Scheduled NOAA-21 VIIRS and OMPS Data Outage

[kathys]

Topic: NOAA-21 VIIRS Mid-Mission Outgassing Activity Scheduled from February 26, 2024 to February 29, 2024

Date/Time Issued: February 13, 2024 02:22Z

Product(s) or Data Impacted: JPSS NOAA-21 VIIRS and OMPS Sensor Data

Date/Time of Initial Impact: February 26, 2024 00:00Z

Date/Time of expected end Time: February 29, 2024 23:59Z

Duration: 4 Days

Details/Specifics of change: On February 26, 2024, NOAA-21 will start a Mid-Mission Outgassing Activity as a routine procedure before the satellite is declared as the primary JPSS spacecraft later this year. During this activity, VIIRS will be in Outgassing Mode, and OMPS will be in DECOM (decontamination mode). The end time of the activity is approximate, and an updated notice will be issued during the course of the activity.

The following observatory systems will be affected on February 26, 2024:

• February 26, 2024 00:00Z – February 29, 2024 23:59Z, OMPS will be in DECOM (decontamination mode) and science data will not be available

• February 26, 2024 00:00Z – February 29, 2024, 23:59Z, VIIRS will be in Outgassing Mode, science data will not be available

[kathys]

We received updated information concerning the NOAA-21 VIIRS Mid-Mission Outgassing Activity:

UPDATE#1 Issued : February 23, 2024 2228Z: The NOAA-21 VIIRS Mid-Mission Outgassing Activity will commence on February 26, 2024, at 14:22 UTC.

Expected Science data outages:

OMPS: February 26, 2024, 14:22:02 UTC - February 28, 2024, 15:39:40 UTC
VIIRS: February 26, 2024, 16:05:21 UTC - February 28, 2024, 13:57:45 UTC

VIIRS Data will need to be validated after returning to nominal temperature levels.

If a Critical Weather Day is declared before the activity begins, it will be canceled. If a declaration is made after the activity starts, we will complete it.

[kathys]

Update #2 Issued 21 February 2024, 21:30 UTC: The NOAA-21 VIIRS instrument was placed in active mode on February 27 at 21:00 UTC. This science data is not considered valid until the instrument is returned to fully operational mode and has been assessed by Cal/Val teams.

While this NOAA-21 VIIRS Science data is available through High Rate Data (HRD), Direct broadcast (DB) users are advised that this is not yet cleared for operational use.

[kathys]

Update #3 Issued 28 February 2024, 1656 UTC : The NOAA-21 VIIRS outgassing activity was completed on February 28, 2024.

The NOAA-21 VIIRS instrument was placed in operational mode on February 27, 2024, at 21:00 UTC. OMPS was placed in operational mode on February 28, 2024, at 15:37 UTC.

While NOAA-21 High Rate data (HRD) is available, Direct broadcast (DB) users are advised that this NOAA-21 science data is not yet cleared for operational use.

[kathys]

Update #4 Issued 29 February 2024, 2126Z: All NOAA-21 OMPS Nadir Profiler (NP) SDRs and EDRs (V8Pro) and OMPS Nadir Mapper (NM) SDRs and EDRs (V8TOz & V8TOS) products are approved for operational use and the NDE/PDA subscriptions for these products will be enabled at 21:30 UTC, February 29, 2024.

Direct Broadcast (DB) users can use the equivalent OMPS Community Satellite Processing Package (CSPP) LEO products for operations.

NOAA-21 VIIRS cal/val evaluation continues and will need further coordination before it is ready for operational use.

[kathys]

Update #5 Issued March 06, 2024 2116Z:

All NOAA-21 VIIRS science products are approved for operational use and the NDE/PDA subscriptions for these products will be enabled at 21:00 UTC, March 06, 2024.

Direct Broadcast (DB) users can use the equivalent VIIRS Community Satellite Processing Package (CSPP) LEO products for operations. Users should update their Look-Up-Tables (LUTs) so that the NOAA-21 VIIRS Near Infrared bands are properly calibrated. To update the LUTs, make sure your CSPP SDR environmental variables are set as described in the Installation Guide, and execute:

sdr_luts.sh

These new LUTs should be included in the downloads:

VIIRS-SDR-CAL-AUTOMATE-LUT_j02_20190916141131Z_20240229030000Z_ee00000000000000Z_PS-1-O-CCR-6958-003-LE-PE_all-_all_all-_ops.bin
VIIRS-SDR-EMISSIVE-V2-LUT_j02_20230814000000Z_20230101000000Z_ee00000000000000Z_PS-1-O-CCR-6797-002-LE-PE_all-_all_all-_ops.bin

Full assessment of NOAA-21 EDRs is still ongoing, users will be notified if there is any issue identified.