satpy.readers.seviri_l1b_nc module
SEVIRI netcdf format reader.
- class satpy.readers.seviri_l1b_nc.NCSEVIRIFileHandler(filename, filename_info, filetype_info, ext_calib_coefs=None, mask_bad_quality_scan_lines=True)[source]
Bases:
BaseFileHandler
File handler for NC seviri files.
Calibration
See
satpy.readers.seviri_base
. Note that there is only one set of calibration coefficients available in the netCDF files and therefore there is no calib_mode argument.Metadata
See
satpy.readers.seviri_base
.Init the file handler.
- _get_calib_coefs(dataset, channel)[source]
Get coefficients for calibration from counts to radiance.
Only nominal calibration coefficients are available in netCDF files.
- property _repeat_cycle_duration
Get repeat cycle duration from the metadata.
- property end_time
Get the general end time for this file.
- get_area_def(dataset_id)[source]
Get the area def.
Note that the AreaDefinition area extents returned by this function for NetCDF data will be slightly different compared to the area extents returned by the SEVIRI HRIT reader. This is due to slightly different pixel size values when calculated using the data available in the files. E.g. for the 3 km grid:
NetCDF: self.nc.attrs['vis_ir_column_dir_grid_step'] == 3000.4031658172607
HRIT: np.deg2rad(2.**16 / pdict['lfac']) * pdict['h'] == 3000.4032785810186
This results in the Native 3 km full-disk area extents being approx. 20 cm shorter in each direction.
The method for calculating the area extents used by the HRIT reader (CFAC/LFAC mechanism) keeps the highest level of numeric precision and is used as reference by EUM. For this reason, the standard area definitions defined in the areas.yaml file correspond to the HRIT ones.
- property nc
Read the file.
- property nominal_end_time
Read the repeat cycle nominal end time from metadata and round it to expected nominal time slot.
- property nominal_start_time
Read the repeat cycle nominal start time from metadata and round it to expected nominal time slot.
- property observation_end_time
Get the repeat cycle observation end time from metadata.
- property observation_start_time
Get the repeat cycle observation start time from metadata.
- property satpos
Get actual satellite position in geodetic coordinates (WGS-84).
Evaluate orbit polynomials at the start time of the scan.
Returns: Longitude [deg east], Latitude [deg north] and Altitude [m]
- property start_time
Get general start time for this file.
- class satpy.readers.seviri_l1b_nc.NCSEVIRIHRVFileHandler(filename, filename_info, filetype_info, ext_calib_coefs=None, mask_bad_quality_scan_lines=True)[source]
Bases:
NCSEVIRIFileHandler
,SEVIRICalibrationHandler
HRV filehandler.
Init the file handler.