Year
Case Name | Opening Date | Last Update | Status | Description |
---|---|---|---|---|
TM_NPP_L1B_24284 | 2024-10-10 | 2024-10-10 | Note | VIIRS Black Marble Reprocessing 2024/226 - 2024/279 <h1>VIIRS Black Marble Reprocessing 2024/226 - 2024/279</h1> A significant drop was found in the SNPP Black Marble Night-time radiance data values VNP46A1 and VNP46A2 since July/August 2024 and is back to normal form the recent days. The drop is due to unexpected larger prediction error of calibration coefficients in LUT v3.1.0.35 delivered on Aug 9 after the <a href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=716)">S/C CDP Reset Anomaly</a> (07/24-07/29). VCST will deliver a new LUT update which will be used to reprocess impacted days, <br><ul><li>VNP46A1: August 13, 2024 (2024/226) - September 28, 2024 (2024/272)</li><li>VNP46A2: August 13, 2024 (2024/226) - October 5, 2024 (2024/279)</li> |
TM_NPP_L1B_24269 | 2024-09-25 | 2024-10-10 | Note | SNPP GPS Anomaly 2024/269 <h1>SNPP GPS Anomaly 2024/269</h1>The SNPP/VIIRS spacecraft's geolocation entered a degraded state starting 22:44:05z on September 24, 2024. The engineering team is planning for spacecraft recovery on Friday, September 27, 2024. All PDA OPS subscriptions for all S-NPP science products were disabled at 14:00z on September 25, 2024. Data assessment by Cal/Val teams will follow to ensure S-NPP products are meeting mission specs. The SNPP/VIIRS recovery updates will be provided when further information becomes available.<br><br><h2 style="text-align:center;">*** UPDATE 10/01/2024 ***</h2>SNPP recovery efforts were successful on Friday, September 27, 2024. Thorough geolocation assessment was performed on the SNPP data following the recovery to approve data for operational use. The geolocation residuals returned to nominal range at approximately 17:33Z on 09/27/2024 (Figure 1). The final outage range is 9/26/2024 00:00z to 9/27/2024 17:30z (inclusive).<br><br> |
TM_NPP_L1B_23227 | 2023-09-21 | 2023-09-21 | Note | 2023.227 SNPP Nighttime Data Gap On August 15th 2023, (2023/227) SNPP suffered data loss impacting granule 21:30. The instrument data was reprocessed from DOY 227/20:00z - 22:00z. The images below show the missing data over the Indian Ocean during the night-time orbit. BT bands and geolocation layers were reviewed. Granules 21:30 and 21:36 were found to contain a data loss in the geolocation and BT bands.The examples below show the data loss in L1 geolocation and BT band M13 for granule 21:30.<br><br><br><br> |
PM_NPP_L1B_15241 | 2015-08-31 | 2015-08-31 | Note | IDPS did not ingest 00Z Polar Wanderer ANC file for 8/28/15 IDPS did not ingest 00Z Polar Wanderer ANC file for 8/28/15, any data associated with this particular forecast will be degraded. IDPS Engineering unit is troubleshooting the problem. Land SIPS data should be ok.<br><br><br> |
PM_NPP_L1B_15178 | 2015-05-01 | 2015-05-01 | Note | Data loss on day 2015178 due to maneuver On Saturday, June 27th, 2015.178 Suomi-NPP performed a VIIRS Lunar Calibration Maneuver centered at 14:17:10 UTC. For data day 2015.178, L1B SDR granule with start time 14:10 could not be produced and granule 14:05 produced with a small data gap due to error in the RDR from routine lunar calibration on that day. This missing input data resulted in similar data gap in nearly all of the downstream, and in some cases adjacent granules may not been generated due to cross granule requirement in the processing. The image example below shows the period of data loss in the L1B reflectance product over the North Atlantic Ocean.<br> |
PM_NPP_L1B_15065 | 2015-03-11 | 2015-03-11 | Note | Out of sync LUTs 2015.065 to 2015.068 IDPS promoted a new version of the VIIRS-SDR-DELTA-C-LUT to their forward processing stream on 3.6.15 at 21:14. The LUT was installed at Land SIPS on 03.09.2015. Due to this delay the L1B SDRs and downstream products are out of sync from 03.06.15 (2015.065) to 03.09.15 (2015.068).<br><br><br> |
PM_NPP_L1B_15038 | 2015-02-20 | 2015-02-20 | Note | L1B Reflectance 2015.038, four anomalous granules On February 7th, 2015 (2015.038) a data issue was observed that includes granules reporting anomalous data values in the L1B reflectance bands. Four of the granules have been identified as 10:55 (Southeast Africa), 11:20 (Scandinavia), 14:40 (Ireland), and 22:40 (South Pacific Ocean). The global browse difference image for M1 of this day is the first image below, showing the anomalous granules. In each of these instances the IDPS (AS3000) granules report slightly lower values than the Land SIPS data in AS 3001. The next three images show an example of granule 10:55 from IDPS, Land SIPS and the difference granule. The issue effects the VIIRS I-Band and M-Band L1 Reflectance M bands as well as the Radiance band in the L1B VDNE product and it propagates downstream for the relative data products.<Br><Br> NOTE: The cause of this was traced back to the wrong set of VIIRS-SDR-F-PREDICTED-LUT and VIIRS-SDR-DNB-LGS-GAINS-LUT were used at Land SIPS. The LUTS from the prior week were staged and this effected 6 granules in total:(10:55, 22:40, 21:50, 23:30, 11:20, 14:40). These granules will not be reprocessed at this time. |
PM_NPP_L1B_15047 | 2015-02-16 | 2015-02-16 | Note | L1B out of sync LUTs 2015.043 to 2015.044 The weekly LUTs (the F-Predicted and LGS-GAIN) for PGE302 were installed at Land SIPS on 02.12.2015 at 23:57. Due to an error during install at IDPS there was a delay and the LUTS were put into operations at IDPS on 02.13.2015 at 1430. L1B SDRs and downstreams are out of sync due to out of sync LUTs for this period 02/12 (2015.043) to 02/13 (2015.044).<br><br><br> |
PM_NPP_L1B_15035 | 2015-02-04 | 2015-02-04 | Note | Data loss on day 2015030 due to maneuver On Friday, January 30th, 2015 at 08:17:14 UTC Suomi-NPP performed a VIIRS Lunar Calibration Maneuver. S-NPP was pointing off nadir and collected data from 08:17:14 to 08:29:14 UTC. The time period was reviewed for geolocation issues and no geolocation shift was detected in the downstream land data products. The L1B granules were also reviewed, and were found to be free of data corruption in the L1B geolocation, reflectance, and brightness temperature layers. However, users should be aware that granules 08:25 and 08:20 contain portions of fill values, and granule 08:15 was not produced. The image example below shows the period of data loss in the L1B reflectance product over the Indian Ocean. |
PM_NPP_L1B_15030 | 2015-01-30 | 2015-02-03 | Note | Striping L1B Reflectance 2015.030 Data issue that appears as a series of stripes in the LPEATE L1B data. LPEATE VIIRS I-Band and M-Band L1 Reflectance reports scan lines with slightly lower values. This issue was observed in granule 2155 passing over the Pacific Ocean and is seen in the down stream data products. The first image shows the LPEATE granule of the M band reflectance RGB bands (M5,M4,M3), where the stripes are observed. The next image shows the corresponding longitude geolocation data from the granule, which contains no issues. The last image is a spatial subset taken from the full resolution NPP_VMAE_L1.A2015030.2155 granule, this shows more clearly the striping. |
PM_NPP_L1B_15009 | 2015-01-09 | 2015-01-09 | Note | L1B out of sync LUTs 2015.007 to 009 L1B SDRs and downstreams potentially out of sync due to out of sync LUTs for the period 1/7 to 1/9. This stems from a change in the begin use time at IDPS for the weekly LUTs, VIIRS-SDR-F-PREDICTED-LUT and the VIIRS-SDR-DNB-LGS-GAINS-LUT. |
PM_NPP_L1B_14344 | 2014-12-15 | 2014-12-15 | Note | Suomi-NPP VIIRS flight software update, 12.10.14(2014.344) On Wednesday December 10, 2014 (DOY 2014.344) the VIIRS instrument transitioned to a new flight software version (Ver. x4016). The flight software update was not expected to impact the VIIRS data in general with the exception of periodic outages and degradation of the Day-Night Band. However, some degradation was observed in the L1B data during the transition windows as well as outages in the Day-Night Band. Below is a list of expected impacts:<br><br>VIIRS Data may be missing or corrupt during the following VIIRS flight software transition commanding windows:<br>SVL 16162: 13:08:48 - 13:22:59 UTC<br>SVL 16163: 14:50:48 - 15:04:23 UTC<br>SVL 16164: 16:34:09 - 16:46:16 UTC<br>SVL 16165: 18:17:38 - 18:28:17 UTC<br>SVL 16166: 20:00:25 - 20:11:33 UTC<br>SVL 16167: 21:42:27 - 21:55:23 UTC<br><br><br>The first image below shows the L1B granule that was found to be degraded during one of the transition windows. The second image is the associated geolocation information, where no degradation was observed. The third image shows the data outages observed in the Day-Night band for this day over Australia and Eastern Asia. |
PM_NPP_L1B_14326 | 2014-11-24 | 2019-02-11 | Note | Monthly DNB calibration activity The NASA V1 data contains data gaps in the aggregated L1B data due to the monthly DNB calibration activity (DNB cross calibrations X-Cal). There are three DNB calibrations each month that occur around the DNB dark offset measurements on new moon days. In one example for DOY 2014.326, the calibration activity is observed in granules 17:05 - 17:15, 0840 - 0850, and 0145 - 0205. This directly effects the downstream L2 products including LST, Surface Reflectance IP, and VI. For DOY 2014.326, the time of data loss due to calibration activities occurs during three daytime orbits over the East coast of North America, and both Northern portions of Western and Eastern Russia. Below are examples of the granule 1705, where the L1B RGB(M5,4,3) bands is shown next to the associated geolocation latitude layer. While the data loss is observed at the end of the granule, no issues were observed in the associated geolocation information during the calibration activity. The monthly calibration activities are more easily observed in the L1B global browse images and downstream products as small data gaps in the Northern Hemisphere between the late fall and early spring months. The third image below shows a global browse example of L1B NPP_VMAE for DOY 2014.326 where the data gaps from these calibration activities can be observed. <br><br>NOTE to USERS: For all dates and times impacted by the DNB calibration events please refer to this chart: <A href="https://landweb.modaps.eosdis.nasa.gov/dnbcali">DNB Calibration of VIIRS </A><br><br> |
TM_NPP_L1B_23207 | 2023-07-27 | 2023-08-21 | Note | 2023.207 SNPP data outage/delay On July 26th 2023 (2023207) SNPP VIIRS suffered data loss as a result of an anomaly that caused the spacecraft to enter a non-nominal state at ~2:03:33 UTC on Jul 26, 2023. SNPP VIIRS has been put back in full operational mode starting at ~ 16:50 UTC July 27 after recovering from the anomaly. Please note that as Land SIPS start operational forward processing of VIIRS data on 7/31 after recovering from the disk issues that had caused all processing (at MODAPS and Land SIPS) to cease on early July 21, resulting in a <b> permanent data gap in the SNPP VIIRS for the period ~2:03:33 UTC on Jul 26, 2023 through ~ 16:50 UTC July 27.</b> Further note that the products generated for the period after recovery from spacecraft anomaly could be reprocessed using the new LUT if it is deemed necessary (with recommendation from NASA VCST and land science team) following the completion of on-going assessment of the instrument performance by the NASA VCST. Processing was resumed with updated L1B LUTs that are to address the following post safe-mode impacts: RSB F-factors have small change in some detectors (~0.2% in M8). DNB DN0 of HGA & HGB have noticeable change that causing image striping. Listed below are updates from NOAA regarding the outage and anomaly status.<br><br><font color="red">Update #6 07/31/2023:</font> : As of Monday, July 31, 2023, all CrIS SDR and BUFR products are approved for operational use and NDE/PDA subscriptions for those products will be enabled at 17:30 UTC, July 31, 2023. All VIIRS EDR products are now approved for operational use and NDE/PDA subscriptions for all VIIRS science products will be enabled at 17:30 UTC, July 31, 2023. Direct Broadcast (DB) users can use the equivalent CSPP LEO products for operations. The OMPS SDR and EDR teams will evaluate OMPS Limb Profile (LP), Nadir Profile (NP), and Nadir Mapper (NM) product quality after the OMPS SDR Look Up Tables (LUTs) are ingested into operations later this week.<br><br><font color="red">Update #5 07/28/2023:</font> Engineering continued instrument science data activation activities for S-NPP. As of Friday, July 28, 2023, VIIRS SDR products are approved for operational use. Direct Broadcast (DB) users can use the equivalent Community Satellite Processing Package (CSPP) LEO products for operations. However, Cal/Val teams and PALs are continuing their analysis on VIIRS EDR products. NDE/PDA subscriptions for all VIIRS science products are expected to be enabled early next week. The OMPS SDR and EDR teams will evaluate OMPS Limb Profile (LP), Nadir Profile (NP), and Nadir Mapper (NM) product quality after the OMPS SDR Look Up Tables (LUTs) are ingested into operations mid next week. The CrIS instrument is showing nominal recovery, but Cal/Val teams will still need to conduct more analysis before all CrIS science products can be approved for operational use. The Global Browse image below shows full data recovery for July 28th, 2023.<br><br> |
PM_NPP_L1B_14304a | 2014-11-06 | 2014-11-06 | Note | slight difference in high latitude granules, 10.31.14 (2014.304) APU results from day 10/31/14 reveal a small, but insignificant difference for thermal bands in the image and moderate resolution L1B SDR generated at Land PEATE and IDPS . The plot below shows the NPP_VMAE_L1 Brightness Temperature band M14, where the difference of less than 0.0005 is centered at 261 K. The negligible mean difference is centered at a lower temperature below freezing, which could be caused by one or two granules located at very high latitudes that might have been generated using out of sync LUTs. The observed difference has not shown any impact on downstream products, the cause of this difference is under investigation. |
PM_NPP_L1B_14276 | 2014-10-14 | 2014-10-14 | Pending | LPEATE L1 High Latitude data loss DOY 2014276 The LPEATE L1 NPP_VMAE_L1 and NPP_VIAE_L1 products from day 2014276 contain granules at high latitude polar regions, which report horizontal stripes across the middle of the granule containing 0 data values. The first image below shows the IDPS AS 3000, NPP_VMAE Reflectance band M7 and the second image shows the LPEATE AS 3001, NPP_VMAE Reflectance band M7. The third image is the difference between the two granules, where these stripes are observed in the image across the bottom portion of the granule. The following example image below shows the NPP_VMAE brightness temperature band 14, where these stripes are more visible across the day night line in LPEATE AS 3001. And the final image is the latitude geolocation layer associated with this granule, which shows no artifacts in the related geolocation information. Currently 16 granules are being investigated for the cause of this data loss. <br><br>Granules Under Investigation:<br>A2014276.0425<br>A2014276.0430<br>A2014276.0605<br>A2014276.0610<br>A2014276.0750<br>A2014276.0930<br>A2014276.1110<br>A2014276.1250<br>A2014276.1430<br>A2014276.1435<br> |
PM_NPP_L1B_14282 | 2014-10-10 | 2014-10-10 | Note | VIIRS SBC lock-up, 10.09.14 (2014.282) VIIRS went to 'Petulant' Mode on 10/02/2014 (2014.282) at 17:22:07 GMT due to a VIIRS Single Board Computer (SBC) Lock-up anomaly. As a result, VIIRS science data output was impacted from 17:22:07 GMT to 23:00:00 GMT and no VIIRS data was collected for approximately two (2) hours and nine (9) minutes. Additionally, the VIIRS Day-Night Band data (DNB) will be degraded until approximately 23:00:00 UTC. The data regions impacted by this event are daytime orbits over North and South America. Additionally, Nighttime orbits over Asia are impacted. The images below show the impact of the event on the daytime surface reflectant and night time cloud mask data streams. Both the IDPS and LPEATE data archives will be impacted by this event. Additional granules impacted by the SBC lock-up include granules 1930 and 2255, which are shown below in the last two images containing artifacts of data loss across portions of the granule. However, no corruption in the geolocation information was observed for both of these granules.<br><br><br><br> NOTE: Processing did occur for 40 granules between 19:30 and 23:00; the 21:10, 22:45, and 22:50 granules did not process. Data Hidden From Production : 17:20 - 19:30, 21:05 - 21:15, 22:45 - 23:00<br><br><br><br> |
PM_NPP_L1B_14269 | 2014-09-29 | 2014-09-29 | Note | VIIRS went to 'Petulant' Mode, 09.26.14 (2014.269) VIIRS went to 'Petulant' Mode on 09/29/2014 (2014.269) at 16:20:00 GMT. As a result, VIIRS science data output was impacted from 16:20:00 GMT to 18:35:00 GMT. The data regions impacted by this event are nighttime orbits over Asia including India, China and Southeast Asia and Australia. Additionally, Daytime orbits over North and South America are impacted. The images below show the impact of the event on the daytime surface reflectant and night time cloud mask data streams. Both the IDPS and LPEATE data archives will be impacted by this event. <br><br><br><br> |
PM_NPP_L1B_14254 | 2014-09-12 | 2014-09-12 | Note | Corrupt data on day 2014253 due to maneuver On Wednesday, September 10, 2014 at 18:54:35 UTC Suomi-NPP performed the second of a series of critical mandatory out-of-plane maneuvers to maintain a mean local time requirement. S-NPP was pointing off nadir and collected data from 18:41:35 to 19:09:12 UTC. The L1B Thermal bands and geolocation were reviewed and granules between the time period 18:40 - 19:00 were found to contain corrupt geolocation and impacts to the L1B brightness temperature. The example below shows the period of data loss in the L2 nighttime Cloud Mask product over Asia and portions of the Indian Ocean. |
PM_NPP_L1B_14220 | 2014-08-08 | 2014-08-11 | Note | August 08, 2014 (2014.220) VIIRS instrument entered safe mode. On August 8th, 2014 (2014.220) the VIIRS instrument entered safe mode starting at 1420 UTC. After a scheduled drag maneuver, the spacecraft unexpectedly went into Safe Mode and was in Earth Point. There will be no Science Data between 1420-1845 in AS 3001 and 1410-1850 for AS 3000. This data outage is observed in the L1 data and all downstream data products during the daytime over North and South America and at night time over Australia, Southeast Asia and China. <br><br> <br><br> NOTE: The original data outage period was reported between 14:20 and 1845. However, the night time L2 data products such as the Cloud Mask NPP_CMIP_L2 and the night time LST show the data gap period extending to granule 19:15. The first and second images below show the global browse image for day (L1B) and night (L2 Cloud Mask) for dat 20145.220, where the data outage is observed over Asia and the Americas. The third image below is granule L2 night time Cloud mask granule 19:15 over the Indian Ocean, where a data gap is observed in a portion of the granule.<br><br><br><br> |
PM_NPP_L1B_14211 | 2014-08-01 | 2014-08-01 | Note | Missing data on day 2014211 due to maneuver On Wednesday, July 30, 2014 at 18:41:32 UTC Suomi-NPP performed the first of a series of critical mandatory out-of-plane maneuvers to maintain a mean local time requirement. The primary scheduled burn opportunity ( S-NPP pointing off nadir 18:31:21 - 18:56:29) was not executed due to a loss of communication prior to activating the burn. A secondary maneuver ( S-NPP pointing off nadir 21:54:20 - 22:19:28) was executed successfully. Both the primary and secondary maneuver periods occurred during night time orbits and data losses for both periods are observed in the night time data products such as the L2 Cloud Mask, and Land Surface Temperature. Users should be aware of these maneuver periods and the data loss associated with these two night time maneuver periods. The example below shows the two periods of data loss in the L2 nighttime Cloud Mask product. |
PM_NPP_L1B_14196 | 2014-07-22 | 2014-07-22 | Note | Striping / data loss observed in night time cloud mask, 7/15 (2014.196) Data issue that appears as a series of data gaps in the VIIRS LPEATE (AS 3001) L1B thermal bands and downstream products. This issue was observed in two night time orbits passing over the South Pacific and Eastern Australia from times 13:20 to 15:20. The striping and data loss originates upstream where the issues is first observed in the L1B thermal bands. The data loss propagates downstream to the L2 CMIP product as well as the night time L2 LST. The first image below shows the LPEATE L1B granule of the thermal brightness temperature band 12. The second image shows the same granule for the L2 Cloud Detection Results & Confidence Indicator for time 15:05 over Eastern Australia where this data gap and striping occurs. The third image is the associated geolocation information, which shows no issue in the L1 geolocation information. The cause of the L1B and L2 cloud mask striping and data loss issue is currently under investigation. <br><br><br><br> |
PM_NPP_L1B_14079 | 2014-03-20 | 2014-03-20 | Note | NPP_OPS reduction of the IDPS AS3000 processing, day 2014.076 Due to data redundancy, NPP operations will start de-scoping the IDPS AS3000 data stream on day 2014.076, (03.17.14). The Day Of Year 2014.075 (03.16.14) is the last full day of daily processing in AS3000. AS3000 DOY 076-079 will be utilized for configuration testing and some of this data will be produced during this testing. However, the daily L1 data and downstream data products for days 076-079 in AS3000 will be incomplete and the AS3000 global browse images for day 2014.076 reflect this. Moving forward, DOY 080 (03.21.14) will be the first full day of the new weekly, single day processing of AS3000. NPP operations will only produce the IDPS AS3000 data products once a week. The LPEATE AS3001 will continue to be produced daily, and there will be no change in this processing stream. <br><br><br><br> |
PM_NPP_L1B_14037 | 2014-02-06 | 2014-02-06 | Note | VIIRS went to 'Petulant' Mode, 02.04.14 (2014.035) VIIRS went to 'Petulant' Mode on 02/04/2014 (2014.035) at 17:37:44 GMT. As a result, VIIRS science data output stopped at 17:37:44 GMT and resumed at 21:35:02 GMT. Degradation is expected for multiple, subsequent orbits (particularly in the DNB). The data regions impacted by this event are nighttime orbits over Asia including India, China and Southeast Asia. Additionally, Daytime orbits over North and South America. The images below show the impact of the event on the daytime surface reflectant and night time cloud mask data streams. Both the IDPS and LPEATE data archives will be impacted by this event. <br><br><br><br> |
TM_NPP_L1B_23186 | 2023-07-07 | 2023-07-07 | Note | 2023.186 data loss On 2023/186 (07.05.23) SNPP VIIRS instrument experienced a 2 minute data loss during a nighttime orbit over the South Pacific Ocean from 09:11:04z - 09:13:35z. The data is unrecoverable and affects granules 09:06 and 09:12. This data loss will impact all L1B and downstream products for the listed period in both C1 and C2 collections.<br><br><br> |
PM_NPP_L1B_14016 | 2014-01-16 | 2014-01-16 | Pending | Data Gap in IDPS and LPEATE, day 2014.012.0435 IDPS and LPEATE L1 data from DOY 2014.012 contains a data gap in the aggregated Thermal BT bands for L1B data in granule 04:35. This directly effects downstream L2 products including LST, Surface Reflectance IP, and VI. The time of the data loss occurs during the daytime, over Australia. Below are examples of the granule 0435 for IDPS and LPEATE. First, the L1B Brightness Temperature M15 band for the IDPS granule is shown next to the LPEATE granule where the data loss is observed in the middle of the granule. The third and fourth images show the latitude geolocation layers for IDPS and LPEATE, where no data loss is observed. The cause of this data loss is under investigation. |
PM_NPP_L1B_13255 | 2013-09-12 | 2013-09-12 | Note | IDPS and LPEATE LUT Mismatch, 09.06.13 (2013.249) Starting on day 9/06/2013 The L1B SDRs from IDPS and Land PEATE have noticeable differences in almost all of the spectral bands (I, M and DNB). This is resulting from a LPEATE production error caused by system failure to sync all minions with new LUT on 9/6/13, which caused minions at random to use older LUTs while processing the L1B for data day 9/6. LDOPE is currently working to identify the date/time when all minions started using the new LUT. As of 9/12 all minions are using the new LUT.<br><br><br><br> |
PM_NPP_L1B_13247 | 2013-09-06 | 2013-09-10 | Note | Permanent data loss in IDPS archive due to core issue, day 2013.247 IDPS data from DOY 247 contains a gap in the aggregated data for most of the L1/L2 products from 05:50 - 06:00, orbit 9503. The data has been lost due to a core issue at IDPS. However, LPEATE did receive all of the RDRs for this day and in the LPEATE stream there is no data gap observed. The time of the data loss occurs in the Northern Latitudes at night, over portions of Greenland and eastern Canada.<br><br>The data gap is observed in the IDPS night time L1B latitude geolocation layer and the downstream cloud mask product for granules times 05:50 and 05:55 of day 2013.247. Below are examples of the granule 0555 for IDPS and LPEATE. First, the L1B IDPS granule of the BT band M13 is shown next to the LPEATE granule. The third and fourth images show the latitude geolocation for IDPS and LPEATE, where the data gap is observed in IDPS only. Next, the last two images show the downstream data gap observed in the IDPS cloud mask image. |
PM_NPP_L1B_13228 | 2013-08-19 | 2013-08-20 | Note | IDPS and LPEATE LUT Mismatch The L1B SDRs from IDPS and Land PEATE have noticeable differences in almost all of the spectral bands (I, M and DNB) resulting from the use of incorrect Calibration LUTs at Land PEATE starting on data day 8/16/2013. Land PEATE is currently working to track down and install the same LUT as used by IDPS.<br><br><br><br> Note: The weekly LUTs were installed on 8/19/13 17:32 at IDPS to match the current operating version of LPEATE. This issue has been resolved.<br><br><br><br> |
PM_NPP_L1B_13220 | 2013-08-09 | 2013-08-09 | Note | Differences in L1B data due to Dual Gain Anomaly LUT update data day 2012.220 On August 8th, 2013 IDPS promoted a new VIIRS-SDR-DG-ANOMALY-DN-LIMITS-LUT to operations (data day 2013.220). The dual gain anomaly LUT went into operations at IDPS with a start time of 2013.220.1920. LPEATE plans to promote the LUT into operations on data day 2013.221. During this period minor differences can be observed in the L1B data between IDPS and LPEATE. The small differences can be detected through review of the SDR quality flag. The images below show an example of the difference detected in the quality flags for reflectance M band 5 between IDPS and LPEATE. |
PM_NPP_L1B_13217 | 2013-08-05 | 2013-08-05 | Note | Some IDPS and LPEATE granules differ in size Some IDPS and LPEATE granules differ in size. This is due to the different number of unaggregated 86 second granules that make up the IDPS granule, which varies from the total found in the LPEATE granule. The example below shows the 17:25 granule of data day 2013.208 over the Antarctic, where the LPEATE granule is smaller than IDPS because it contains 3 aggregated time segments, while the IDPS granule is composed of 4 time segments. This occurrence is not a L1 data quality issue, however users should note that this issue is consistently observed near the polar regions in the global browse image and may be mistaken as missing data. |
PM_NPP_L1B_13213 | 2013-08-01 | 2013-08-01 | Pending | Striping in VIIRS I and M-Band L1 Reflectance reports fill value in LPEATE only (MISS_UINT16_FILL 65534) Data issue that appears as a series of data gaps in LPEATE and not in IDPS. LPEATE VIIRS I-Band and M-Band L1 Reflectance reports a MISS_UINT16_FILL 65534 fill value. This issue was observed in 2 granules passing over Africa and is seen in the down stream data products. The first image shows the LPEATE granule of the M band reflectance RGB bands (M5,M4,M3), where the 65534 fill value is shown as stripes. The next image shows the corresponding latitude geolocation data from the granule, which contains no issues. The next two images show the same granules for the IDPS AS 3000. |
PM_NPP_L1B_13207 | 2013-07-26 | 2013-07-26 | Note | Brightness Temperature Band discrepancy July 10th, day 2013.191 On July 10th, day 2013.191 a discrepancy was observed in the Brightness Temperature bands between IDPS and LPEATE. This difference in BT bands effects the L1B data from day 2013.191 and forward. It was confirmed that a change in the IDPS MX7.1 versions Black Body LUT caused this discrepancy as Mx7.1 was promoted to IDPS OPS on 07/10/13. Land PEATE is currently working to put the new Mx7.1 build into operation and this is expected to occur the first week of August. |
PM_NPP_L1B_13198 | 2013-07-17 | 2013-07-17 | Note | Incorrect LUT used to produce Mx6 Level 1B on 2013.186 The TOA reflectance/radiance in the SDR produced at Land PEATE and IDPS for the data days 2013186 - 2013193 show minor difference, possibly due to difference in the weekly update to LUT (H-LUT and predicted F-LUT) put in operation on July 5. Issue is currently being investigated. |
PM_NPP_L1B_13198c | 2013-07-17 | 2013-07-18 | Note | Incorrect LUT used to produce Level 1B on July 12th, day 2013.193 The TOA reflectance/radiance in the SDR produced at Land PEATE and IDPS for the data days 2013193 onwards show minor difference resulting from failure to put the weekly update to LUT (H-LUT and predicted F-LUT) put in operation on July 12 at Land PEATE. <br><br><br>NOTE: The LUT was put into operation at Land PEATE on 7/17 (198), this discrepancy has been resolved.<br><br><br> |
PM_NPP_VAFIP_22225 | 2022-09-12 | 2022-09-12 | Note | Data gaps in VNP14IMG due to false fire detection, I5 band Data gaps have been observed in the C1 VNP14IMG product for specific granules, which contain a small stripe of anomalously high values in the upstream L1B I5 BT band. Due to this stripe of anomalously high data values in the L1B I5 band, the associated downstream VNP14IMG product is not produced as these granules are flagged as containing too many false fires detected. In these cases, the VNP14IMG granule will not be produced and the global browse image will show a data gap, associated with each missing granule. The first image below shows the global browse image of the C1 VNP14IMG product for DOY 2022.241(08.29.22), where a VNP14IMG data gap occurs over North America for granule 20:24. Users should note that processing of the same product using the NASA L1B (VNP02IMG, AS5200) in C2, is not expected to produce any such false fire gap because the same scan lines in the NASA L1B (C2) records a fill value of 65534, and this will allow the downstram processing of the VNP14IMG granule.<br><br> |
CC_NPP_L1B_13172 | 2013-06-21 | 2013-06-21 | Note | Missing data on day 2013167 There are several intervals of missing data on data day 2013167 (June 16, 2013). All of these intervals are during nighttime periods, along a line of nearly consistent latitude. The first two images below, the global browses for nighttime cloud mask and nighttime land surface temperature from 2013167, illustrate this pattern. Examples of affected individual granules are shown below the global browses.<br><br>The affected granules are 14:30, 16:10, 17:50, 17:55, 19:30, 19:35, 21:15, and 22:55. For some of these granules, more data are missing from band M13 than from the other bands in the range M12- M16. The geolocation data are present during the periods of missing data, and there are no geolocation artifacts.<br><br>Fill values are shown in red in all granule images. |
PM_NPP_L1B_13156 | 2013-06-05 | 2013-06-10 | Pending | Data loss due to DAS upload There was a data loss that occurred on day 05.30.13 (2013.150). The data outage occurred over Antarctica during a daytime acquisition between 17:47:05 and 17:52:45 and is due to a DAS upload, which is a data loss from the turning off of the SMD output during on-board DAS command upload. In the example below the data outage is associated with the loss of geolocation information of the two granules, 1745 and 1755. <br><br><br><br> |
CC_NPP_L1B_13143 | 2013-05-23 | 2013-05-23 | Note | Granules 2013141 0835 and 0840 missing due to sector rotation Due to a sector rotation for a lunar observation on May 21, 2013 (2013141), granules 08:35 and 08:40 for that day were not produced. The missing data are over southwestern Asia. The global browse images of moderate- resolution (NPP_VMAE_L1) and imagery- resolution (NPP_VIAE_L1) SDR data for 2013141 are shown below. The NPP_VMAE_L1 global browse is on the left and the NPP_VIAE_L1 browse is on the right. |
PM_NPP_L1B_13123 | 2013-05-03 | 2013-05-03 | Pending | Artifacts in the polar regions are due to global browse image projection code The NPP global browse (IDPS and LPEATE) L1 images contain checkerboard artifacts in the polar regions due to the projection handling of multiple overlapping granules. This issue is only present in the global browse image and is NOT present in the L1 data or downstream production. The first image below is a spatial subset of the NPP_VMAE L1 global browse image showing the artifact as a purple square over Greenland on day 2013.119. The second image below is the full resolution granule, time period 1405 on the same day. The artifact is not present on the full resolution granule. This issue is currently under investigation. |
PM_NPP_L1B_13080 | 2013-03-21 | 2013-08-01 | Note | Striping in VIIRS I and M-Band L1 Reflectance reports fill value (MISS_UINT16_FILL 65534) Data issue that appears as a series of data gaps in IDPS and LPEATE VIIRS I-Band and M-Band L1 Reflectance reports a MISS_UINT16_FILL 65534 fill value. This issue was observed in 3 granules passing over South America and is seen in down stream data products. The first image shows the IDPS granule of the M band reflectance RGB bands (M5,M4,M3), where the 65534 fill value is shown as the white stripes. The next image shows the corresponding latitude geolocation data from the granule. The next two images show the I-Band RGB bands(1,2,1) and the corresponding IMFT geolocation information. Both the L1 M and I-Bands geolocation layers do not show fill values. The last four images show a similar example for the LPEATE AS 3001. |
CC_NPP_L1B_13056 | 2013-02-25 | 2013-02-28 | Note | Granules 2013052 09:25 and 09:30 not useful Earth- view data due to maneuver Due to a sector rotation during a lunar calibration maneuver, granules 2013052 09:25 and 2013052 09:30 contain data in which the center of the scan is at the Earth limb and nadir is at the edge of scan. The transition periods at the beginning and end of this configuration are fill values. Geolocation values are inaccurate or fill throughout this period. The first three images show granule 09:25 band M1 radiance, latitude, and longitude. The second three images show granule 09:30 M1 radiance, latitude, and longitude. Fill values are shown in red. |
CC_NPP_L1B_13010 | 2013-01-10 | 2013-01-10 | Note | Missing data on day 2012358 due to maneuver Due to a lunar roll/ sector rotation maneuver carried out on December 23, 2013 (2012358), data are missing from about 14:55 through 15:10. The 2012358 NPP_VMAE_L1 global browse image below shows the missing data as a gap over the southern Atlantic Ocean. |
CC_NPP_L1B_13003 | 2013-01-03 | 2013-01-10 | Note | Missing data, day 2012360 There was a brief VIIRS SDR data loss at approximately 12:45 on 2012360. The NPP_VMAE_L2 global browse image for that day is shown below, illustrating the data gap over southwestern Africa on 2012360. The gap is due to bad Level 1B data from IDPS. Radiance values were out of range and reflectances were fill values for all bands. |
PM_NPP_L1B_12331 | 2012-11-26 | 2012-11-26 | Note | Permanent data loss due to Petulant Mode anomaly on day 2012.327 There was a permanent VIIRS data loss due to a Petulant Mode anomaly for the period 2012.327 16:27 until 2012.327 22:15. This resulted in a daytime data loss over the majority of North and South America and a nighttime data loss over Asia. The missing data granules are shown below in the global browse images for this day. |
CC_NPP_L1B_12249 | 2012-09-06 | 2012-09-07 | Note | Incorrect LUT used to produce Mx6 Level 1B From the beginning of Mx6.2 production at IDPS (August 9, 2012 at 16:18:40), an incorrect LUT was used to produce Level 1B data at IDPS. This incorrect LUT affected reflective bands only. Reflective band values will be slightly off from their correct values. The Mx6.2 build used the pre-launch RSR LUT instead of using the one from Mx5.3. For more details see DR #4892. |
PM_NPP_L1B_22251 | 2022-09-09 | 2022-10-05 | Note | VIIRS Collection 2 (C2) Land reprocessing LandSIPS has started the VIIRS Collection 2 (C2) Land reprocessing for both SNPP and JPSS J1 (J1). The initial phase of reprocessing will cover the joint mission period from year 2018 up to the leading edge, followed by a second reprocessing stream covering the SNPP mission period from the beginning of 2012 till end of 2017. This reprocessing effort will use the C2 L1 Geolocation/L1B products as inputs for SNPP and the Collection 2.1 (C2.1) L1 Geolocation and L1B inputs for J1.<br><br>The initial reprocessing will cover the Tier1 suite of products, which include LSR, Lai/Fpar, VI, Active-Fire, LST, BRDF, VIIRS Water Reservoir, Sea-ice and IST products. A second Tier2 will include the DSR/PAR, MAIAC, Burned Area, GPP/NPP, ET/PET and the DNB suite of products. The Tier2 products will be made available as and when they are ready.<br><br>For further details on the C2 specific changes made to the different land science algorithms, users are requested to check <A href="https://landweb.modaps.eosdis.nasa.gov/data/userguide/VIIRS_Land_C2_Changes_09152022.pdf">this C2 description document.</A><br><br> |
PM_NPP_L1B_12227 | 2012-08-20 | 2012-08-20 | Pending | Data gap identified in IDPS and LPEATE Archive sets 08/14/2012 A data gap was observed in the global browse on 08/14/12. This loss occurs over the Atlantic ocean in granule 2012.227.1610. No geolocation issues were found in the review of the associated lat and long files. NPP_VMAE_L1 reflectance bands were reviewed and fill value 65534 was reported during the time of the data loss. This fill value is defined at a pixel level, as missing at time of processing. Where "C3S provided a fill value, the S/C did not provide the value, or AP missing." The root cause of the data loss is still under investigation and the data loss is observed in both the IDPS /LPEATE archive sets and down stream products. The example below shows granule NPP_VMAE_L1_A2012227_1610 from IDPS. The Red stripe shows fill value 65534 in the middle of the granule. |
PM_NPP_L1B_12177 | 2012-06-25 | 2012-06-26 | Pending | Spacecraft Anomaly occurred June 21, 2012 / VIIRS instrument entered safe mode. A Spacecraft Anomaly occurred Thursday, June 21 and the VIIRS instrument entered safe mode starting June 21 18:00 GMT until June 22, 14:43:17 GMT. Science data was not generated during these time periods, and therefore there will be data gaps. These data will not be recovered. Root cause of the anomaly is still under investigation. |
PM_NPP_L1B_12128 | 2012-05-07 | 2013-09-19 | Pending | LPEATE / IDPS, Rotating Telescope Assembly (RTA) and Half Angle Mirror (HAM) synchronization loss There is an occasional VIIRS RTA / HAM synchronization loss that results in a data loss of L1B data for both the IDPS and LPEATE data archives. Raytheon and NICSE/GEO are currently investigating this issue. Below are two examples of the data loss, the first image shows the IDPS VIIRS VMAE_L1 M13 (BrightTemp_Mod_M13) granule from DOY 2012.099.2035. The second image is the corresponding LPEATE granule. Both granules report a fill value of -999.5 over areas where the loss occurs. The third image shows the IDPS VIIRS VMAE_L1 M13 (Radiance_Mod_M13) granule from DOY 2012.099.2035, and the fourth image shows the corresponding radiance granule from LPEATE.<br><br><br><br> |
CC_NPP_L1B_12088 | 2012-03-29 | 2012-03-29 | Pending | Some IDPS and LPEATE granules differ in size; granules may have fill value padding Some IDPS and LPEATE granules differ in size. In addition, some granules have fill value padding appended to data fields. An example is shown below. The first row of images is from IDPS SDRs for date/ time 2012041 12:30 and 2012041 12:35. In this case, the 12:30 granule contains an area of fill values at the bottom of the granule. The LPEATE SDR for the same two granules is shown below. The dividing line between the 12:30 and 12:35 granules is different between IDPS and LPEATE, and the 12:35 granule is smaller in LPEATE than in IDPS. |
PM_NPP_L1B_12083a | 2012-03-23 | 2012-03-23 | Pending | LPEATE / IDPS Calibration LUT issue Day 2012.054 - 059 There may be an issue with identifying the correct LUT for time periods 054-059. Difference can be detected with slight differences in values between IDPS and LPEATE L1 (VMAE and VIAE) granules from time periods 037-059, and is clearly seen on a global scale. This issue was to be corrected starting on day 2012.054, however this issue still exists from day 54 to day 059. While there may have been some issue with identifying the correct LUT at Land PEATE, the PEATE will reprocess this period with the LUT used at IDPS. |
PM_NPP_L1B_12083 | 2012-03-23 | 2012-03-23 | Pending | LPEATE / IDPS Calibration LUT issue Day 2012.054 - 059 There may be an issue with identifying the correct LUT for time periods 054-059. Difference can be detected with slight differences in values between IDPS and LPEATE L1 (VMAE and VIAE) granules from time periods 037-059, and is clearly seen on a global scale. This issue was to be corrected starting on day 2012.054, however this issue still exists from day 54 to day 059. While there may have been some issue with identifying the correct LUT at Land PEATE, the PEATE will reprocess this period with the LUT used at IDPS. |
PM_NPP_L1B_12079 | 2012-03-20 | 2014-04-15 | Pending | A step pattern of anomalous data segments DOY 2012064, 094 A set of granule segments which occur over similar latitudes are degraded in the IDPS L1B data. The downstream effects of this degradation varies from instance to instance. Generally, in the observed instances the IDPS archive is not able to retrieve segments of the L1B Imagery granules, and the IDPS L1B Moderate granule segments show significantly different values when compared to the entire granule. In these instances, the LPEATE archive set is able to retrieve these same segments for both L1B products. The first example below shows the global browse image of the IDPS L1B Imagery band where the non retrieval segments are observed on a global scale. The second example below shows the IDPS L1B Moderate granule segments with significantly different values when compared to LPEATE. |
PM_NPP_L1B_12080b | 2012-03-20 | 2012-03-20 | Pending | IDPS, NPP_VIAE_L1 / NPP_VMAE_L1 missing geolocation data 2012.060.1815 IDPS granule 18:15 contains fill values in the L1 VMAE M and I bands for DOY 2012060 due to missing geolocation information. The data issue seen only in IDPS, is traced back to the geolocation data for both the VMAE and VIAE IDPS products. The first image below shows the VMAE granule RGB bands (M5,M4,M3). The stripes containing fill values are noted and match the missing geolocation stripes shown in the next image of the latitude granule. The third image shows a RGB composite bands (I1,I2,I1) of VIAE. Stripes containing fill values are listed, which are associated with the missing geolocation data shown in the fourth image of longitude from the NPP_IMFT_L1 granule. |
PM_NPP_L1B_12073a | 2012-03-13 | 2012-03-13 | Pending | VIIRS 1394 anomaly 2012.070: IDPS / LPEATE Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. VIIRS was restarted successfully and science data resumed at 14:03Z. No VIIRS data was received for Saturday, March 10, from 04:13Z to 14:03Z as a result of this anomaly. |
PM_NPP_L1B_12073 | 2012-03-13 | 2012-03-13 | Pending | VIIRS 1394 anomaly (2011.329, 2012.049, 2012.070) Occurrence 1) DOY 2011.329 Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. As a result of this anomaly no VIIRS data was received for November 25th 2011, from 16:30 to 23:45. <br><br><br> Occurrence 2) DOY 2012.049 Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. No VIIRS data was received for February 18th, from 04:10 to 12:05 as a result of this anomaly.<br><br><br> Occurrence 3) DOY 2012.070 Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. VIIRS was restarted successfully and science data resumed at 14:03Z. No VIIRS data was received for Saturday, March 10, from 04:13Z to 14:03Z as a result of this anomaly.<br><br><br> |
PM_NPP_L1B_22207 | 2022-07-27 | 2022-08-26 | Note | VIIRS safe mode, 07.26.22 (2022.207) The SNPP spacecraft entered non-nominal state on 07/26/2022 (2022.207) at 16:24:49 UTC, after which all SMD and telemetry data was inaccessible. The root cause continues to be investigated, subsequent contacts have confirmed that the spacecraft and all instruments, including VIIRS, are currently in a safe mode state. Engineering will continue to restore all instruments and science data to an operational state once a plan forward has been determined. The global browse images below show the operational AS5000 L1B daytime reflectance M(5,4,3) bands and nighttime emissive band M13 for SNPP VIIRS DOY 2022.207 (07.26.22). The data gap from this event is observed over the western hemisphere during the day and eastern hemisphere during the night orbits. The impacts from this event will affect all SNPP VIIRS operational archives. The data loss from this event will not be recoverable, and this note will be updated with the details of the data loss when more information becomes available. Impacts to the NRT products can be found <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=332"> here.</A><br><br> |
PM_NPP_L1B_12073c | 2012-03-13 | 2012-03-13 | Pending | VIIRS 1394 anomaly 2011.329: IDPS / LPEATE Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. As a result of this anomaly no VIIRS data was received for November 25th 2011, from 16:30 to 23:45. |
PM_NPP_L1B_12073b | 2012-03-13 | 2012-03-13 | Pending | VIIRS 1394 anomaly 2012.049: IDPS / LPEATE Data problem that appears as missing granules in the global browse images is due to a Anomaly Single Board Computer (SBC) lockup. No VIIRS data was received for February 18th, from 04:10 to 12:05 as a result of this anomaly. |
PM_NPP_L1B_12066 | 2012-03-07 | 2012-03-07 | Pending | LPEATE/ IDPS multiple data gaps DOY 2012046 There are multiple data gaps in LPEATE and IDPS VMAE L1 data from the orbit period 17:20 to 18:05 on 2012046. The cause of the data loss seen in LPEATE and IDPS is unclear and is currently under investigation.<br><br> The fill values detected are show in the images below, the explanation of each fill value is as follows.<br>Red: -999.4 : At the pixel level, the ellipsoid intersection failed because the observation does not intersect the earth's surface. This is an indication of a calibration maneuver.<br>Green: 65529: The pixel value does not exist because the data was not available - it is not missing, nor is any attempt made to calculate the data.<br>Blue: 65530: At the pixel level, the ellipsoid intersection failed because the observation does not intersect the earth's surface. This is an indication of a calibration maneuver.<br>Orange: 65531: The algorithm could not compute the pixel/cell because of a software or hardware problem (e.g., could not converge to a solution).<br>Red: 65534: The pixel was missing at the time of processing, where C3S provided a fill value, the S/C did not provide the value, or the AP missing.<br><br>The first and second images below show RGB reflectance bands M5, M4, and M3 from granule 2012046 17:45 (covering a portion south America and the Caribbean), with the LPEATE data on the left and IDPS on the right. The second and third images show the longitude of bands of granules 2012046 17:45 showing the data gap fill values (-999.4) as red, again LPEATE on the left and IDPS on the right. The fourth and fifth images show M bands 4, reflectance from granule 2012046 17:45. The LPEATE image on the left contains fill values 65534:red, 0:Yellow. The IDPS image on the right contains fill values 65529:green, 65530:blue, 65531:orange, and 65534:red. <br><br> The difference detected between the LPEATE and IDPS archives are understood more clearly in the M4 reflectance image examples (5 and 6). The two archives share the same indication of a calibration maneuver fill values (-999.4). However, LPEATE does not assign defined fill values and assigns a value of 0 for each instance a defined fill value is assigned in IDPS. |
PM_NPP_L1B_12047 | 2012-02-16 | 2012-02-16 | Pending | Bus Error outages IDPS / LPEATE Data problem that appears as missing granules in the Global browse images of the VIIRS product line for both IDPS and LPEATE. The difference between the two browse is the result of the granules not received at Land PEATE and not processed at IDPS as of yet. Additionally, differences between the reporting period of the data loss and what is observed in the browse images is due to the processing not completing for the day. Deficiency reports sent to SD3E for DOY's 037-039: no response. Deficiency reports to be sent to SD3E for DOY's 040-043. |
PM_NPP_L1B_11329 | 2011-11-29 | 2011-11-29 | Pending | Permanent data loss 2011/329/16:36:15 until 2011/330/19:37 There was a permanent data loss from VIIRS due to an onboard data anomaly for the period 2011/329/16:36:15 until 2011/330/19:37. This resulted in a complete data loss depicted by the missing data granules in the global browse images below. |
PM_NPP_L1B_11326a | 2011-11-23 | 2011-11-23 | Pending | VIIRS M-Band Reflectance, Bands 1-11 - Fill value (MISS_UINT16_FILL 65534) Data problem that appears as a data gap in VIIRS M-Band Reflectance, Bands 1-11, reports a MISS_UINT16_FILL 65534 fill value. This issue was observed on a granule passing over South America. The first image shows the granule of the reflectance RGB bands (M5,M4,M3), where the 65534 fill value is shown as the orange stripe. The purple stripes are fill values of ONBOARD_PT_UINT16_FILL 65533. The last two images show the corresponding granules of latitude and longitude geolocation data. Both the latitude and longitude granules do not show fill values. |
PM_NPP_VAFIP_22185 | 2022-07-05 | 2022-07-05 | Note | False Fire 2022.185 (07.04.22) VNP14 A false fire anomaly was observed on July 4th, DOY 2022.185 in the VNP14 product. The False fire occurred during a daytime orbit over the Atlantic Ocean. Granule 16:12 was found to contain false fire in the VNP14 product and anomalous high data values in the associated upstream L1B thermal M12 and M16 bands from the IDPS SDR in AS5000. The first image below shows the global browse image where false fire is observed in the Atlantic Ocean, highlighted by the orange box. The next image below shows the VNP14 fire product (left), with the associated M16 from IDPS SDR for granule 2022.185 16:12 from AS5000 (right). The false fire in VNP14 is associated with erroneously high value in M16 from AS5000. However, the same scan line is set to a fill value of 65534 in the M13 band of AS5200. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br><br><br> |
PM_NPP_L1B_22179 | 2022-06-28 | 2022-07-26 | Note | VIIRS SBC lock-up, 06.28.22 (2022.179) The VIIRS instrument experienced an anomaly on 06/28/2022 (2022.179) due to a VIIRS Single Board Computer (SBC) Lock-up. As a result, VIIRS science data output was impacted starting at 03:41Z. Engineering has been contacted and this issues is currently under investigation. All science and telemetry data will not be available until the instrument is restored to an operational state. All missed data will not be recoverable. Impacts to the NRT archive can be found<A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=331"> here.</A> <br><br>The operational data archive is currently impacted with missing L1B data in AS5000 from 03:30 - 06:42 (inclusive). During <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=466"> previous SBC lock-up events,</A> data recovery for the VIIRS instrument begins with the instrument configured to operate in Day mode. This seems to be the case for this event as granule 06:48 (the first data produced after the event) is a night time granule collected in Day mode. Users should be aware that while the instrument has started to reacquire data, the science quality has not been verified. VCST is currently looking into the calibration data to verify and define the impacted period for this event. This note will be updated as more information becomes available.<br><br><br><br><b><center>************************************************ <p style="color:red">VIIRS SBC lock-up: UPDATE 07.21.22</p> ************************************************</b></center><br><br> |
PM_NPP_L1B_22130 | 2022-05-10 | 2022-05-12 | Note | 2022.130 data loss On 2022.130 (05.10.22) SNPP experienced a small data loss for all instrument and HSK data. The data times for all instruments and HSK data were between 130/00:01:28z and 00:01:39z, with a few additional seconds of VIIRS data loss immediately after. The data loss occurred during the start of a night time orbit over the Arctic. This resulted in a <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=330"> non-recoverable data gap for SNPP VIIRS L1B data in NRT, with granule 00:00 not produced.</A> Operational processing was able to produce granule 00:00. However, granule 00:00 in AS5000 contained corrupt data values in the M13 band, which were not properly flagged. The NASA L1B data in AS5110 and AS5200 were produced correctly, without anomalous artifacts. The two images below show the data loss and anomalous values in the M13 thermal band (white stripe) for granule 00:00 in AS500, where the associated geolocation information was also impacted. The cause of this data loss is unknown.<br><br><br> |
PM_NPP_L1B_22075 | 2022-03-17 | 2022-03-17 | Note | data gap 03-16-2022 (2022.075) <br><br><br><b><center>************************************************ <p style="color:red">UPDATE: 03.21.22 </p> ************************************************</b></center><br><br><br> The L0 data has been successfully recovered and reprocessed for the event detailed below. The global browse images below show the fully recovered L1B data from AS5000 for both day and night time orbits. However, the downstream impacts on VNP14 persist and <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=357"> false fire is observed in granule 10:30 for VNP14 AS5000.</A> |
TM_NPP_VNP46_24267 | 2024-09-23 | 2024-09-23 | Note | DNB Sensor Zenith Valid Range Update <h1>DNB Sensor Zenith Valid Range Update</h1>The valid range minimum of "Sensor_Zenith" in the SNPP DNB daily (VNP46A1) and gap-filled (VNP46A2) products has been modified from "-90" to "0". The updated PGE554 with modified valid_min is currently operational as of September 19,2024 (2024/263). The prior mission period will not be reprocessed and users are requested to take note of the updated valid range. |
PM_NPP_VAFIP_22075 | 2022-03-17 | 2022-03-21 | Note | False Fire 2022.075 (03.16.22) VNP14 <br><br><br><b><center>************************************************ <p style="color:red">UPDATE: 03.21.22 </p> ************************************************</b></center><br><br> The L0 data has been successfully recovered and reprocessed for the event detailed below. However, the downstream impacts described persist and false fire is observed in granule 10:30 for VNP14 AS5000. Below are images showing granule 10:30 for the L1B and VNP14 active fire product. The white line in the L1B M13 band (left image) contains anomalously high values, and results in false fire for the associated downstream VNP14 granule (right image). Additionally, granule 10:30 was reviewed in the NASA L1B AS5200. The same scan lines that reported anomalous high values in AS5000, report fill values of 327679 for the M13 band of VNP02MOD in AS5200. Observations of False Fire should be contained to AS5000 and should not be present in the NASA L1B AS5200 downstream fire products.<br><br><br> |
PM_NPP_L1B_22010 | 2022-01-25 | 2022-01-25 | Note | 2022.010 data loss On 2022.010 (01.10.22) the SNPP VIIRS experienced a small data outage, which resulted in a non-recoverable data gap for SNPP VIIRS L1B data. The data loss occurred from 010/21:11:33z to 010/21:11:34z, impacting granule 21:06 in all Archive sets including AS5000, AS5110 and AS5200. This occurred during the start of a nighttime orbit over the Arctic and impacts the thermal bands in the night time portion of the granule. The two images below show the data gap in the M13 thermal band for granule 21:06, the geolocation information is not impacted. The cause of this data loss is unknown, and this data is not recoverable.<br><br><br> |
PM_NPP_L1B_21332 | 2021-12-01 | 2021-12-01 | Note | VIIRS timing errors 2021.332 (11.28.21) On 2021.332 (11.28.21) the SNPP and J1 VIIRS instruments experienced a timing error issue where a 1-second time jump was observed in the VIIRS geolocation information. Specifically, there was a 1-second backward jump a few seconds into the day, and it was corrected at 00:07:45. This affected both SNPP and JPSS-1 VIIRS instruments. The GPS receiver data in the ADCS packets for both missions were found to contain an extra record between 23:59:59 and 00:00:00, which jumps ahead a day and recorded invalid hour values. The cause of this data timing error is unknown.<br><br>The VIIRS geolocation team has concluded that geolocation errors extend from the start of the day 2021.322.0000 to 466 seconds (7 min 46 sec). Due to this impact to geolocation accuracy, the geolocation team recommended hiding L1B granules 2012.332.00:00 and 00:06 for both SNPP and J1. These granules will be hidden and the day will be re-processed in all of the forward processing SNPP and JPSS-1 archives.<br><br><br> |
PM_NPP_VAFIP_21234 | 2021-09-01 | 2022-10-17 | Note | False Fire 2021.234 (08.22.21) VNP14IMG, ROLLING NOTE A false fire anomaly was observed on August 22nd, DOY 2021.234 in the VNP14IMG product. The False fire occurred during a daytime orbit over Eastern Europe. Granule 09:54 was found to contain false fire in the VNP14IMG product and anomalous high data values in the associated upstream L1B thermal I4 band from the IDPS SDR in AS5000. The first image below shows the global browse image where false fire is observed (orange box). The next image below shows the VNP14IMG fire product (left), with the associated I4 band from IDPS SDR for granule 2021.234 09:54 from AS5000 (middle) and the same from NASA L1B in AS5200 (right). The false fire in VNP14IMG (Value of '8' observed in the #1 Zoom Image Window) is associated with erroneously high values (57175) in I4 from AS5000. However, the same scan line is set to a fill value of 65534 in the I4 band of AS5200. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br><br><br> |
PM_NPP_VAFIP_21220 | 2021-09-01 | 2022-10-17 | Note | False Fire 2021.220 (08.08.21) VNP14, ROLLING NOTE A false fire anomaly was observed on August 8th, DOY 2021.220 in the VNP14 product. The False fire occurred during a nighttime orbit over the Atlantic Ocean. Granule 04:42 was found to contain false fire in the VNP14 product and anomalous high data values in the associated upstream L1B thermal M13 band from the IDPS SDR in AS5000. The first image below shows the global browse image where false fire is observed in the Atlantic Ocean. The next image below shows the VNP14 fire product (left), with the associated M13 from IDPS SDR for granule 2021.220 04:42 from AS5000 (middle) and the same from NASA L1B in AS5200 (right). The false fire in VNP14 (Value of '9' observed in the #1 Zoom Image Window) is associated with erroneously high values (628) in M13 from AS5000. However, the same scan line is set to a fill value of 327679 in the M13 band of AS5200. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br><br><br> |
PM_NPP_VAFIP_21225 | 2021-09-01 | 2021-09-01 | Note | False Fire 2021.225 (08.13.21) VNP14IMG A false fire anomaly was observed on August 13th, DOY 2021.225 in the VNP14IMG product. The False fire occurred during a daytime orbit over Northern Russia. Granule 04:24 was found to contain false fire in the VNP14IMG product and anomalous high data values in the associated upstream L1B thermal I4 band from the IDPS SDR in AS5000. The first image below shows the global browse image where false fire is observed (orange box). The next image below shows the VNP14IMG fire product (left), with the associated I4 band from IDPS SDR for granule 2021.225 04:24 from AS5000 (middle) and the same from NASA L1B in AS5200 (right). The false fire in VNP14IMG (Value of '8' observed in the #1 Zoom Image Window) is associated with erroneously high values (57398) in I4 from AS5000. However, the same scan line is set to a fill value of 65534 in the I4 band of AS5200. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br><br><br> |
PM_NPP_VAFIP_21233 | 2021-08-25 | 2021-10-01 | Closed | False Fire 2021.233 (08.21.21) / 2021.228(08.16.21) VNP14 <br><br><br><b><center>************************************************ <p style="color:red">UPDATE: 10.01.21 </p> The L0 data has been successfully recovered and reprocessed for the two events detailed below. The downstream impacts described below have been fully resolved, and this issue has been closed.<br><br>************************************************</b></center><br><br><br><br><br><br><br><br>During the month of August, 2021 there were two dates 2021.233 (08.21.21) / 2021.228(08.16.21) where periods of VIIRS scans were found to be missing significant numbers of packets. This resulted in corrupt L1B data, anomalous values in the M13 band and false fire in the downstream VNP14 product. For the two events detailed below, L0 data is currently being recovered from the back-up system and will be reprocessed for all the impacted periods. <br><br><br><b><center>************************************************ <p style="color:red">False Fire 2021.233 (08.21.21) VNP14 </p> ************************************************</b></center><br><br>A false fire anomaly was observed on August 21st, DOY 2021.233. The False fire occurred during a day time orbit over Russia. Granule 03:36 was found to contain false fire in the VNP14 product and anomalous high data values in the associated upstream L1B thermal M13 band from the IDPS SDR in AS5000. The image below shows the VNP14 fire product (left), with the associated M13 from IDPS SDR for granule 2021.233 03:36 from AS5000 (middle) and the same from NASA L1B in AS5200 (right). The false fire in VNP14 is associated with erroneously high values in M13 from AS5000. However, the same scan line is set to a fill value of 327679 in the M13 band of AS5200. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br><br><br> |
PM_NPP_L1B_21228 | 2021-08-16 | 2021-08-16 | Note | Geolocation accuracy of the recently released C2 S-NPP and C2.1 J1 L1 products During certain spacecraft maneuver periods, data users may notice occasional errors in the geolocation accuracy of the recently released C2 S-NPP and C2.1 J1 L1 products. These erroneous periods/granules will soon be cleaned up and fixed. In the meantime, for a detailed record of the different S-NPP and J1 maneuvers, data users can reference the LDOPE maneuver records<A href="https://landweb.modaps.eosdis.nasa.gov/maneuver?sensor=VIIRS&sat=SNPP"> here.</A> <br><br> |
PM_NPP_VAFIP_21216 | 2021-08-12 | 2021-08-17 | Note | Impacts of Safe mode on VNP14IMG 2021.216-217 (08.04-05.21) On August 3, 2021.215 S-NPP lost nominal mission pointing status and all instruments were put into a safe mode, which <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=469"> directly impacted the L1B VIIRS instrument data collection</A> and all associated downstream products. The VIIRS Data recovery started on Aug 4, 2021.216. Impacts to I-5 L1B thermal band were observed, which directly effects the downstream VNP14IMG product. While no false fire were observed during this period, fire retrievals in the VNP14IMG were significantly limited in the daytime VNP14IMG product for days 2021.216 and 217.<br><br>Starting on 2021.216.1836 the L1B I-5 band began to retrive data however, the associated Quality Flag reports poor quality up until 2021.217.08:00. Due to this, the VNP14IMG fire product reports fill values of "0" (not-processed) in all daytime granules, and only retrieves fire values during night time orbits and day/night ("both") boundary granules from 2021.216.1836 through 2021.217.08:00. The global browse images below show the day time and night time 2021.216 and 2021.217 VNP14IMG products. |
PM_NPP_L1B_21217 | 2021-08-09 | 2021-08-09 | Note | 2021.217 data loss On 2021.217 (08.05.21) the SNPP VIIRS experienced a small 58 second data outage, which resulted in a non-recoverable data gap for SNPP VIIRS L1B data. The data loss occurred from 217/03:19:00z to 217/03:19:58z, impacting granule 03:18 in all Archive sets including AS5000, AS5110 and AS5200. This occurred during a daytime orbit over the middle of the Pacific Ocean and no significant impacts to land products are expected. The two images below show the data gap in the geolocation information and M13 thermal band for granule 03:18. The cause of this data loss is unknown, and this data is not recoverable.<br><br><br> |
TM_NPP_L1B_24248 | 2024-09-04 | 2024-09-04 | Note | SNPP Downlink 2024/243 Data Gap <h1>SNPP Downlink 2024/243 Data Gap</h1>On August 30, 2024 (2024/243), the SNPP suffered an unrecoverable data gap from 19:58:21 - 19:59:46 due to a lost downlink. The data loss impacted DOY 2024/243 granule 19:54. |
PM_NPP_L1B_21215 | 2021-08-03 | 2021-08-18 | Note | S-NPP spacecraft is in safe mode and all science data acquisition disabled since 12:46 UTC, August 3 2021 Users of S-NPP land data products from NASA NRT LANCE and Land SIPS are requested to note that the S-NPP lost its nominal mission pointing status on August 3, 2021 and all instruments have been put in a safe mode. No science data will be available to the users, starting from 12:46 UTC on August 3, 2021. The spacecraft mission team is working to restore the spacecraft to nominal status and we will update this note when the recovery is fully complete and science data collection is resumed.<br><br><br><b><center>************************************************ <p style="color:red">UPDATE 08.04.21 </p> ************************************************</b></center><br>S-NPP mission engineering team was able to successfully return the S-NPP spacecraft back to the nominal Mission pointing status at 22:28 UTC (Aug 3, 2021). The instrument recovery efforts commenced at 14:07 UTC Aug 4, 2021. As of 14:17 UTC, ATMS, CERES, and OMPS instruments were recovered. The science data distribution will commence only after all the instruments have been recovered and all instrument operations have been found to be nominal by the respective Cal/Val teams. It is anticipated that by 22:00 UTC Aug 4, that instrument recovery on SNPP should be completed.<br><br><br><b><center>************************************************ <p style="color:red">UPDATE2 08.04.21 </p> ************************************************</b></center><br>As of 1600 UTC the VIIRS instrument was recovered. Please note that VIIRS instrument tuning and product quality checks will take at least 2 days.<br><br><br><b><center>************************************************ <p style="color:red">UPDATE 08.05.21 </p> ************************************************</b></center><br>NASA LANCE NRT and Land SIPS has started generating the S-NPP VIIRS products, post VIIRS recovery on 1600 UTC August 4. However, several of the onboard VIIRS instrumentation is still under QA by the Cal/Val team and especially the cold focal plane temperature (CFPA) affecting the LWIR/SW-MWIR bands may not have reached the optimal temperature yet, following this VIIRS recovery. A final update from the Cal/Val team is expected soon, confirming the final status of the VIIRS instrumentation and the products. Till then, users are urged to maintain caution while using these data.<br><br><br><b><center>************************************************ <p style="color:red">UPDATE 08.06.21 </p> ************************************************</b></center><br>Please note that all S-NPP VIIRS instruments are approaching their nominal status as of 1230 UTC on August 5, 2021, following the VIIRS recovery at 1600 UTC on August 4. The VIIRS Calibration Support Team (VCST) has now evaluated all the VIIRS instruments and have confirmed that all the instruments are either nominal or are approaching their nominal status, as summarized below:<br><br> 1. TEB Bands - The Cold Focal Plane Temperature approached the nominal temperature of ~80K at 10:15 UTC on August 5 and most TEB band F-factors have been found to be almost nominal since then.<br><br> 2. VisNIR - The VisNIR bands F-factor values are also approaching gradually their pre-safe mode values and should be mostly nominal now with the exception of the SWIR bands. But the SWIR bands F-factors are expected to become nominal within a few days.<br><br> 3. DNB Band - Discontinuities have been observed in DNB F-factors and DN0 (e.g. HGS) as well. They are expected to be back to nominal values but may take a few days.<br><br>For more detailed findings from the VCST team, please refer to these slides <a href="https://landweb.modaps.eosdis.nasa.gov/data/userguide/SNPP_VIIRS_Safe_Mode_Recovery_Preliminary_update_2_JX.pptx">here</a>. For more details on the impact to the downstream VNP14 fire products, please check <a href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=352">here</a> |
PM_NPP_L1B_21134 | 2021-05-17 | 2021-05-17 | Note | 2021.134 data loss On 2020.134 (05.14.21) the SNPP VIIRS experienced a small data outage, which resulted in a non-recoverable data gap for SNPP VIIRS L1B data. The data loss occurred from 134/10:59:48z to 134/11:03:43z, impacting granule 11:00 in all Archive sets including AS5000, AS5110 and AS5200. Granule 11:00 was not produced in archive set 5000 due to the failure of the geolocation code, but was produced with gaps in the reflectance, thermal and geolocation layers in Archive Sets 5110 and 5200.<br><br>While most of the gaps observed in granule 11:00 of AS5110 and AS5200 contain appropriate fill vales, a few scans contain anomalous pixel values, which are within range of the data layers in the reflectance and thermal bands. However, the scan quality flag layer associated with the gaps are flagged appropriately, and data users should reference these flags when using this impacted granule 11:00. The first two images below show the data gap in the geolocation information and M13 thermal band for granule 1100, where this data loss occurred in AS5110. The last image shows the AS5000 global browse image for day 2021.134, where the missing granule 11:00 is observed over African and the Arabian peninsula. The cause of this data loss is unknown, and this data is not recoverable.<br><br><br> |
PM_NPP_FPAR_21005 | 2021-01-05 | 2021-02-10 | Closed | Missing tiles VNP15A1H/A2H <br><br>**** Update: 02.10.21, The 8 missing tiles have been regenerated for this period.**** <br><br>Due to an issue during production the S-NPP C1 VNP15A1H/A2H products were found to be missing 8 tiles (h31v13, h00v10, h01v11, h06v03, h09v02, h26v02, h29v03, h35v10). The missing tiles occur from the start of the mission to DOY 2020.345. In early January of 2021, the VNP15A1H/A2H will be reprocessed for S-NPP C1 from the beginning of S-NPP mission (2012-01-19) and this note will be updated accordingly. The first image below show a spatial subset of the global browse image for VNP15A2H FPAR from data day 2020.329, where tile H09v02 is missing over Alaska. The second image shows data day 2020.345, where tile H09v02 has been retrieved in C1 forward production, starting on day 2020.345.<br><br><br> |
PM_NPP_L1B_20218 | 2020-08-07 | 2020-08-07 | Note | data loss due to CBU transition 08-05-2020 (2020.218) On 2020218 (08/05/2020) a C3S Transition from CBU to NSOF caused a data delay of SNPP VIIRS, which resulted in <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=327"> a data loss for granule 16:12 in NRT.</A> The data was eventually recovered in the forward processing however, granule 16:12 was impacted with approximately 30s of degraded data from SNPP @16:14Z. Granule 16:12 was reviewed, quality flag and fill values were found to be properly assigned to all the impacted bands, including the associated geolocation. This data loss occurs over the arctic during a daytime orbit. Below the images show the RGB reflectance image and the associated geolocation information. <br><br><br> |
PM_NPP_L1B_20212 | 2020-07-30 | 2024-06-29 | Note | S-NPP VIIRS instrument Petulant Mode/SBC Lockup Events <h1>S-NPP VIIRS instrument Petulant Mode/SBC Lockup Events</h1>On occasion the SNPP VIIRS instrument experiences an anomaly due to a VIIRS Single Board Computer (SBC) Lock-up. As a result, VIIRS science data output has been found to be directly impacted during these events (<A href="https://landweb.modaps.eosdis.nasa.gov/cgi-bin/NPP_QA/displayCase.cgi?esdt=NPP_L1B&caseNum=PM_NPP_L1B_19021&caseLocation=cases_data">01.21.19 (2019.021), </A> <A href="https://landweb.modaps.eosdis.nasa.gov/cgi-bin/NPP_QA/displayCase.cgi?esdt=NPP_L1B&caseNum=PM_NPP_L1B_17239&caseLocation=cases_data">08.27.17 (2017.239), </A><A href="https://landweb.modaps.eosdis.nasa.gov/cgi-bin/NPP_QA/displayCase.cgi?esdt=NPP_L1B&caseNum=PM_NPP_L1B_16355&caseLocation=cases_data">12.20.16 (2016.355), </A><A href="https://landweb.modaps.eosdis.nasa.gov/cgi-bin/NPP_QA/displayCase.cgi?esdt=NPP_L1B&caseNum=PM_NPP_L1B_16226&caseLocation=cases_data">08.13.16 (2016.226), </A><A href="https://landweb.modaps.eosdis.nasa.gov/cgi-bin/NPP_QA/displayCase.cgi?esdt=NPP_L1B&caseNum=PM_NPP_L1B_14282&caseLocation=cases_data">10.09.14 (2014.282) </A>). In some instances, the VIIRS instrument can operate in Day mode for periods of multiple day and night orbits, impacting day/ night flag assignments in L1B data. During which, multiple L1B DNB granules are found to be corrupt for these periods. LandSIPS has previously identified and removed these corrupt L1B granules from production that were either affected by data outage or were observed to negatively impact downstream L2 land products. However, most of the DNB daytime reflectance and downstream dependent products (the SIN DNB BRDF/Albdeo - VNP43DNBA* and the DNB NTL - VNP46A2 ) are being recently developed and were produced after the initial QA review. Therefore, additional granules impacting the DNB reflectance have not been removed for these products.<br><br> During the most recent review, additional artifacts have been identified in the DNB daytime reflectance granules for these lockup events, which include new granules previously unaccounted for by the original LandSIPS review. This has led to the removal of these additional granules, specifically for the processing of the downstream L3 DNB products like the VNP43DNBA1/A2/A3/A4 and the DNB NTL (VNP46A2). However, some of these DNB L3 day and night products like the DNB BRDF and the DNB NTL had already been produced prior to the discovery of these additional artifacts. So, users are urged to maintain caution while using these products and check against such SBC event days that are listed below.<br><br>The first examples below shows the impact of this event on the daytime DNB reflectance (VNP39) for day A2012050 (2012-02-19). Additionally, the second global browse image of the daily DNB L2G lite reflectance (VNPLG39GA) that is used as input to the VNP43DNBA* suite of products, show the impacts of the corrupt data on the downstream products where these granules have not been removed from the archive. Additionally, L1B granule examples from AS5000 and 5110 are provided, which show the artifacts observed at the granule level during these events. The last example image shows a recent production date of VNP39, where corrupt granules are observed during daytime orbits over North America and the Pacific Ocean.<br><br><br> |
PM_NPP_L1B_20189 | 2020-07-08 | 2020-07-08 | Note | Data quality impacts during maneuver periods For LandSIPS S-NPP C1 processing, the L1B data are reviewed in detail during and surrounding the time periods for all maneuver events. This process helps identify corrupt granules, which may negatively impact overal quality of L1B data and downstream data products. During the data quality review process, any reflectance, geolocation or thermal layers found to contain anomalous or corrupt data values are flagged and are recommended to be hidden or removed from production. However, in a few instances, granules flagged to be removed have not been removed from production and are found to be included as input to downstream products. This results in possible quality impacts to downstream data products. Users should be aware that some corrupt granules may have inadvertently been included in downstream products. In these instances, users should reference <A href="https://landweb.modaps.eosdis.nasa.gov/maneuver?sensor=VIIRS&sat=SNPP">the maneuver charts</A> for detailed information on dates, time periods and granules, which may be directly impacted. The example below details one instance where a corrupt granule during a maneuver period was identified for removal, but was unintentionally included in the L1B and downstream reflectance product. A similar issue currently affects <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=291">C2 J1 products in AS 5200</A>.<br><br><br>S-NPP VIIRS Lunar Calibration Roll Maneuver<br>02/05/20 (2020036), granule 09:00 and 09:06 - Corrupt Reflectance and BT data for AS5000<br><br>This image shows the downstream surface reflectance product VNP09 for granule 2020.036.0900. This granule was flagged to be removed in the L1B data due to anomalous data values in the M5 reflectance band. A portion of this granule is corrupt and is shown in the zoom window as a horizontal stripe running across the granule. Within this stripe, anomalous values in the M5 band are highlighted in red. |
PM_NPP_L1B_20170 | 2020-06-25 | 2020-06-25 | Note | 2020.170 data loss On 2020.170 (06.18.20) the SNPP VIIRS experienced a small data outage, which resulted in a non-recoverable data gap for SNPP VIIRS L1B data. The data loss occurred from 15:29:48 to 15:30:06, impacting granules 15:24 and 15:30 in both AS5110 and AS5000. This occurred during the end of a nighttime orbit over Antarctica. The images below show the data gap in the geolocation information and M13 thermal band where this data loss occurred in AS5000. The cause of this data loss is unknown, and this data is not recoverable.<br><br><br> |
PM_NPP_L1B_20142 | 2020-05-15 | 2021-09-02 | Note | Science data loss due to DAS upload commands The SNPP VIIRS instrument experiences routine data gap outages due to DAS (Detailed Activity Schedule) upload command events. This specific type of data loss event occurs monthly and can last between 18 and 23 seconds. The impacted granule is observed with a slight shift in continuity of the values within each L1B layer, including reflectance, thermal and geolocation. No fill values in the L1B are associated with these events. The images below shows an example of this data loss in the geolocation information and reflectance bands where this event occurred. This data is not recoverable, and the historical occurrences of these events are currently under investigation.<br><br> The examples below show the event which occurred on 2020.142 (05.21.20): 1452:15 - 1452:34, (19 seconds): |
PM_NPP_BRDF_20113 | 2020-04-22 | 2020-04-22 | Pending | Impacts of High Aerosol Retrieval on VNP43 The abnormally high activation of the high aerosol flag in the Collection 1 (C1) VNP09 product </A>, has impacted downstream products. The VNP43 BRDF/Albedo/NBAR product (VNP43) is affected by reducing the number of otherwise acceptable observations used as input to characterize surface anisotropy. This effect (most obvious over arid bright surfaces)</A>, results in a reduced number of high quality full BRDF model inversions. Therefore, users should be aware that bright arid surfaces (normally associated with high quality BRDF/Albedo/NBAR retrievals) are likely to be somewhat represented by lower quality results in C1. VNP09 has been corrected for Collection 2 (C2). Therefore, users should avoid substantive use of C1 VNP43 over arid regions (and wait for C2 products). In any event, users are <b>always strongly encouraged</b> to download and use the extensive QA data provided in VNP43M/IA2, in addition to the briefer mandatory QA provided as part of the VNP43M/IA1, 3 and 4 products.<br><br> |
PM_NPP_L1B_20109 | 2020-04-21 | 2020-04-21 | Note | 2020.109 data loss due to contact error On 2020.109 (04.18.20) the SNPP spacecraft experienced telemetry errors in the downlink which resulted in a non-recoverable data gap for SNPP VIIRS. The data loss lasted nearly a minute from 12:44:24 to 12:45:25, impacting granule 12:42 during the end of a daytime orbit over Antarctica. The images below show the data gap in the geolocation information and M13 thermal band where this data loss occurred. This data is not recoverable. |
TM_NPP_VNP64_24247 | 2024-09-03 | 2024-09-03 | Note | Burned Area Early Mission Degradation <h1>Burned Area Early Mission Degradation</h1>The C2/SNPP VIIRS monthly burned area product (VNP64A1) for the first month of 2012 (2012/032) will not be distributed and removed from the archive. The extensive quality assessment of the product revealed significant degradation in the data due to incomplete SNPP VIIRS data record during the early days of the mission. |
PM_NPP_CM_20101 | 2020-04-10 | 2020-04-14 | Note | Blocky artifacts in C1 Cloud Mask impact downstream products The VIIRS S-NPP Collection 1 (C1) land cloud mask intermediate product (VNP35_L2) contains blocky artifacts, that are verified to be resulting from use of coarse resolution (5km) Vegetation Index (VI) seed files used as input to the cloud mask process. These artifacts have propagated downstream, resulting in similar artifacts in the downstream science products. Offline tests of the C2 cloud mask process that use the VI seed file at 1km native resolution have been confirmed to fix this issue. In addition, the C2 cloud mask has minor improvements for checking of snow-sea-ice along the coastlines, which would also fix occasional commission errors along the coastlines. |
PM_NPP_VAFIP_20025 | 2020-01-27 | 2020-01-27 | Note | False Fire 2020.025 VNP14IMG A false fire anomaly was observed on January 25th, DOY 2020.025 in both the LANCE Near Real Time (NRT) archive set 5000 VNP14IMG_NRT, and in the forward processing land SIPS science VNP14IMG from archive 5000. The False fire occurred during a day time orbit over Eastern Europe. Granule 09:36 was found to contain false fire in both the NRT VNP14IMG_NRT and forward processing AS5000 VNP14IMG product. The cause of this false fire is related to the anomalous high data values in the associated upstream L1B thermal I5 band. The first image below shows an example of the false fire in the NRT processing. In the second image, the false fire in the forward processing land SIPS VNP14IMG product is observed in association with the anomalous high data value in the L1B I5 band.<br><br>Note that processing of the same product using the NASA L1B (VNP02IMG) is not expected to produce any such false fire because the same scan lines in the NASA L1B (in AS 5110 of LAADS) records a fill value of 65532 with a QA flag of 512 - both meaning missing earth view observation. <br><br><br><br> |
PM_NPP_L1B_20024 | 2020-01-24 | 2020-01-24 | Note | NRT SNPP VIIRS Data Gaps (Rolling List) This rolling post will document the known instances where data gaps occur for SNPP VIIRS Near Ral Time (NRT) processing stream. For the majority of these cases a ground station anomaly or contact error event has occurred, which delays the L0 data. This delay results in a data gap when the NRT processing stream window closes for the day. However, the Land SIPS science data in the forward processing is not impacted by these delays as the L0 data from the satellite is eventually recovered. Below is a record of the events that directly impact NRT, Images will be provided when available.<br><br><br><br> - 2020.023: VIIRS SNPP NRT processing data loss on 2020.023 (01.23.20). SNPP Data Delay observed between 11:36 and 1200Z. This delay appears to have been caused by a ground station anomaly. Processing in the NRT stream has closed, resulting in a gap in the VIIRS L1B AS5001 between 11:18 and 11:48. This impacts the NRT processing only and does not impact LandSIPS forward production for SNPP. This data gap occurred during a daytime orbit over Africa. <br> |
PM_NPP_L1B_20017 | 2020-01-17 | 2020-01-21 | Note | SNPP and NOAA-20 are currently affected by a calibration anomaly 01.16 2020 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. NOAA has stated that 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.<br><br>However, any direct impact of this on the NASA LandSIPS L1B calibration will be minimal as the calibration of L1B radiance products in LandSIPS is not dependent on the solar vector. The impact on the L1B reflectance products should also be small of around 0.1%, mainly coming from errors in the Earth-Sun distance. The NASA LandSIPS downstream land products will be impacted however, through any impact on the cloud mask and from inaccurate day/night delineation and compositing of values in L3 downstream products, based on the high sun angle. This issue will also directly impact the active fire products, <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=350"> where false fires have been observed.</A><br><br><br>***** NOTE 01.21.20 *****<br>A corrected LUT, containing the fix for the planetary ephemeris LUT, was delivered by VCST and was put in place for NRT processing from 01/18/2020 processing from:<br>2020.017.2218 - AS 5001 - S-NPP<br>2020.017.2218 - AS 5000 - S-NPP<br>2020.018.1236 - AS 5200 J1/N20.<br>All L1/L2 and downstream products are now considered to be nominal.<br><br>LandSIPS Forward Processing:<br>Additionally, the corrected LUT containing the fix for the planetary ephemeris LUT, was put in place for Land SIPS Forward Processing from 01/17/2020 (S-NPP: AS 5000/AS 5110) and from 01/18/2020 (J1: AS 5200). The exact timings, when the corrected L1B LUT was put into place are <br>J1 AS 5200: 2020.018.0948<br>S-NPP AS 5110: 2020.017.1112<br>S-NPP AS 5000: 2020.017.1000.<br>Hence, all data from forward processing will be nominal from day 01/18/2020 for C1 S-NPP (AS 5000, AS 5110) and from day 01/19/2020 for C2 J1 (AS 5200). This note will be updated when the reprocessing has occurred. <br><br><br><br><br><br><br><br><br><br>The global browse example images below from the Near Real Time processing stream show the initial downstream impacts to the L2 Surface Reflectance product, Snow product, and Ice Surface Temperature that are expected during this calibration anomaly period. In the examples below DOY 2020.015 is shown on the left for comparison prior to the calibration anomaly. The images on the right, show how the downstream products are impacted, specifically effect on day/night delineation in the high latitudes.<br> |
PM_NPP_BRDF_20015 | 2020-01-16 | 2020-01-16 | Pending | DNB BRDF/Albedo suite of product reprocessing 2012 The tiled and CMG version of the DNB BRDF/Albedo suite of products (VNP43DNBA1/A2/A3/A4 and VNP43C*/VNP43D*) from the current S-NPP C1 processing will be re-processed for the year 2012, starting from day 02/10/2012. This will be done to remove errors that are seen in these products, caused by some artifacts in the upstream DNB L1B over four days in 2012: 2012049, 2012050, 2012088 and 2012327. The artifacts seen in DNB L1B, affects both the day and night time observations and thus impacts the downstream DNB reflectance and the DNB BRDF/Albedo products. Given the dependency of the BRDF estimation for any day, over prior days through the use of a BRDF archetype database, LandSIPS has decided to re-process most of 2012 on and after 02/10/2012.The four images below show the L1B DNB and downstream products where the artifacts are observed on 2012.050 during both daytime and night time orbits.<br>***NOTE*** The VNP39 and VNPLG39GAC are intermediate products and are not distributed to users. <br><br> |
PM_NPP_VAFIP_20016 | 2020-01-16 | 2020-01-21 | Note | False Fire 2020.016 VNP14IMG Due to calibration anomaly A false fire anomaly was observed on January 16th, DOY 2020.016 from the LANCE Near Real Time (NRT) archive set 5000, VNP14IMG_NRT. The False fire occurred during a day time orbit over the North Eastern coast of Australia, within the town of Townsville and along the Burdekin River. The NRT VNP14IMG_NRT granule 03:36 was found to contain false fire in the VNP14IMG product. The cause of this false fire is currently under investigation and is related to the <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=460"> SNPP and NOAA-20 a calibration anomaly 01.16 2020</A> directly impacting solar vector calculations of all SNPP and N20 NRT and forward processing archives. Below are two images showing the false fire. The first image shows the RGB VNP09 reflectance NRT data in World View, where the VNP14IMG_NRT false fire is ovar laid. The second image shows the VNP 14IMG_NRT granule 03:36 for this data day 2020016, where the false fires can be observed over the town and along the river. This note will be updated as more information becomes available.<br><br>***** NOTE *****<br>A corrected LUT, containing the fix for the planetary ephemeris LUT, was delivered by VCST and was put in place for NRT and standard forward processing streams from 01/18/2020 and in standard processing from<br>2020.017.2218 - AS 5001 - S-NPP<br>2020.017.2218 - AS 5000 - S-NPP<br>2020.018.1236 - AS 5200 J1/N20.<br><br>All L1/L2 and downstream products are now considered to be nominal.<br>The impacted NRT data will NOT be reprocessed and users should avoid using the NRT L1B and downstream products including the Fire Data from 2020.016/017.<br><br><br><br> |
PM_NPP_L1B_20008 | 2020-01-10 | 2020-01-10 | Note | S-NPP VIIRS Flight Software (FSW) Upload 2020.008 On January 08, 2020 (2020.008), a planned S-NPP VIIRS Flight Software (FSW) Upload </A> was performed during times 13:28:38Z to 20:22:31Z. During this time period impacts to data were expected in the L1B reflectance / thermal, geolocation and DNB data. Review of L1B data confirmed multiple granules were impacted with corrupt data or found to contain the incorrect Day night flag assignments. The three images below show the overall data impacts from the FSW activity, which resulted in the data impacts listed below:<br><br>- 15:06 - 15:54: All L1B contain incorrect Day Night flags (instrument operating in Day mode during a night orbit)<br>- 15:18, 15:30, 15:42, 16:48, 16:54: Corrupt geolocation, or artifacts in the L1B reflectance and Thermal bands.<br>- 16:00 - 20:06: compromised / corrupt DNB bands for both day and night.<br><br><br> |
PM_NPP_VAFIP_20001 | 2020-01-09 | 2020-01-09 | Note | False Fire 2020.001 A false fire anomaly was observed on January 1st, DOY 2020.001. The False fire occurred during a day time orbit over Russia. Granule 02:00 was found to contain false fire in the VNP14IMG product and anomalous high data values in the associated upstream L1B thermal I5 band. The first two images below shows the false fire in VNP14IMG fire product and the associated I5 L1B data for granule 2020.001 02:00 from AS5000. While the I5 band and VNP14IMG granule 02:00 are impacted in AS5000, The L1B in AS5110 is also impacted during this period. The third image below shows the I5 L1B data for granule 2020.001 02:00 from AS5110 where the anomalous is also observed.<br><br> |
PM_NPP_VAFIP_20007 | 2020-01-09 | 2020-01-09 | Note | False Fire 2020.007 VNP14 A false fire anomaly was observed on January 7th, DOY 2020.007. The False fire occurred during a day time orbit over Europe. Granule 13:30 was found to contain false fire in the VNP14 product and anomalous high data values in the associated upstream L1B thermal M13 band from the IDPS SDR in AS 5000. The first two images below shows the false fire in VNP14 fire product and the associated M13 from IDPS SDR for granule 2020.007 13:30 in AS5000. The third image shows the VNP14 fire product (left), with the associated M13 from IDPS SDR for granule 2020.007 13:30 from AS5000 (middle) and the same from NASA L1B in AS5110 (right). The false fire in VNP14 is associated with erroneously high values in M13 from AS5000 but the same is set to a fill value of 65532 in the M13 band of AS5110. Thus, such instances of false fires are expected to go away when the LandSIPS active fire code starts using the NASA L1B.<br><br> |
PM_NPP_BRDF_19347a | 2019-12-13 | 2020-01-21 | Closed | VNP43DNB processing error An error was discovered in the loader module of the LandSIPS process that generates the S-NPP DNB BRDF products (VNP43DNBA1/A2/A3 and A4), leading to staging of incomplete input daily DNB reflectance tiles for this process. Hence, the different VNP43DNBA1/A2/A3 and A4 products may not reflect the full suite of gridded tile inputs for different data days, within the affected period, 2012.359 (12/24/2012) to 2013150 (04/20/2013). All the S-NPP VIIRS LandSIPS products (VNP43DNBA1/A2/A3 and A4) from AS 5000 will need to be re-processed for this affected period. Below is an example of the impacted period where this error occurred. <br><br>LandSIPS has made the necessary fix in the loader module and a re-processing of the affected days is completed, this period has been reprocessed and corrected.<br><br> |
TM_NPP_L1B_24212 | 2024-07-30 | 2024-07-31 | Note | SNPP VIIRS - Bus Anomaly <h1>SNPP VIIRS - Bus Anomaly</h1>On 7/29/2024, the SNPP VIIRS 1394 bus alarms occurred at 09:58:20z impacting data quality. The 1394 reset is planned soon and further updates will be provided when available. The SNPP VIIRS NRT processing will be put on hold until the issue is resolved.<br><h2 style="text-align:center;">*** UPDATE 07/31/2024***</h2><br>The SNPP VIIRS 1394 bus alarm reset occurred as a result of the <a href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=716">Command Data Processor (CDP) Anomaly event </a> on 07/24/2024. The Geolocation and calibration teams have evaluated the data staged in test achieve set and have approved the data for operational use. Please see below the SNPP VIIRS Ground Control Point (GCP) residual plots between 07/24/2024 - 07/30/2024. |
PM_NPP_BRDF_19347 | 2019-12-13 | 2019-12-13 | Pending | VNP43C/D processing error An error was discovered in the loader module of the LandSIPS process that generates the S-NPP BRDF/Albedo CMG suite of products (VNP43C*/D*) leading to staging of incomplete inputs for this process. Hence, the different VNP43C*/D* products may not reflect the full suite of gridded tile inputs for different data days within the affected period, from 07/19/2012 - 12/04/19. All the S-NPP VIIRS LandSIPS VNP43 CMG products (VNP43C1/C2/C3/C4 and the VNP43D* suite) from AS 5000 will need to be re-processed for this affected period. LandSIPS has made the necessary fix in the loader module and a re-processing of the affected days is expected to start soon.Below is an example of the impacted period where this error occurred.<br><br> |
PM_NPP_L1B_19304 | 2019-10-31 | 2019-11-26 | Note | Data loss on day 2019304 due Anomaly On October 31, 2019 (2019.304), SNPP VIIRS experienced an anomaly causing a data loss from roughly 03:48 through 07:42. Data from VIIRS resumed at roughly 06:38, however, there were a number of instrument configuration activities that caused gaps and data issues resulting in no output data through 07:42 and potential small gaps in the granules covering from 08:10 through 08:24. Review of L1B data confirmed multiple granules were impacted with corrupt data or found to contain the incorrect Daynight flag assignment. The granules listed below were provided to production to be removed / hidden form the collection. Additionally, the two images below show the overall data loss from the anomaly. First, the L1B reflectance global browse image for daytime orbits and the brightness temperature band M16 band for the nighttime orbits.<br><br>Impacted granules from 2019304 anomaly:<br>03:48 :corrupt data<br>06:36 :corrupt data<br>07:48 :corrupt data<br>07:54 :corrupt I5<br>08:00 :corrupt I5<br>08:06 :corrupt I5<br>08:12 :corrupt data<br>08:18 :corrupt data<br>08:24 to 09:06 :Night Granules incorrectly flagged as (day)<br>09:54 :(both) granule incorrectly flagged as (day)<br>10:00 to 10:42 :missed orbit of granules to remove. Night Granules incorrectly flagged as (day)<br>10:48 :(both) granule incorrectly flagged as (day)<br>11:36 :(both) granule incorrectly flagged as (day)<br>11:42 to 12:18 :Night Granules incorrectly flagged as (day)<br>12:24 :(both) granule incorrectly flagged as (day)<br>13:18 :(both) granule incorrectly flagged as (day)<br>13:24 to 14:00 :Night Granules incorrectly flagged as (day)<br>14:06 :(both) granule incorrectly flagged as (day)<br>14:54 :corrupt geolocation<br><br><br>******** UPDATE 11.26.19 ********<br><br>During production, the majority of granules from between 03:54 through 07:42 have failed to process successfully in the first step of the production chain. Additionally, granules impacted by this outage have been further organized into separate stages of outages. Due to production failure, granules within these outages have been removed from production and will not be used for L1B and downstream products.<br><br> - first outage 03:48 through 09:06 granules<br> - second outage 09:54 through 10:48 granules<br> - third outage 11:36 through 12:24 granules<br> - fourth outage 13:18 through 14:06 granules <br> - last outage 14:54 granule.<br><br><br> |
PM_NPP_L1B_19278 | 2019-10-07 | 2019-10-07 | Pending | Scan Sync Loss artifact AS5000 2019.278 (10.05.19) On 2019.278 (10/05/2019).The VIIRS instrument experienced a telescope Sync Error #106 Time: 10/05/2019, 20:48:25 - 20:50:04z. This was a "Long" duration type event. The data loss was observed during the start of a daytime orbit over the Antarctic. The Reflectance, BT bands, and geolocation layers were reviewed. Granule 20:48 was found to contain a data loss in the geolocation, reflectance and BT bands. The examples below show the L1 geolocation and BT band M13 for granule 20:48 in Archive Set 5000 and 5110. During this scan sync data loss an artifact of low data values was observed in AS 5000 reflectance and BT bands and can be seen in the second image as a thin line of anomalous values just below the sync loss event. However, no artifacts were observed in the same NASA L1B granule, Archive Set 5110. This issue is currently under investigation and information will be posted when details become available as to the cause of these anomalous data values.<br><br> |
PM_NPP_VAFIP_19261 | 2019-09-20 | 2019-09-20 | Note | False Fire 2019.261 VNP14IMG Occasional instances of false fire anomalies are observed in the NRT and OPS processing of 375m resolution Fire product (VNP14IMG). On September 18th, 2019 (2019.261) a fire anomaly was observed in granule 18:06 during a daytime orbit over South America. This spurious fire was caused by bad input L1B DATA (NPP_VIAES_L1) generated by the Land SIPS L1B SDR process and is commonly associated with rows of highly anomalous data values in the range of 57000's observed in the I4 band that are flagged as good quality in the band quality dataset. The example images below show the false fire in VNP14IMG fire product and the associated I4 L1B data for granule 18:06, 2019.261. Note that processing of the same product using the NASA L1B (VNP02IMG) is not expected to produce any such false fire because the same scan lines in the NASA L1B (in AS 5110 of LAADS) records a fill value of 65532 with a QA flag of 512 - both meaning missing earth view observation.<br><br> |
PM_NPP_L1B_19191 | 2019-07-23 | 2019-07-23 | Note | Missing data packets 2019.191 - 2019.198 due to contact error On 2019.191 (07.10.19) through 2019.198 (07.17.19) the SNPP VIIRS instrument experienced a series of missing data packets, which stemmed from a contact issue at the Svalbard ground station starting on 2019.191. This issue was resolved on 07.17.19 and the VIIRS instrument data has returned to nominal operations. However, during this time period a number of L1B granules were directly impacted and found to contain stripes of fill values. In some cases granules contained anomalous data values, which resulted in larger impacts to downstream products such as <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=346"> false fire</A>. The dates and times listed below document the L1B data, which were impacted. The example below show the impact to the L1B geolocation (only in some cases), L1B reflectance, and L1B thermal bands for dat 2019.191 granule 1824. <br><br>Impacted granules:<br>2019.191 (07.10.19) - 18:24 <br>2019.192 (07.11.19) - 01:24<br>2019.193 (07.12.19) - 17:30<br>2019.194 (07.13.19) - 09:12<br>2019.197 (07.16.19) - 03:00, 03:12<br>2019.198 (07.17.19) - 01:30, 01:36, 01:42, 01:48, 02:48, 09:12, 09:30<br><br> |
PM_NPP_VAFIP_19194 | 2019-07-17 | 2020-06-05 | Pending | False Fire 2019.192 through forward processing VNP14IMG / VNP14 Occasional instances of false fire anomalies are observed in the NRT and OPS processing of 375m resolution Fire product (VNP14IMG). Recently a series of fire anomalies were observed in the month of July 2019. These spurious fire were caused by the <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=456"> bad input L1B DATA (NPP_VIAES_L1)</A> generated by the Land SIPS L1B SDR process and are commonly associated with rows of highly anomalous data values in the range of 57000's observed in the I4 band that are flagged as good quality in the band quality dataset. The cause of this is currently under investigation, however the dates and granule impacted by this series of false fires in the VNP14IMG product are listed below. Additionally, the example images below show the false fire in VNP14IMG fire product and the associated I4 L1B data for granule 2019.194 09:12, where one such instance occurred. Note that processing of the same product using the NASA L1B (VNP02IMG) is not expected to produce any such false fire because the same scan lines in the NASA L1B (in AS 5110 of LAADS) records a fill value of 65532 with a QA flag of 512 - both meaning missing earth view observation.<br><br> |
PM_NPP_VAFIP_19032 | 2019-02-12 | 2019-02-12 | Note | False Fire 2019.032 (02.01.19) VNP14IMG A false fire anomaly was observed on February 1st, DOY 2019.032. The false fire occurred during a day time orbit over Greenland at the end of a data outage cause by <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=455"> a control processor (CP) reset</A>. Granule 15:00 was found to contain false fire in the VNP14IMG product and corrupt data in the associated upstream L1B. The first two images below show the false fire in VNP14IMG fire product and the associated I5 corrupted L1B data for granule 2019.032 15:00. The last image shows a spatial subset of the granule where the false fire is located. Users should be aware that this granule has been recommended to be removed from any future reprocessing. <br><br> |
PM_NPP_VAFIP_19037 | 2019-02-12 | 2019-02-12 | Note | False Fire 2019.037 (02.06.19) VNP14IMG A false fire anomaly was observed on February 6th, DOY 2019.037. The false fire occurred during a day time orbit over Newfoundland and is associated with corrupt input L1B data observed in the I5 band. The cause of this is currently under investigation, however granule 15:00 was found to contain false fire in the VNP14IMG product and corrupt data in the associated upstream L1B I5 band. The images below show the false fire in VNP14IMG fire product and the associated I5 corrupted L1B data for granule 2019.037 15:00.<br><br> |
PM_NPP_L1B_19032 | 2019-02-05 | 2019-02-05 | Note | Data loss on day 2019032 due to control processor reset On or February 01, 2019, there was a planned S-NPP Product Outage for the VIIRS instrument on S-NPP due to a control processor (CP) reset. Date/Time of Impact: February 1, 2019 1430Z through 1830Z. During this outage event no data was produced from period 14:36 through 14:48, inclusive. Additionally, granules 14:54 and 15:00 were found to contain corrupt geolocation and reflectance information. The first two images below show the L1B geolocation and reflectance layers from granule 15:00, which was found to be corrupt. The last image shows the global browse image where the data gap from this event is observed during a daytime orbit over a portion of Africa. <br><br><br> |
PM_NPP_L1B_19021 | 2019-01-21 | 2019-01-23 | Note | VIIRS SBC lock-up, 01.21.19 (2019.021) The VIIRS instrument experienced an anomaly on 01/21/2019 (2019.021) due to a VIIRS Single Board Computer (SBC) Lock-up. As a result, VIIRS science data output was impacted from 17:06z to 20:12z and no VIIRS data was collected for this period. This data loss is not recoverable. After this data loss occurred, the VIIRS instrument operated in Day mode from granule 20:24 through granule 23:30. During this period granules 20:24 through 21:00, granules 21:48 through 22:42, and granule 23:30 were all found to contain incorrect day night flag assignments. In all these cases the granules were collected in day mode during night time orbits. Finally, granules 20:18, 23:36 and 23:42 were found to be corrupt and contain artifacts in the geolocation information and associated thermal layers.<br><br>The data regions impacted by this event are daytime orbits over North and South America, where the data gap occurs from 16:54z to 20:24z. Additionally, Nighttime orbits over the Northern Pole, Asia, the Middle East and portions of Africa are impacted with incorrect flagged night granules. The first two images below show the impact of the event on the daytime surface reflectance and night time cloud mask data streams. The third and fourth images below show the artifacts found in the corrupt granule 23:36, observed in the latitude and the associated thermal band. |
TM_NPP_L1B_24208 | 2024-07-26 | 2024-07-31 | Note | S-NPP CDP Anomaly <h1>SNPP CDP Anomaly</h1>On July 24, 2024, 05:28:00Z, the SNPP satellite entered into a non-nominal state due to a Command Data Processor (CDP) reset anomaly. Loss of data began in revolution 66013. Attempts to recover data in the following revolutions were unsuccessful. SNPP returned to Mission Point mode as of July 24, 2024 18:22Z. VIIRS recovery efforts will continue next week. All SNPP data will be unavailable until further notice while recovery efforts and data quality evaluation is underway.<br><h2 style="text-align:center;">*** UPDATE 2 ***</h2><br>Geolocation team has evaluated the available data and reported nominal GCP residual values in the period from 07/24/2024 - 07/30/2024. The following figure demonstrates the nadir equivalent shift in meters of track vs scan data across the evaluated period. |
PM_NPP_VAFIP_18305 | 2018-11-08 | 2018-11-08 | Note | False Fire 2018.305 A false fire anomaly was observed on November 1st, DOY 2018.305. The False fire occurred during a day time orbit over Asia at the end of a data outage cause by <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=433"> the scan sync loss #97</A>. Granule 06:48 was found to contain false fire in the VNP14 product and corrupt data in the associated upstream L1B thermal band M13. The image below shows the false fire in VNP14 fire product and the associated M13 corrupted L1B data for granule 2018.305 06:48. While the M13 band and downstream VNP14 products are impacted in AS5000, this is corrected in the V2 L1B from reprocessing in AS 5110. AS5110 is not impacted during this period.<br><br> |
PM_NPP_L1B_18255 | 2018-09-13 | 2018-09-18 | Note | Data anomaly day 2018.255 On 2018.255 the S-NPP VIIRS instrument experienced a data anomaly, which was observed during multiple day and nighttime orbits over South America, Africa, Europe and Australia. The cause was due to quality issues associated with the spacecraft PDSs. Corrected PDS files for this data day were received and this day was reprocessed for AS5000 and AS5110 on 09.16.18 (2018.2579). Previously lost and degraded data for this DOY have been recovered in the L1B and downstream products. However, downstream degraded granules and <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=342">false fire</A> persisted during the nighttime orbits. Specifically, L1B granule 12:54 and 13:12 contained corrupt data and were removed from processing. Users should be aware that these two granules contain bad quality data and should not be used for analysis.<br><br>The images below show the corrupt L1B geolocation and brightness temperature band M13 for granule 13:12.<br><br> |
PM_NPP_VAFIP_18255 | 2018-09-13 | 2018-09-18 | Note | false fire 2018.255 (09.12.18) On 2018.255 the S-NPP VIIRS instrument experienced a data anomaly, which was observed during multiple day and nighttime orbits over South America, Africa, Europe and Australia. <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=453">The cause was due to quality issues associated with the spacecraft PDSs.</A> Corrected PDS files for this data day were received and this day was reprocessed for AS5000 and AS5110 on 09.16.18 (2018.2579). Previously lost and degraded data for this DOY have been recovered in the L1B and downstream products. However, downstream degraded granules and false fires persisted during the nighttime orbits. Specifically, L1B granules 12:54 and 13:12 contained corrupt data and were removed from processing. Users should be aware that these two granules contain bad quality data and should not be used for analysis. The first two images below show the global browse images of the daytime Active fire product for DOY 2018.255. The first image is the original global browse image generated using the corrupt PDS filles. The second image is the reprocessed global browse image generated using the most recent PDS files, where all the daytime fire anomalies and artifacts were resolved.<br><br><br> |
PM_NPP_VAFIP_18243 | 2018-09-11 | 2018-09-18 | Closed | false fire 2018.243 (08.31.18) On 2018.243 (August 31st, 2018) SNPP experienced degraded and non recoverable data from McMurdo, which impacted the VIIRS instrument data for the time period 12:57 to 13:06 GMT. This resulted in a <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=452">permanent data loss and a number of degraded granules.</A> Additionally, the degraded granule 12:54 produced a false fire downstream in the VNP14IMG product. This false fire occurred during a daytime orbit over Europe. The first image below shows the false fire in the NPP VIIRS active fire product for granule 12:54. The impacted granules have been flagged in the L1B and production is working to remove this granule from future processing. Until the granules are removed, users should be aware of the existing false fire due to this upstream data issue.<br><br>***NOTE***: Updated PDS files for this data day were received and this day was reprocessed for AS5000 and AS5110 on 09.14.18 (2018.257). All previously observed lost and degraded data for this DOY have been resolved in the L1B and downstream products (including false fire).The second image below shows the reprocessed granule 12:54, which resolved the previously observed false fire over Europe.<br><br> |
PM_NPP_L1B_18243 | 2018-09-06 | 2018-09-18 | Closed | Data Loss day 2018.243 (08.31.18) On 2018.243 (August 31st, 2018) SNPP experienced degraded and non recoverable data from McMurdo, which impacted the VIIRS instrument data for the time period 12:57 to 13:06 GMT. This resulted in a permanent data loss and a number of degraded granules. Granule 13:06 was unrecoverable and the surrounding granules were directly impacted. Granules 12:54 and 13:00 were found to contain corrupt geolocation and reflectance information. The data loss and impacted granules can be observed during a daytime orbit over Europe. Additionally, <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=341">false fire has been observed in the downstream production for granule 12:54.</A> Granule 13:06 was not produced, and granules 12:54 and 13:00 will be removed form the processing archive. The first two images below show an example of the impacted granule 13:00 geolocation and surface reflectance.<br><br>***NOTE***: Updated PDS files for this data day were received and this day was reprocessed for AS5000 and AS5110 on 09.14.18 (2018.257). All previously observed lost and degraded data for this DOY have been resolved in the L1B and downstream products. The third and fourth images below show the reprocessed granules, where the geolocation and reflectance artifacts have been resolved. <br><br> |
PM_NPP_VAFIP_18225 | 2018-08-14 | 2019-01-25 | Note | Lists of VNP14 and VNP14IMG corrupt and / or false fires L2 granules Some of the operational L2 fire product granules generated in AS 5000, from the V1 reprocessing, using the L1B data generated with IDPS Mx8 version of the Calibration code and NASA VCSTs Calibration LUT, are known to contain spurious fires from bad L1B data and other calibration related issues.<br><br>The first two examples below show the VNP14 and VNP14IMG L2 active fire product granules where false fires occur due to bad L1B data. A list of granules from each data product is provided, which identifies a number of granules that have been flagged with these related issues. Users are advised not to use these product granules. |
PM_NPP_VAFIP_18215 | 2018-08-03 | 2020-07-17 | Note | VNP14IMG fire pixels located outside wildfire perimeters False fire is observed outside wildfire perimeters in some cases when a super heated smoke plume can set off false fire during nighttime detection. This false fire artifact has been observed in the past, particularly at night in VNP14IMG. In these cases a hot plume is detected, which carries a signature that is easily confused with that of the "real" fire perimeter. The tall heat plume combined with the high view angle will be projected laterally on the surface, generating a false fire artifact. The artifacts are usually observed in the nighttime data as typically these super plumes tend to be flagged as clouds in the daytime scenes which prevents this detection. Users are advised to reference the VNP14 user guide in this <A href="https://viirsland.gsfc.nasa.gov/PDF/VIIRS_activefire_User_Guide.pdf">LINK</A> for more details. This issue has also been found to impact the fire product in the NOAA-20 (J1) VIIRS instrument.</A><br><br>The first image below is an example image from the FIRMS website, which shows the NPP VIIRS active fire product reporting a fire detected on July 26th, 2018 (2018.207) over Northern California's Whiskey Bottom lake. This is the projection of the false fire that is being detected by the active fire algorithm in the presence of a hot plume at high altitude over the true fire on the ground, which could be several kilometers away from the lake. The second image is section 5, the FREQUENTLY ASKED QUESTIONS of the VNP14 user guide, which explains this fire artifact in greater detail. |
PM_NPP_VAFIP_18212 | 2018-07-31 | 2019-01-10 | Note | High latitude data gaps during DNB calibration activity A series of high latitude data gaps have been observed in the Active Fire product during the monthly Day Night band calibration activity. This impacts both SNPP and <A href="https://landweb.modaps.eosdis.nasa.gov/displayissue?id=272">J1.</A> During the times of the DNB calibration some RSB M bands are substituted by DNB data for the calibration purpose, leading to the data loss in the fire product granules. The images below provide an example of this occurence during the July, 2018 DNB calibration event. <br><br>Similar impacts are observed for other DNB calibration activities. A complete list of the date and times for monthly SNPP DNB calibration events are regularly posted and updated <A href="https://landweb.modaps.eosdis.nasa.gov/dnbcali"> on this webpage.</A><br><br> |
PM_NPP_L1B_18186 | 2018-07-09 | 2018-07-09 | Note | Data Loss day 2018.186 On 2018.186 (July 5th, 2018) the VIIRS instrument on the SNPP Spacecraft experienced an anomaly, which resulted in a permanent data loss and a number of impacted granules. Some of the data will be unrecoverable and portions of the data were directly impacted. Granules 15:30, 19:24, 19:30, and 22:48 were found to contain corrupt geolocation and reflectance information. Additionally, granules 19:36 through 20:18 were found to be collecting in DAY MODE during a night time orbit. The data impact can be observed over Asia, where the instrument was collecting in day mode during a night time orbit. Additionally, off the West coast of South America the data impacted granule 15:30 is observed as a small gap. These granules will be removed form the processing archive as well as the global browse image. The images below show an example of the impacted granules and the global browse image. |
PM_NPP_L1B_18164 | 2018-06-13 | 2018-06-15 | Note | Change in radiometric calibration algorithms 2018.114 Land SIPS put in operation a change in calibration algorithm for the SNPP-VIIRS RSB. This change includes use of a new Delta-C LUT both in SDR (Mx8.11 based in AS 5000) and L1B (NASA VCST) calibration software as well as in the offline calibration processes that generates F-factor (a frequent update dynamic table). Use of this new delta LUT can result in a difference of 1% in the TOA reflectance for reflectance bands. Difference in TEBs could be much smaller. The change was put in operation in forward processing in AS 5000 on 5/19/2018 and in AS 5110 on 5/14/2018. No reprocessing of earlier mission period is planned at this time.<br><br><br> |
TM_NPP_L1B_24194 | 2024-07-12 | 2024-07-12 | Note | S-NPP GPS Anomaly 07/12/2024 <h1>SNPP GPS Anomaly</h1>On 07/09/2024 (2024/191), the S-NPP GPS receiver toggled to invalid at approximately 21:46:00z. The invalid GPS caused inaccurate geolocation of all observation data following the start of the anomaly. Engineering Team will perform a reset of the GPS unit no earlier than 07/12/2024. The NASA VIIRS/SNPP products for land and atmosphere have been suspended until further notice. Details of a previous SNPP GPS Anomaly can be found in this Known Issue : <a href = "https://landweb.modaps.eosdis.nasa.gov/displayissue?id=605"> SNPP GPS Anomaly May 5th, 2024 </a> Updates will be added to this rolling note documenting LDOPE and Geolocation Team evaluations, anomaly status updates, and product availability. |
PM_NPP_L1B_18044 | 2018-02-13 | 2018-02-14 | Note | NPP Product Outage/Anomaly, 02.13.18 (2018.044) The SNPP VIIRS Instrument entered SBC Lockup Mode at 1000Z (SLV 32632) on day 2018044 and returned back into science mode at ~12:48 GMT on the same day. Review of the data following the recovery of the instrument revealed granules 09:42 through 12:42 inclusive to be either missing from data loss, corrupt. These granules were removed from operational processing at Land SIPS and no downstream products were produced for these granules. The data granules impacted by this event are the day time orbits over Africa, the Middle East, Europe and a nighttime orbit over the Pacific ocean in the western hemisphere. The images below show the impacts of the event on the daytime global browse image L1B reflectance and nighttime active fire data streams. |
PM_NPP_L1B_18038 | 2018-02-07 | 2018-02-07 | Note | M11 missing data 01.29.18 through 01.30.18 On 2018.029 the VIIRS instrument experienced an anomaly due to an SBC Lockup/Petulant Mode. On the 29th through the 30th of January 2018 from the time 21:55z on the 29th until 18:05z on the 30th of January 2018, the Nighttime Products were impacted. The NOAA-IDPS engineers determined that M11 data was not being produced during this time period. At 1805z on 1.30.18 the spacecraft was commanded to provide M11 data in both day and night mode. Due to this anomaly, on 2018.029, the M11 radiance is missing from night time observations from 1/29/2018 21:55 through 1/30/2018 18:05.<br><br><br> |
PM_NPP_L1B_18029 | 2018-01-30 | 2018-01-30 | Note | Data Loss day 2018.029 On 2018.029 the VIIRS instrument on the SNPP Spacecraft experienced an anomaly, which resulted in a permanent data loss and a number of impacted granules. The data will be unrecoverable. Due to this anomaly granules 18:24 through 19:06, and 20:06 will be removed form processing. <br><br>Details:<br>16:18 is a partial graule, but good quality and will be processed<br>16:24 to 18:18 not produced, permanent data loss<br>18:24 bad data, not processed<br>18:30 to 19:06 night time orbit, but in day mode, not processed<br>19:12 to 20:00 day time orbit, day mode, all are good quality<br>20:06 is bad quality data, not processed.<br><br>The image below shows a global browse image of the NPP L1B reflectance data. The data outage can be observed over North and South America in the western hemisphere. Additionally, over Asia granules in a night time orbit are incorrectly collecting reflectance in day mode. These granules will be removed form the processing archive as well as the global browse image. |
PM_NPP_L1B_17272 | 2017-10-01 | 2017-10-01 | Note | no signal data during RFI period, 09.29.17 (2017.272) VIIRS went to 'Safe Mode' on 09/29/2017 (2017.272) at 13:01z. As a result, VIIRS science data output was impacted from 13:01z to 23:25z and no VIIRS data was collected for approximately ten (10) hours and twenty-four (24) minutes. The data regions impacted by this event are daytime orbits over the western hemisphere and nighttime orbits over the eastern hemisphere. The image below show the impacts of the event on the daytime surface reflectance and night time cloud mask data streams. All data missed during outage is nonrecoverable<br><br><br> |
PM_NPP_L1B_17239 | 2017-08-28 | 2017-08-30 | Note | VIIRS SBC lock-up, 08.27.17 (2017.239) VIIRS went into 'Petulant' Mode on 08/27/2017 (2017.239) due to a VIIRS Single Board Computer (SBC) Lock-up anomaly. As a result, VIIRS science data output was impacted and no VIIRS data was collected between 18:12 through 20:12 GMT. Granules 18:06 and 22:00 were found to be corrupt. Additionally, between 20:18 through 21:06, VIIRS was configured to operate in Day mode. Users should be aware that the data regions impacted by this event are daytime orbits over North America and Nighttime orbits over Asia, which correspond to the time periods above. Granules 21:42 and 21:54 contain geolocation artifacts, causing a small stripe of missing data over the West coast of North America and the North Pole. The images below show the impact of the event on the daytime surface reflectance and night time cloud mask data streams.<br><br> |
PM_NPP_L1B_17035 | 2017-02-22 | 2017-02-22 | Note | Data Loss day 2017.035 On 2017.035 a data loss was observed during a nighttime orbit over Southern Africa. The L1B thermal BT bands and geolocation layers were reviewed and granule 00:48 was found to contain a data loss in the BT M13 data bands, however the geolocation information was not impacted. The examples below show the L1 geolocation and BT data layers for this granule. The cause of this data loss is currently under investigation. |
PM_NPP_L1B_17034 | 2017-02-21 | 2017-02-21 | Note | Data Loss day 2017.034 On 2017.034 a data loss was observed during two nighttime orbits over Southern Africa and the Indian Ocean. The L1B thermal BT bands and geolocation layers were reviewed and granule 23:06 and 21:24 were found to contain a data loss in the BT M13 data bands, however the geolocation information was not impacted. The examples below show the L1 geolocation and reflectance data for these granules. The cause of this data loss is currently under investigation. |
PM_NPP_CM_17031 | 2017-02-01 | 2017-02-01 | Note | Fire Flag in Cloud Mask does not match Active Fire product The fire flag in the L2 Cloud Mask (VNP35_L2) does not match the detected fire flagged in the Active Fire product (VNP14) because of a coding error in cloud mask process. Impact of this in aerosol and surface reflectance is minimal. However, a fix has been implemented in forward processing as of 02.01.17. Below is an example of the Active Fire product and the associated Cloud Mask fire flag for the same region where few fires are observed. The third image shows the fixed cloud mask fire flag that has been implemented in forward processing as of 02.01.17 (2017.031).<br><br><br><br> |
PM_NPP_VAFIP_17029 | 2017-01-29 | 2017-01-29 | Note | False Fire 2017.029 A false fire anomaly was observed on January 29th, DOY 2017.029. The False fire occurred during a day time orbit off the coast of Northern Spain. Granule 13:54 was found to contain false fire and corrupt data in the associated upstream L1B thermal band I4. The image below shows the false fire in VNPIMG fire product and the associated I4 corrupted L1B data for granule 2017.029 13:54. |
PM_NPP_L1B_17024 | 2017-01-24 | 2024-06-14 | Note | Lunar Intrusion events data gap rolling record Lunar intrusion events routinely occur during the Lunar Roll Maneuvers and calibration activities. In some rare cases false fire is observed when L1B data reports poor M13 SDR quality in short segments of 4 adjacent orbits to a lunar roll maneuver. The cause is associated to an issue with the width of the exclusion / flagging zone for corrupted data, and results in spurious fire and striping artifacts. The poor M13 quality in short segments of adjacent orbits is observed in the global browse image during night time orbits of VNP35_L2(Cloud Mask) and both daytime and night time orbits VNP14C (Active Fire) products where the M13 band is referenced as input. The examples below shows one of these impacted days and also lists the occurrences of the known lunar intrusion events to date.<br><br><br> |
TM_NPP_L1B_24149 | 2024-05-28 | 2024-06-13 | Note | S-NPP GPS Anomaly <h1>SNPP GPS Anomaly</h1>On 5/25/2024, the S-NPP GPS started toggling from valid to invalid at approximately 22:23:14z before finally "latching" as invalid at 22:30:10z. As of the last pass, it has remained at invalid and mitigation steps are underway. Based on the geolocation teams investigation, the SNPP geolocation performance degradation is significant and exceeded 1km on 05/26/2024 (see below). The NASA VIIRS/SNPP/L2+ products for land/atmosphere/land has been suspended until further notice and only L1 product generation is underway for diagnosis purposes. |
PM_NPP_L1B_16355 | 2016-12-21 | 2016-12-21 | Note | VIIRS SBC lock-up, 12.20.16 (2016.355) VIIRS went to 'Petulant' Mode on 12/20/2016 (2016.355) at 18:30GMT due to a VIIRS Single Board Computer (SBC) Lock-up anomaly. As a result, VIIRS science data output was impacted from 18:30 GMT to 21:42 GMT and no VIIRS data was collected for approximately three (3) hours and twelve (12) minutes. Additionally, VIIRS was configured to operate in Day mode beginning at 21:47:29z. The data regions impacted by this event are daytime orbits over North America. Additionally, Nighttime orbits over Asia are impacted. The images below show the impact of the event on the daytime surface reflectance and night time cloud mask data streams.<br><br> |
PM_NPP_L1B_16315 | 2016-12-01 | 2016-12-01 | Note | Data loss on day 2016315 due to maneuver On November 15th, 2016.315 Suomi-NPP performed a VIIRS Lunar Roll Maneuver. For data day 2016.315, L1B SDR granule with start time 20:30, 20:36, and 20:42 were produced with fill values in the L1B data and geolocation layers. This resulted in a data gap in the L1B for this data day during a daytime orbit over portions of western North America. The images below show the L1B geolocation and reflectance layers from granule 20:30, where the data gap occurs. Additionally, the global browse image below shows the data gap in the reflectance product over North America during this maneuver period.<br> |
PM_NPP_L1B_12020 | 2016-11-17 | 2016-11-17 | Note | Data Gap 2012.020 (01/20/2012), VIIRS M-Band Reflectance On 2012.020, a data gaps were observed in the VIIRS Reflectance M-Bands. The gaps occurred in granules 04:06 and 12:36 during orbits passing over Eastern Asia and Europe. The first image of granule 12:36 below shows the data gap in the reflectance M5 band. The second image shows the corresponding latitude geolocation information. The geolocation information and thermal BT bands were reviewed and found to be nominal. |
PM_NPP_L1B_12019 | 2016-11-16 | 2016-11-16 | Note | Data Gap 2012.019 (01/19/2012), VIIRS M-Band Reflectance On 2012.019, a data gap was observed in the VIIRS Reflectance M-Bands. The gap occurred in granule 19:42 during an orbit passing over North America. The first image of the granule below shows the data gap in the reflectance M5 band. The second image shows the corresponding latitude geolocation information. No gap was observed in the geolocation information. |
PM_NPP_VAFIP_16292 | 2016-10-26 | 2016-10-26 | Note | False Fire 2016.292 A false fire anomaly was observed on October 18th, DOY 2016.292. The False fire occurred during a night time orbit off the coast of Brazil. Granule 03:18 was found to contain false fire and corrupt data in the associated upstream L1B thermal band I4. The image below shows the false fire in VNPIMG fire product and the associated I4 corrupted L1B data for granule 2016.292.03:18. |
PM_NPP_L1B_16226 | 2016-08-13 | 2016-08-13 | Note | VIIRS SBC lock-up, 08.13.16 (2016.226) VIIRS went to 'Petulant' Mode on 08/13/2016 (2016.226) at 18:06:34 GMT due to a VIIRS Single Board Computer (SBC) Lock-up anomaly. As a result, VIIRS science data output was impacted from 18:06:34 GMT to 20:23:00 GMT and no VIIRS data was collected for approximately two (2) hours and seventeen (17) minutes. Additionally, VIIRS was configured to operate in Day mode beginning at 20:23z, and continued in that mode until all necessary configuration files were uploaded over the next two orbits. <br><br>Therefore, Data collected between 20:23z and 23:50z was uncalibrated/degraded. The data regions impacted by this event are daytime orbits over North and South America. Additionally, Nighttime orbits over Asia are impacted. The images below show the impact of the event on the daytime surface reflectance and night time cloud mask data streams.<br><br><br><br> |
PM_NPP_VAFIP_16208 | 2016-07-28 | 2016-07-28 | Note | False Fire 2016.208 A false fire anomaly was observed on July 26th, DOY 2016.208. The False fire occurred during a daytime orbit over Russia. Granule 04:00 was found to contain false fire and corrupt data in the associated upstream L1B thermal band M14. The image below shows the false fire in VNPIMG fire product and the associated M14 corrupted L1B data for granule 2016.208.04:00. |
PM_NPP_CM_16152 | 2016-05-31 | 2016-05-31 | Note | Possible degradation of Cloud Mask, user discretion advised Cloud Mask product uses daily NISE (Near Real Time ice and snow extent) data as input seed for global ice concentration and snow extent. NISE data from day 096 of 2016 (4/5) may have been degraded as posted by the data center at this url (http://nsidc.org/data/search/#keywords=NISE/sortKeys=score,,desc/facetFilters=%257B%257D/pageNumber=1/itemsPerPage=25). Though visual inspection of the cloud product do not reveal any obvious quality issues in the cloud mask, users are advised to exercise caution while using the product in their application. All downstream land products may be affected by degradation in the Cloud Mask.<br><br><br><br> |
PM_NPP_L1B_16142 | 2016-05-24 | 2016-06-28 | Note | VMAE M4 band data gaps DOY 2016.141 and forward Multiple NPP_VMAE_L1 granules on May 20th(2016.141-146) were found to contain corrupt lines of data in the M4 or M5 reflectance band. The geolocation information was reviewed and no data corruption was observed. Additionally, all other bands were reviewed and were found to be nominal. However, the M4 or M5 Quality Flag reports a value of 1 for the corresponding lines where the issue occurs, which indicates poor quality data. The granules with the the corrupt M4 bands can be observed in the global browse images with a pink stripe. This is due to the M4 (green band) containing a value of zero. Below is an example showing a NPP_VMAE_L1 M4 band, where the corrupt lines of data are observed. This data issue is currently under investigation and is observed in the forward processing after DOY 2016.141. <br><br>Impacted L1 granules include:<br><br>2016.141<br>(M4) 14:50, (M4) 09:45, (M4) 08:15<br><br>2016.142<br>(M4) 18:00, (M4) 12:50, (M4)07:40<br><br>2016.143<br>(M4) 05:50<br><br>2016.144<br>(M4)05:15<br><br>2016.145<br>(M5) 20:20, (M4) 08:35, (M4) 11:45, (M4) 03:30<br><br>2016.146<br>(M5) 20:00, (M5) 10:05, (M4) 15:00<br><br><br><br>NOTE: A patch PGE500 was tested on nrt3 for day 2016141, and the stripes of fill were cleared from the granules that had contained them in the original run. The days where this issue is observed have been rerun for this period and this issue has been resolved. |
PM_NPP_L1B_16114 | 2016-04-26 | 2016-04-26 | Note | VIAE data corruption day 2016.114 The NPP_VIAE_L1 granule 18:05 on April 23, 2016.114 was found to contain a corrupt line of data in the I5 Imagery band. The geolocation information was reviewed and no data corruption was observed. The anomaly occurred during a daytime orbit off the coast of South America. Below is an example showing a spatial subset of the granule's I5 band, where the corrupt line of data is observed.<br><br><br> |
DF_NPP_L1B_231102 | 2023-11-02 | 2023-11-06 | Note | SNPP Outage JPSS NPP Stored Mission Data (SMD) is unavailable from 11/01/2023 - 16:30Z until further notice due to a spacecraft anomaly. SNPP experienced another CDP reset on 11/01/2023 and the Engineering team is trying to get the spacecraft into mission point and recover communications. So far, 3 out of 5 instruments are in safe mode. Efforts are underway to ascertain the telemetry from CrIS and VIIRS. The VIIRS science data is unavailable from ~14:50Z and the data production is on hold. Further updates will follow when more information is available.<br><br><font color='red'><b>Update 11/03/2023 (2023/307):</font></b> Engineering team placed the S-NPP satellite in mission-point mode and all instruments were confirmed to be in a safe state on Nov 1, 2023. Instrument activation activities commenced on Nov 2, 2023 and VIIRS was placed in operational mode at 16:09Z on Nov 2, 2023. S-NPP data is undergoing further evaluation by Cal/Val science teams and the VIIRS products may be reprocessed after the ongoing assessment of instrument performance by the NASA VCST. <br><br><font color='red'><b>Update 11/06/2023 (2023/310):</font></b>S-NPP instrument activation activities are on-going. All ATMS and VIIRS products are approved for operational use.<br><br> |
PM_NPP_L1B_16110 | 2016-04-20 | 2016-04-20 | Note | VIIRS Flight Software Update Data Corruption day 2016.110 On Tuesday April 19, 2016 the VIIRS instrument transitioned to a new flight software version (Ver. 0x4017). The flight software update caused periodic outages and degradation of the Day-Night Band.<br>VIIRS Data may be missing or corrupt during the following VIIRS flight software transition commanding windows:<br><br>SVL 23199: 13:01:39 - 13:15:51 UTC<br>SVL 23200: 14:43:40 - 14:57:15 UTC<br>SVL 23201: 16:27:01 - 16:39:07 UTC<br>SVL 23202: 18:10:31 - 18:21:10 UTC<br>SVL 23203: 19:53:18 - 20:04:19 UTC<br> SVL 23204: 21:35:19 - 21:48:14 UTC<br><br>Additionally, VIIRS operated in OP_Day mode for two orbits as a necessary step to minimize data impacts. Between 13:15 - 16:30 UTC, the VIIRS instrument went to OP_Day mode and did not executing day-to-night transitions. During that time, the visible bands produced daytime data during the nominal nighttime portion of the orbits. There will be no loss of data during this time period. In addition, the VIIRS Day-Night Band was degraded due to the flight software transition starting at approximately 14:45 UTC. The degradation ended at 18:20 UTC when all required DNB tables were loaded and activated. VIIRS returned to full nominal operations after 20:04 UTC.<br><br><br>Observed Data Impacts:<br><br>On 2016.110 two corrupt granules were observed over the Arctic. The L1B reflectance M bands, thermal BT bands and geolocation layers were reviewed and granules 21:35 and 21:40 were found to contain portions of corrupt data in the Reflectance, BT data bands, as well as the geolocation information. The examples below show the Reflectance M bands, the Brightness Temperature band 13, and the L1 geolocation information for granule 21:35.<br><br><br> NOTE: During processing for Land SIPS AS 5000, the 6 minute L1B granule 13:06 was found to be empty of scans and therefore it was not able to be processed. This 6-minute granule has been marked as Data Hidden From Production for future reprocessing efforts.<br><br><br> |
PM_NPP_L1B_16074 | 2016-03-17 | 2016-03-17 | Note | Data Loss day 2016.074 On 2016.074 a data loss was observed during a daytime orbit over the South Atlantic Ocean off the coast of South America. The L1B reflectance M bands, thermal BT bands and geolocation layers were reviewed and granule 15:35 was found to contain a data loss in the Reflectance and BT data bands, however the geolocation information was not impacted. The examples below show the L1 geolocation and reflectance data for this granule. The cause of this data loss is currently under investigation. |
PM_NPP_L1B_16063 | 2016-03-09 | 2016-03-09 | Note | Data Loss day 2016.063 On 2016.063 a data loss was observed during a daytime orbit over the Atlantic Ocean off the coast of Greenland. The L1B reflectance M bands, thermal BT bands and geolocation layers were reviewed and granule 16:05 was found to contain a data loss in the Reflectance and BT data bands, however the geolocation information was not impacted. The examples below show the L1 geolocation and reflectance data for this granule. The cause of this data loss is currently under investigation. |
PM_NPP_L1B_16062 | 2016-03-02 | 2024-02-16 | Note | VIIRS HAM Sync Data Loss Rolling Note The NPP VIIRS instrument experiences Half-Angle Mirror (HAM) sync errors, which result in data loss of the L1B and geolocation information. These are a self-recovering anomaly. The most probable root cause determined by Raytheon is the motor cable shielding on the RTA. About two inches of the RTA motor cable is not covered by the shielding and is exposed to the elements, which accounts for the long duration sync losses. The motor cable shielding on the HAM sees a small amount of exposure to the elements as well, which accounts for the short duration sync losses. These data losses can be observed as gaps in the L1B granules for the specified time periods reported. This rolling post will document the HAM sync errors.<br><br>History: The 67th and 68th were the 15th and 16th occurrences of this event in 2016. They have occurred on Day 35, 36, 37, 46, 52, 56(2), 70, 97, 114, 137, 155, 247, 257, and 293(2). All have been long or combination sync loss events. There were 11 events in 2015, 6 events in 2014, 11 events in 2013, 20 events in 2012, and 4 events in 2011. <br><br><br><br><br><br>#36. The 36th VIIRS scan sync loss occurred on 03/08/2014, data day 2014.067 from 16:29:26 to 16:31:06 UTC. This data loss occurred during the end of a daytime orbit over Northern Canada as the instrument was crossing the day/night line. The L1 data from the two granules 1625 and 1630 were reviewed. The data loss was only observed in granule 1625. Below, the first and second image show the latitude geolocation layer and the Brightness Temperature band M13 from the L1B NPP_VMAE for IDPS (AS3000). Both the data layers contain fill values for a portion of granule 1625. Additionally, the data loss was observed in both the IDPS and LPEATE data streams (3000 and 3001). The last two images show the latitude and Brightness Temperature band M13 for LPEATE (AS 3001). |
PM_NPP_L1B_16038 | 2016-02-10 | 2016-02-10 | Note | Data Loss day 2016.038 On 2016.038 a data loss was observed during a daytime orbit over the Atlantic Ocean off the coast of Africa. The L1B reflectance M bands, thermal BT bands and geolocation layers were reviewed and granule 15:20 was found to contain a data loss in the Reflectance and BT data bands, however the geolocation information was not impacted. The examples below show the L1 geolocation and reflectance data for this granule. The cause of this data loss is currently under investigation. |
PM_NPP_L1B_15357 | 2015-12-23 | 2015-12-23 | Note | Downstream artifacts from fill values during maneuver periods On Monday, December 21st, 2015.355 Suomi-NPP performed a VIIRS Lunar Roll Maneuver. For data day 2015.355, the L1B SDR granules 13:30, 13:35, and 13:40 were produced with fill values in the L1B data and geolocation layers. As expected, this resulted in a data gap in the L1B for this data day during a daytime orbit over Western Africa. However, downstream impacts were observed as stripe and artifacts in all of the gridded L2 and L3 data products for this region. The first image below shows the maneuver period where data loss is observed in the L1B reflectance product over Western Africa. The following images are examples of the impacts to the downstream gridded products. The cause of the downstream artifact is a mishandling of fill values during the generation of the L2G and L3 data products.<br><br><br> |
PM_NPP_L1B_15349 | 2015-12-16 | 2015-12-16 | Note | Corrupt L1B Reflectance, M6, M7 bands 2015.292-293 On October 19th, 2015 (2015.292) data corruption was observed in Land SIPS AS 3001 and AS 3110 (C11) L1B reflectance granules for bands M6 and M7. Granules from day of year 2015.292 21:30 through 2015.293 10:00 contain fill values in band M7 and corrupt data in bands M6. The first two images below are the global browse images for M7, which show the impacted regions. The 3rd image shows a L1B granule in AS3001 for bands M7, which reports fill values 65534 during a daytime orbit over the Pacific Ocean. The last image is the M6 band of the same granule, where corrupt values are observed as stripes throughout the granule. Only the M6 and M7 bands in the L1B data were observed to be impacted by this discrepancy. The cause of this data corruption is currently under investigation. |
PM_NPP_L1B_15336 | 2015-12-02 | 2016-01-06 | Note | New VIIRS-SDR-CAL-AUTOMATE-LUT 2015.334 IDPS promoted a new version of the VIIRS-SDR-CAL-AUTOMATE-LUT to their forward processing stream (AS3000) on 2015.334, data start date of 11/30/15 17:01. IDPS activated the VIIRS-SDR-CAL-AUTOMATE-LUT on 11/30 for calibration of the TOA reflectance and DNB SDRs. Due to some flaw in implementation of the same LUT at Land SIPS on 12.01.15 (2015.335), L1B generated at Land SIPS is out of sync with IDPS since 12/1/2015 with TOA reflectance being underestimated by as much as 10% compared to L1B generated by IDPS. This impacts all downstream products using the reflectance bands and the L1B DNB. Work is in progress to fix the issue in the Land SIPS L1B process or possibly adopt to use the predicted LUTs. The example below is the global difference image between IDPS and LPEATE L1B Reflectance band M1 for DOY 2015.339. <br><br><br> |
PM_NPP_L1B_15327 | 2015-11-23 | 2015-12-02 | Note | Data loss on day 2015326 due to maneuver On Sunday, November 22nd, 2015.326 Suomi-NPP performed a VIIRS Lunar Roll Maneuver. For data day 2015.326, L1B SDR granule with start time 04:15 could not be produced and granules 04:10, 04:20, and 04:25 were produced with fill values in the L1B data and geolocation layers. This resulted in a data gap in the L1B for this data day during a daytime orbit over portions of the Pacific Ocean and Eastern Asia. Additionally downstream impacts include stripes in the gridded surface reflectance for these regions. The image example below shows the period of data loss in the L1B reflectance product over the North Pacific Ocean.<br> |
PM_NPP_L1B_15275 | 2015-10-07 | 2015-10-07 | Note | High Latitude data loss DOY 2015275 On October 3rd, 2015 (DOY 2015275) there was a production Outage/Anomaly reported in the SNPP L1B IDPS product for times 0200 through 0220. The Land SIPS L1 NPP_VMAE_L1 product from day 2015275 was reviewed for this time period and includes granules at a high latitude polar region. The L1B for granules 02:10 and 02:15 were not produced, and granule 02:20 reported a data loss in the Thermal bands. The first image below shows the Land SIPS AS 3001, granule 02:20 NPP_VMAE Brightness Temperature band B13 with the data loss stipe. The second image shows the associated latitude geolocation, where no artifact or data loss was observed. |