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Full catalog/ASCATC-L2-Coastal
ASCATC-L2-Coastal·vOperational/Near-Real-Time·dataset

Ocean surface wind speed and direction near coasts (MetOp-C)

MetOp-C ASCAT Level 2 Ocean Surface Wind Vectors Optimized for Coastal Ocean
ocean NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. Gives ocean-surface wind speed and direction, tuned to provide reliable readings close to coastlines (as near as about 15 km from land), updated roughly every two hours.

How it's made. Derived from the ASCAT scatterometer on Europe's MetOp-C satellite, which measures microwave backscatter from the sea; a coastal-optimized averaging method converts it into winds.

How & where you'd use it. Useful for marine and coastal weather forecasting, navigation safety, and ocean-atmosphere research near shore.

What's measured

OCEANS › OCEAN WINDS › SURFACE WINDS › OCEAN SURFACE WIND VECTORS

Coverage & cadence

  • Time span2019-10-22 → ongoing
  • Measured byMETOP-C (ASCAT)
  • Processing levelLevel 2
  • Spatial extent-180, -89.6, 180, 89.6
  • 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

This dataset contains operational near-real-time Level 2 coastal ocean surface wind vector retrievals from the Advanced Scatterometer (ASCAT) on MetOp-C at 12.5 km sampling resolution (note: the effective resolution is 25 km). It is a product of the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) Ocean and Sea Ice Satellite Application Facility (OSI SAF) provided through the Royal Netherlands Meteorological Institute (KNMI). This coastal dataset differs from the standard 12.5 and 25 km datasets in that it utilizes a spatial box filter (rather than the Hamming filter) to generate a spatial average of the Sigma-0 retrievals from the Level 1B dataset; all full resolution Sigma-0 retrievals within a 15 km radius of the wind vector cell centroid are used in the averaging. Since the full resolution L1B Sigma-0 retrievals are used, all non-sea retrievals are discarded prior to the Sigma-0 averaging. Each box average Sigma-0 is then used to compute the wind vector cell using the same CMOD7.n geophysical model function as in the standard OSI SAF ASCAT wind vector datasets. With this enhanced coastal retrieval, winds can be computed as close to ~15 km from the coast. Each file is provided in netCDF version 3 format, and contains one full orbit derived from 3-minute orbit granules. Latency is approximately 2 hours from the latest measurement. The beginning of the orbit is defined by the first wind vector cell measurement within the first 3-minute orbit granule that starts north of the Equator in the ascending node. ASCAT is a C-band dual swath fan beam radar scatterometer providing two independent swaths of backscatter retrievals in sun-synchronous polar orbit aboard the MetOp-C platform. For more information on the MetOp-C mission, please visit: https://www.eumetsat.int/our-satellites/metop-series . For more timely announcements, users are encouraged to register with the KNMI scatterometer email list: scat@knmi.nl. Users are also highly advised to check the dataset user guide periodically for updates and new information on known problems and issues. All intellectual property rights of the OSI SAF products belong to EUMETSAT. The use of these products is granted to every interested user, free of charge. If you wish to use these products, EUMETSAT's copyright credit must be shown by displaying the words "copyright (year) EUMETSAT" on each of the products used.

Get the data

ascatc-l2-coastal_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ASCATC-L2-Coastal",
    version="Operational/Near-Real-Time",
    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.