NASA Earth Science Data Records
The NASA ROSES call for the Suomi-NPP (SNPP) Science Team included both a Science Team component, that would produce NASA Earth Observing System (EOS) continuity data products, and also for the establishment of multiple Science Investigator-led Processing Systems (SIPS), that would produce the science data products developed by the science teams.
The science team focuses on producing refined and/or new data products in addition to the standard Earth System Data Records (ESDRs). In this way, NASA assures the continuity of high-quality EOS data products for Earth system science and applications available to all users.
In order to generate and distribute the NASA SNPP VIIRS Land science team products, the teams must first deliver Algorithm Theoretical Basis Documents (ATBDs) prior to operational processing at the NASA SIPS. Once this transition occurs, the data can be delivered for long-term archiving and distribution through one of the Distributed Active Archive Centers (DAACs). Most of the VIIRS Land products have their heritage in the MODIS Land product algorithms. The VIIRS Land Discipline Team, the Land SIPS, and the Validation leads have priorities and phased plans for producing Suomi NPP Land Science Products (see table below).
Note that the VIIRS Collection 2 (C2) reprocessing also includes the JPSS-1 (now NOAA-20) VIIRS, and the cross calibration of SNPP and NOAA-20 to provide continuity with MODIS, using Aqua MODIS as the reference sensor.
- Algorithms delivered and integrated to SIPS
- Products available to public from DAACs
- ATBDs and User Guides available
- Forward processing of C1 has been discontinued, except for the BRDF/Albedo and Black Marble products
- The forward processing of BRDF/Albedo and Black Marble will continue until C2 reprocessing has completed for the full mission period for SNPP
- These products were not part of Collection 1
- Reprocessing of mission period data complete for SNPP and NOAA-20 and forward processing in progress
- ATBDs and User Guides available
- Reprocessing of SNPP & NOAA-20 (2018 forward) began in Spring 2024
- Early mission period (2012-2017) reprocessing will follow
- Some ATBDs available
- Algorithms delivered to SIPS
- Product Integration and Testing continues
- Some ATBDs available
NASA's VIIRS Land SIPS generate science data products using algorithms and software developed by the SNPP science teams and delivers the products to NASA-designated DAACs for archive and distribution.
The latest version with the best and most current algorithms is the processing known as VIIRS Collection 2 or C2, except for two products, as described in the C1 table above.
VIIRS Processing by the Land SIPS
Land SIPS processing is separated into three separate modes, all operating simultaneously:
- Standard Processing Mode
- Near Real-Time (NRT) Processing Mode
- Experimental Reprocessing and Evaluation Mode
Creates the best possible science quality global VIIRS Level-1B and Land Level-2/Level-3 products that are processed and reprocessed. This uses the highest fidelity input data sources (requires 24-48 hour delay). Land L2/L3 products are delivered to LP and NSIDC DAACs.
Creates low latency (< 3 hours) global VIIRS products only in the forward stream within the Land, Atmosphere Near Real-Time Capability for EOS (LANCE) system.
Creatse global VIIRS L1B and Land L2/L3 test for review and evaluation by the SNPP Science Team.
