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Full catalog/L3S_LEO_PM-STAR-v2.81
L3S_LEO_PM-STAR-v2.81·v2.81·dataset

How warm the sea surface is (afternoon satellites, 0.02 deg)

GHRSST NOAA/STAR ACSPO v2.81 0.02 degree L3S Dataset from Afternoon LEO Satellites
ocean NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. How warm the sea surface is (sea surface temperature, just below the skin layer), mapped on a fine global grid at about 0.02 degrees.

How it's made. Blends temperature readings from VIIRS sensors on the Suomi-NPP, NOAA-20, and NOAA-21 satellites plus MODIS on Aqua, all flown on afternoon-passing orbits, into one combined gridded product.

How & where you'd use it. Supports weather and ocean forecasting, climate monitoring, and studies of marine heatwaves and currents, with separate day and night versions.

What's measured

OCEANS › OCEAN TEMPERATURE › SEA SURFACE TEMPERATURE › SEA SURFACE SUBSKIN TEMPERATURE

Coverage & cadence

  • Time span2002-07-04 → ongoing
  • Measured bySuomi-NPP (VIIRS) · NOAA-20 (VIIRS) · NOAA-21 (VIIRS) · Aqua (MODIS)
  • 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 L3S_LEO_PM-STAR-v2.81 dataset produced by the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) system derives the Subskin Sea Surface Temperature (SST) from the VIIRSs (Visible Infrared Imaging Radiometer Suite) onboard the Suomi-NPP, NOAA-20 and NOAA-21 satellites and MODIS (Moderate Resolution Imaging Spectroradiometer) onboard the Aqua satellite. The L3S-LEO is a family of multi-sensor super-collated (L3S) gridded 0.02º resolution SST products from low earth orbit (LEO) satellites. The L3S-LEO-PM ( https://doi.org/10.5067/GHLPM-3S281 ) and AM ( https://doi.org/10.5067/GHLAM-3SS28 ) data include SSTs from afternoon (~1:30 am/pm) and mid-morning (~9:30 am/pm) satellites, respectively. The PM and AM SSTs, for both day (D) and night (N), and Terra MODIS SSTs, are further aggregated into a daily L3S-LEO-DY SST product ( https://doi.org/10.5067/GHLDY-3S281 ). This PM SST product is derived by collating individual satellite ACSPO L3U data ( https://doi.org/10.5067/GHVRS-3UO61, https://doi.org/10.5067/GHV20-3UO61 and https://doi.org/10.5067/GHN21-3U280 ). It covers from 2002-07-04 to present and is reported in 2 files daily, day and night, at 1:30am/pm local time. The SST is in NetCDF4 format, compliant with the GHRSST Data Specification version 2 (GDS2). The v2.81 is updated from the previous v2.80 ( https://doi.org/10.5067/GHLPM-3SS28 ): (1) v2.81 includes 3 VIIRSs (NPP, N20, and N21 from 2023-03-19 - on); (2) Aqua MODIS SST included from 2002-07-04 to 2022-12-31; (3) Time series in v2.81 extended back to 2002-07-04 (from 2012-02-01 in v2.80); (4) recently uncovered VIIRS daytime SST drifts in NPP and N20 SSTs of approximately -0.1 K/decade mitigated. The Near Real Time (NRT) data are available with 6h latency, and replaced by the Re-ANalysis (RAN) files in 2 months, with identical file names. They can be differentiated by the file creation time and ancillary inputs. The data are validated against quality controlled in situ data from the NOAA in situ SST Quality Monitor (iQuam; https://www.star.nesdis.noaa.gov/socd/sst/iquam), and monitored in another NOAA system, SST Quality Monitor (SQUAM; https://www.star.nesdis.noaa.gov/socd/sst/squam)

Get the data

l3s_leo_pm-star-v2.81_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="L3S_LEO_PM-STAR-v2.81",
    version="2.81",
    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.