VIIRS calibration anomaly

Postby jbraun » Fri Jan 17, 2020 12:24 pm

Notification from ESPC Operations:

Topic: VIIRS SDR reflective solar bands (RSB)

Date/Time Issued: January 17, 2020 1330Z

Product(s) or Data Impacted: VIIRS SDR reflectance/radiance products

Date/Time of Initial Impact: January 16, 2020 0000Z

Date/Time of Expected End: TBD

Length of Event: TBD

Details/Specifics of Change:

There has been an anomaly in the VIIRS SDR reflective solar bands (RSB) calibration for both NOAA-20 and S-NPP due to an unexpected change in the solar vector since about 2020-01-16 0:00 UTC. As a result, large errors in VIIRS SDR reflectance/radiance products have been observed which affect RSB based products. This anomaly appears to affect the OMPS SDR as well. ESPC Level 2 products using VIIRS RSB bands and OMPS level 2 products are degraded. The exact cause of this anomaly is still under investigation. Please stay tuned for further updates.

Contact Information for Further Information: ESPC Operations at ESPCOperations@noaa.gov and 301-817-3880

Web Site(s) for applicable information: N/A
jbraun
 
Posts: 82
Joined: Thu Sep 18, 2014 11:25 am


Return to VIIRS SDR

Who is online

Users browsing this forum: No registered users and 2 guests

cron