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Full catalog/VIIRS_N20-STAR-L3U-v2.80
VIIRS_N20-STAR-L3U-v2.80·v2.80·dataset

How warm the sea surface is (VIIRS, NOAA-20)

GHRSST Level 3U NOAA STAR SST v2.80 from VIIRS on NOAA-20 Satellite
ocean NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. How warm the surface of the ocean is, mapped onto a grid, along with extras like wind speed and flags marking day, night, ice, and Sun glare.

How it's made. Calculated from the VIIRS instrument on the NOAA-20 satellite, then placed onto a regular grid in short 10-minute snapshots.

How & where you'd use it. Used for tracking ocean temperatures, supporting weather and climate studies, and feeding into marine and fisheries applications.

What's measured

OCEANS › OCEAN TEMPERATURE › SEA SURFACE TEMPERATURE › Skin Sea Surface Temperature

Coverage & cadence

  • Time span2018-01-05 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

NOAA-20 (N20/JPSS-1/J1) is the second satellite in the US NOAA latest generation Joint Polar Satellite System (JPSS), launched on November 18, 2017. The ACSPO N20/VIIRS L3U (Level 3 Uncollated) product is a gridded version of the ACSPO N20/VIIRS L2P product available here https://podaac.jpl.nasa.gov/dataset/VIIRS_N20-STAR-L2P-v2.80. The L3U output files are 10-minute granules in netCDF4 format, compliant with the Group for High Resolution Sea Surface Temperature (GHRSST) Data Specification version 2 (GDS2). There are 144 granules per 24hr interval, with a total data volume of 0.5GB/day. Fill values are reported at all invalid pixels, including pixels with >5 km inland. For each valid water pixel (defined as ocean, sea, lake or river, and up to 5 km inland), the following layers are reported: SSTs, a subset of l2p_flags (including day/night, land, ice, twilight, and glint flags), wind speed, and ACSPO SST minus reference (Canadian Met Centre 0.1deg L4 SST; available at https://www.doi.org/10.5067/GHCMC-4FM03). Only L2P SSTs with QL=5 were gridded, so all valid SSTs are recommended for the users. Per GDS2 specifications, two additional Sensor-Specific Error Statistics layers (SSES bias and standard deviation) are reported in each pixel with valid SST. The ACSPO VIIRS L3U product is monitored and validated against iQuam in situ data in SQUAM. The v2.80 is an updated version from the v2.61 with several L2P algorithm improvements including two added thermal front layers, mitigated warm biases in the high latitudes, and improved clear-sky mask.

Get the data

viirs_n20-star-l3u-v2.80_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VIIRS_N20-STAR-L3U-v2.80",
    version="2.80",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from POCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.