Monday, May 20, 2019

DOI:  10.5067/GHV20-2PO61

The PO.DAAC is pleased to announce the public release of the NOAA GHRSST VIIRS L2P/L3U v2.61 Datasets onboard the Suomi National Polar-orbiting Partnership (SNPP) and the NOAA-20 (N20); designated pre-launch as “Joint Polar Satellite System-1”, or JPSS-1 (i.e., J1) satellites. The v2.61 is an updated version from the current v2.60 SNPP VIIRS L2P/L3U datasets (DOI: 10.5067/GHVRS-2PO26, 10.5067/GHVRS-3UO26, 10.5067/GHV20-2PO26 and 10.5067/GHV20-3UO26). These datasets are processed with the NOAA Advanced Clear Sky Processor for Ocean (ACSPO) Sea Surface Temperature (SST) system, and produced operationally by the Office of Satellite and Product Operations (OSPO). The datasets are formatted as netCDF, in compliance with the Group for High Resolution Sea Surface Temperature (GHRSST) Data Processing Specification version 2.0 (GDS2). Detailed information regarding the GHRSST Level 2P/3U products are available from the GHRSST website and also via PO.DAAC’s GHRSST mission webpage. Several enhancements and updates over v2.60 are implemented in v2.61, including:

  1. Fixing artificial positive bias in the high latitudes--An artefact of the Look-Up Tables (LUTs) used in v2.60.

  2. For the first time, a complete record of NPP (Feb 2012 – present) and N20 (Jan 2018 – present) is released with v2.61.

The L2P datasets are mapped on the instrument native swath grid with 0.75 km (nadir) to 1.5 km (swath edge) spatial resolution, and organized into 10min granules, 144 per day with a daily data volume of 25 GB/day. The L3U datasets represent a gridded (at 0.02deg equiangular projection) version of L2P, assimilating 144 10min granules per day, with a daily volume of 0.6 GB/day.

These four datasets provide daily SST with global coverage, currently from 24 April 2019 onward. NOAA has future plans to back-fill the NPP and N20 L2P and L3U records back to Feb 2012 and Jan 2018, respectively, expected to be completed by the end of 2019.

The datasets are described and discoverable via the PO.DAAC dataset information pages. The dataset information pages also provide access to the technical documentation and guidance on how to cite the data.

Citation: Petrenko, B., A. Ignatov, Y. Kihai, J. Stroup, and P. Dash, 2014, Evaluation and selection of SST regression algorithms for JPSS VIIRS, JGR, 119, doi: 10.1002/2013JD020637

Comments/Questions? Please contact or visit the PO.DAAC Forum.

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