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Ocean color data from the VIIRS sensor aboard the S-NPP satellite are provided as a global life-of-mission science quality collection starting from November 2011.

Data are available through:

Datasets can be previewed and downloaded using the VIIRS Granule Selector.

Data are processed using NOAA MSL12 ocean color data processing system (SCI_OC03_V1.10). This science quality collection differs from the S-NPP-VIIRS near real time products in several ways:

Science QualityNear real-time
Latency Delayed 2 weeks ~12 hours (best effort)
Sensor Data Record(SDR) Ocean Color improved SDR IDPS Operational SDR
Ancillary Data Assimilated Predicted
Spatial Coverage Complete May have gaps

Standard S-NPP-VIIRS data products include:

  • Normalized water-leaving (nLw)radiance at five visible bands (nominal center wavelengths)
    • M1 (410nm)
    • M2 (443nm)
    • M3 (486nm)
    • M4 (551nm)
    • M5 (671nm)
  • Chlorophyll-a concentration
  • Diffuse attenuation coefficient at 490nm(Kd490), and
  • Diffuse attenuation coefficient of the photosynthetically available radiation (KdPAR)

Additional metadata can be obtained using THREDDS services such as ISO or OPeNDAP.

Level-2 products are organized by Year and Day-of-the-Year. Filenames will appear as follows: where:

  • V: Sensor VIIRS
  • 2011: Year of observation
  • 355: Day of year for the observation
  • 013534: Hour, minutes, and seconds of the start of observation (hhmmss) in UTC
  • NPP: Spacecraft S-NPP
  • SCINIR: Sensor data record source and environmental data record algorithm. SCI = ocean color SDR and NIR = near-infrared
  • L2: Processing level. L2 includes calibrated and geolocated geophysical products

Data files are in NetCDF4/CF but differ from past NOAA CoastWatch products in their use of hierarchical groups to store attributes, variables, and dimensions.

The CoastWatch Software has been updated to work with these files.