satpy.readers.ahi_l1b_gridded_bin module

Advanced Himawari Imager (AHI) gridded format data reader.

This data comes in a flat binary format on a fixed grid, and needs to have calibration coefficients applied to it in order to retrieve reflectance or BT. LUTs can be downloaded at: ftp://hmwr829gr.cr.chiba-u.ac.jp/gridded/FD/support/

This data is gridded from the original Himawari geometry. To our knowledge, only full disk grids are available, not for the Meso or Japan rapid scans.

References

class satpy.readers.ahi_l1b_gridded_bin.AHIGriddedFileHandler(filename, filename_info, filetype_info)[source]

Bases: BaseFileHandler

AHI gridded format reader.

This data is flat binary, big endian unsigned short. It covers the region 85E -> 205E, 60N -> 60S at variable resolution: - 0.005 degrees for Band 3 - 0.01 degrees for Bands 1, 2 and 4 - 0.02 degrees for all other bands. These are approximately equivalent to 0.5, 1 and 2km.

Files can either be zipped with bz2 compression (like the HSD format data), or can be uncompressed flat binary.

Initialize the reader.

_calibrate(data)[source]

Load calibration from LUT and apply.

static _download_luts(file_name)[source]

Download LUTs from remote server.

_get_luts()[source]

Download the LUTs needed for count->Refl/BT conversion.

_load_lut()[source]

Determine if LUT is available and, if not, download it.

_read_data(fp_)[source]

Read raw binary data from file.

static _untar_luts(tarred_file, outdir)[source]

Uncompress downloaded LUTs, which are a tarball.

calibrate(data, calib)[source]

Calibrate the data.

get_area_def(dsid)[source]

Get the area definition.

This is fixed, but not defined in the file. So we must generate it ourselves with some assumptions.

get_dataset(key, info)[source]

Get the dataset.

read_band(key, info)[source]

Read the data.