HimawariAHI

class earth2studio.data.HimawariAHI(

satellite='himawari9',

lat_lon_bbox=None,

cache=True,

verbose=True,

async_timeout=600,

async_workers=16,

retries=3,

)

ASAU

Himawari-8/9 AHI (Advanced Himawari Imager) data source.

This data source provides access to Himawari-8 and Himawari-9 satellite imagery from the NOAA ISatSS L2 Full Disk product on AWS S3. The data uses the same geostationary fixed grid projection as GOES, with the satellite positioned at 140.7°E.

Each AHI channel is stored as tiled NetCDF files (88 tiles per channel). Higher-resolution channels (C01/C02/C04 at 1 km, C03 at 0.5 km) are downsampled to the 2 km grid via block averaging, producing a uniform 5500×5500 pixel Full Disk output for all 16 channels.

Parameters:

• satellite (str, optional) – Which Himawari satellite to use (‘himawari8’ or ‘himawari9’), by default ‘himawari9’

• lat_lon_bbox (tuple[float, float, float, float] | None, optional) – Bounding box (lat_min, lon_min, lat_max, lon_max) in degrees to crop the full-disk image. Only tiles that overlap the requested region are downloaded. When None the full disk is returned, by default None

• cache (bool, optional) – Cache data source on local memory, by default True

• verbose (bool, optional) – Print download progress, by default True

• async_timeout (int, optional) – Total timeout in seconds for the entire fetch operation, by default 600

• async_workers (int, optional) – Maximum number of concurrent async fetch tasks, by default 16

• retries (int, optional) – Number of retry attempts per failed fetch task with exponential backoff, by default 3

Warning

This is a remote data source and can potentially download a large amount of data to your local machine for large requests. Each full disk image consists of 88 tile files per channel.

Note

Additional information on the data repository:

• https://www.data.jma.go.jp/mscweb/en/himawari89/space_segment/spsg_ahi.html

• https://aws.amazon.com/marketplace/pp/prodview-eu33kalocbhiw

• https://noaa-himawari9.s3.amazonaws.com/index.html

__call__(time, variable)

Function to get Himawari AHI data.

Parameters:

• time (datetime | list[datetime] | TimeArray) – Timestamps to return data for (UTC). Timezone-aware datetimes are converted to UTC automatically.

• variable (str | list[str] | VariableArray) – String, list of strings or array of strings that refer to variables to return. Must be in the Himawari lexicon (ahi01-ahi16).

Returns:

Data array with dimensions [time, variable, y, x]

Return type:

xr.DataArray

async fetch(time, variable)

Async function to get Himawari AHI data.

Parameters:

• time (datetime | list[datetime] | TimeArray) – Timestamps to return data for (UTC).

• variable (str | list[str] | VariableArray) – Variables to return using standardized names (ahi01-ahi16).

Returns:

Data array with dimensions [time, variable, y, x]

Return type:

xr.DataArray

classmethod available(time, satellite='himawari9')

Check if given date time is available in the Himawari object store.

Performs a lightweight S3 listing to verify that data files actually exist for the requested time, accounting for potential data gaps.

Parameters:

• time (datetime | np.datetime64) – Date time to check

• satellite (str, optional) – Which satellite to check, by default ‘himawari9’

Returns:

If date time is available

Return type:

bool