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Full catalog/N21-VIIRS-L3U-ACSPO-v2.80
N21-VIIRS-L3U-ACSPO-v2.80·v2.80·dataset

How warm the sea surface is (VIIRS NOAA-21)

GHRSST Level 3U NOAA ACSPO SST v2.80 from VIIRS on NOAA-21 Satellite
ocean NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. How warm the sea surface is just below the skin, mapped globally, along with quality flags, nearby wind speed, and the difference from a reference temperature.

How it's made. Derived by NOAA's ACSPO system from the VIIRS instrument aboard the NOAA-21 satellite, gridded into 10-minute granules from higher-detail input data.

How & where you'd use it. Supports weather forecasting, ocean monitoring, and climate research that rely on sea surface temperature.

What's measured

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

Coverage & cadence

  • Time span2023-03-19 → ongoing
  • Measured byNOAA-21 (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

The N21-VIIRS-L3U-ACSPO-v2.80 dataset produced by the NOAA ACSPO system derives the Subskin Sea Surface Temperature (SST) from the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Joint Polar Satellite System (JPSS)-2 satellite, renamed as NOAA-21 (N21). N21 was launched on Nov. 10, 2022, the 3rd satellite in the US NOAA latest JPSS series. The ACSPO N21 VIIRS L3U (Level 3 Uncollated) product is a gridded version of the ACSPO N21 VIIRS L2P product, also available at PO.DAAC (10.5067/GHV21-2P280). 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). The ACSPO N21 VIIRS SST record is available back to 19 Mar 2023. There are 144 granules per 24 hour interval, with a total data volume of 0.6GB/day. Fill values are reported at all invalid pixels, including pixels >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: SST, a subset of variable l2p_flags (including day/night, land, ice, twilight, and glint flags), wind speed, and the SST minus reference CMC SST (Canadian Met Centre 0.1deg L4 SST, 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 quality controlled in situ data provided by NOAA in situ SST Quality Monitor system (iQuam) using another NOAA system, SST Quality Monitor (SQUAM).

Get the data

n21-viirs-l3u-acspo-v2.80_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="N21-VIIRS-L3U-ACSPO-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.