Release of NRT VIIRS Collection 2 (C2) Land products and decommissioning of C1 products

Updated 2023-11-03T13:30:00Z -- Please take note that MODAPS LANCE has disabled the distribution of most SNPP Collection 1 (C1) near real-time (NRT) land products, starting this week, from both nrt3 and nrt4, with the only exception of SNPP C1 BRDF/Albedo (VNP43) products. All SNPP land products, barring VNP43 suite, and all associated links from LANCE are switched to the Collection 2 (C2) variants, which are being generated since October 9, 2023. The C1 VNP43* will continue to be produced and distributed, till it is fully replaced with a C2 variant.

In addition, users can now access the full suite of NOAA-20 (J1) land products for the first time in LANCE, as part of C2. The full C2 BRDF/Albedo suite of products for both SNPP and J1 are currently under testing and science review and is expected to go into operation within the next couple of weeks. A further update will be sent out when these become available from LANCE.

All C2 land products for SNPP and J1 VIIRS have been generated using Level 1Bs that have been cross-calibrated for selected RSB VIS/NIR and SWIR bands to mitigate the bias in observed top of atmosphere (TOA) reflectance values, and to constrain them within 1%, using MODIS Aqua as the reference. For further details on C2 specific changes, users are requested to refer to this whitepaper on VIIRS C2 Land changes.

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Please note that all NRT VIIRS Collection 1 (C1) Land products will be switched to Collection 2 (C2) on or during the week of October 9, 2023. The C2 land products will be available from the folder 5200 on nrt3/nrt4. This will include the JPSS NOAA-20 (J1) near real-time (NRT) land products for the first time in LANCE. The C2 land products for SNPP and J1 VIIRS have been generated using Level 1Bs that have been cross-calibrated for selected RSB VIS/NIR and SWIR bands to mitigate the bias in observed top of atmosphere (TOA) reflectance values, and to constrain them within 1%, using MODIS Aqua as the reference. For further details on C2 specific changes, users are requested to refer to this whitepaper on VIIRS C2 Land changes. A further update will be sent out after the switch, and all C1 land products will eventually be decommissioned from nrt3/4 by the week of October 23.