In the processing of Ocean Color (OC) data from sensor data recorded by Visible Infrared Imaging Radiometer Suite
(VIIRS) aboard JPSS-Suomi satellite, NASA Ocean Biology Processing Group (OBPG) is deriving a continuous
temporal calibration based on the on-board calibration measurements for the visible bands, and then reprocessing the full
mission to produce a continuously calibrated sensor data record (SDR) product. In addition, a vicarious calibration
during SDR to OC Level-2 processing is applied. In the latest processing the vicarious calibration is derived from the
Marine Optical Buoy (MOBY) data, whereas in the initial processing it was derived from a sea surface reflectance model
and a climatology of chlorophyll-a concentration. Furthermore, NASA has recently reprocessed the OC data for the
entire VIIRS mission with lunar-based temporal calibration and updated vicarious gains. On the other hand, in fulfilling
the mission of the U.S. National Oceanic and Atmospheric Administration (NOAA), the Interface Data Processing
Segment (IDPS) developed by Raytheon Intelligence and Information Systems, for the processing of the environmental
data products from sensor data records, has gained beta status for evaluation. As these processing schemes continue to
evolve, monitoring the validity and assessments of the related VIIRS ocean color products are necessary, especially for
coastal waters, to evaluate the consistency of these processing and calibration schemes. The ocean color component of
the Aerosol Robotic Network (AERONET-OC) has been designed to support long-term satellite ocean color
investigations through cross-site measurements collected by autonomous multispectral radiometer systems deployed
above water. As part of this network, the Long Island Sound Coastal Observatory (LISCO) near New York City and
WaveCIS in the Gulf of Mexico expand those observational capabilities with continuous monitoring as well as (for the
LISCO site) additional assessment of the hyper-spectral properties of coastal waters. In the investigations carried out
over a one and half year period dataset of VIIRS, based on the data from two coastal AERONET-OC sites, it has been
observed that the VIIRS sensor captures well the seasonal and temporal variations in the nLw data, exhibiting significant
correlation with in-situ data (R = 0.929 and 0.985 for LISCO and WaveCIS respectively). For the WaveCIS site, VIIRS
nLw data retrievals are seen to be enhanced with each incremental adjustments of vicarious and calibration procedures.
However, that is not the case for the LISCO site which exhibits more frequent occurrences of negative water-leaving
radiances, while underestimation in VIIRS nLw data is further exacerbated. Strong consistency between the time-series
nLw data retrieved from the VIIRS and MODIS sensors was also observed.
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