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data.MetOpAVHRR

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Import path: earth2studio.data.MetOpAVHRR

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Documentation

EUMETSAT MetOp AVHRR Level 1B radiance and brightness temperature observations.

The Advanced Very High Resolution Radiometer (AVHRR) is a 6-channel cross-track scanning radiometer aboard the MetOp series of polar-orbiting satellites. It measures calibrated radiances in visible (0.58-1.6 µm) and infrared (3.7-12.5 µm) bands at 1 km spatial resolution.

Channels 1-2 and 3A provide reflectances (visible/NIR), while channels 3B, 4, and 5 provide brightness temperatures (thermal IR). Channels 3A and 3B cannot operate simultaneously.

The returned DataFrame has one row per pixel per channel, following the same convention as [UFSObsSat][earth2studio.data.UFSObsSat]. The sensor_index column (1--6) identifies each channel. The class column differentiates observation types: "refl" for visible/NIR channels (1, 2, 3A) and "rad" for thermal IR channels (3B, 4, 5).

This data source downloads Level 1B products from the EUMETSAT Data Store and parses the EPS native binary format directly. Calibration coefficients are read from the GIADR-radiance record; visible channels are converted to reflectance (%), thermal channels to brightness temperature (K).

Geolocation uses the 103 EPS navigation tie points per scan line (~20 km spacing), avoiding expensive full-resolution interpolation.

Parameters:

  • satellite (str, default: None ) –

    Satellite platform filter. One of "metop-a", "metop-b", "metop-c", or None (all available). By default None.

  • subsample (int, default: 1 ) –

    Scan-line subsampling factor. AVHRR produces ~1000+ scan lines per orbit; subsampling reduces data volume. By default 1.

  • time_tolerance (TimeTolerance, default: timedelta64(1, 'h') ) –

    Time tolerance window for filtering observations. Accepts a single value (symmetric ± window) or a tuple (lower, upper) for asymmetric windows, by default np.timedelta64(1, 'h')

  • cache (bool, default: True ) –

    Cache data source on local memory, by default True

  • verbose (bool, default: True ) –

    Print download progress and info, by default True

  • async_timeout (int, default: 600 ) –

    Time in seconds after which download will be cancelled if not finished, by default 600

Warning

This is a remote data source and can potentially download a large amount of data to your local machine for large requests. Each AVHRR orbit file is approximately 1 GB.

Note

Requires EUMETSAT Data Store credentials. Set the following environment variables:

  • EUMETSAT_CONSUMER_KEY: Your EUMETSAT API consumer key
  • EUMETSAT_CONSUMER_SECRET: Your EUMETSAT API consumer secret

Register at eoportal.eumetsat.int/ to obtain credentials.

Note

Additional information on the data repository:

__call__ 

__call__(
    time: datetime | list[datetime] | TimeArray,
    variable: str | list[str] | VariableArray,
    fields: str | list[str] | Schema | None = None,
) -> DataFrame

Function to get AVHRR radiance/brightness temperature observations.

Parameters:

  • time (datetime | list[datetime] | TimeArray) –

    Timestamps to return data for (UTC).

  • variable (str | list[str] | VariableArray) –

    Variables to return. Must be in MetOpAVHRRLexicon (e.g. ["avhrr"]).

  • fields (str | list[str] | Schema | None, default: None ) –

    Fields to include in output, by default None (all fields).

Returns:

  • DataFrame –

    AVHRR observation data in long format with one row per pixel per channel.

fetch async 

fetch(
    time: datetime | list[datetime] | TimeArray,
    variable: str | list[str] | VariableArray,
    fields: str | list[str] | Schema | None = None,
) -> DataFrame

Async function to get AVHRR data.

Parameters:

  • time (datetime | list[datetime] | TimeArray) –

    Timestamps to return data for (UTC).

  • variable (str | list[str] | VariableArray) –

    Variables to return. Must be in MetOpAVHRRLexicon (e.g. ["avhrr"]).

  • fields (str | list[str] | Schema | None, default: None ) –

    Fields to include in output, by default None (all fields).

Returns:

  • DataFrame –

    AVHRR observation data in long format with one row per pixel per channel.