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Full catalog/H09-AHI-L3C-ACSPO-v2.90
H09-AHI-L3C-ACSPO-v2.90·v2.90·dataset

How warm the Pacific sea surface is (Himawari-9)

GHRSST L3C NOAA/ACSPO Himawari-09 AHI Pacific Ocean Region Sea Surface Temperature v2.90 dataset
ocean NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. How warm the surface of the Pacific Ocean is, reported as sea surface temperature for each point on a fine map, with extra layers describing the expected error in each reading.

How it's made. Calculated by NOAA's ACSPO system from the Advanced Himawari Imager on the Himawari-9 satellite, then gridded onto a 0.02-degree map with 24 hourly snapshots per day.

How & where you'd use it. Supports weather forecasting, ocean and climate monitoring, and studies of how the Pacific's surface heat changes through the day.

What's measured

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

Coverage & cadence

  • Time span2022-10-22 → ongoing
  • Measured byHimawari-9 (AHI)
  • Processing levelLevel 3
  • Spatial extent80, -60, -160, 60
  • 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 H09-AHI-L3C-ACSPO-v2.90 dataset contains the Subskin Sea Surface Temperature (SST) produced by the NOAA ACSPO system from the Advanced Himawari Imager (AHI; largely identical to GOES-R/ABI) onboard the Himawari-9 (H09) satellite. The H09 is a Japanese weather satellite, the 9th of the Himawari geostationary weather satellite operated by the Japan Meteorological Agency. It was launched on November 2, 2016 into its nominal position at 140.7-deg E, and declared operational on December 13, 2022, replacing the Himawari-8. The AHI is the primary instrument on the Himawari Series for imaging Earth’s weather, oceans, and environment with high temporal and spatial resolutions. The H09-AHI-L3C-ACSPO-v2.90 dataset is a gridded version of the ACSPO H09-AHI-L2P-ACSPO-v2.90 dataset (https://podaac.jpl.nasa.gov/dataset/AHI_H09-STAR-L2P-v2.90). The L3C (Level 3 Collated) data is mapped on 0.02-deg lat-lon grid and outputs 24 hourly granules per day, with a daily volume of 0.7 GB/day. Valid SSTs are found over oceans, sea, lakes or rivers, with fill values reported elsewhere. All valid SSTs in L3C are recommended for users, although data over internal waters may not have enough in situ data to be adequately validated. Per GDS2 specifications, two additional Sensor-Specific Error Statistics layers (bias and standard deviation) are reported in each pixel with valid SST. The ACSPO H09/AHI L3C product is validated against iQuam in situ data (Xu and Ignatov, 2014) and continuously monitored in the NOAA SQUAM system (Dash et al, 2010). The NRT files are replaced with Delayed Mode (DM) files, with a latency of approximately 2-months. File names remain unchanged, and DM vs NRT can be identified by different time stamps and global attributes inside the files (MERRA for DM instead of GFS for atmospheric profiles, and same day CMC L4 analyses in DM instead of one-day delayed in NRT processing).

Get the data

h09-ahi-l3c-acspo-v2.90_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="H09-AHI-L3C-ACSPO-v2.90",
    version="2.90",
    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.