Add reader for EarthCARE MSI L1c data.

satpy/etc/composites/ec_msi.yaml

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+sensor_name: visir/ec_msi
+
+
+modifiers:
+  sunz_corrected:
+    modifier: !!python/name:satpy.modifiers.SunZenithCorrector
+
+  rayleigh_corrected:
+    modifier: !!python/name:satpy.modifiers.PSPRayleighReflectance
+    atmosphere: us-standard
+    aerosol_type: rayleigh_only
+    prerequisites:
+    - name: VIS
+      modifiers: [sunz_corrected]
+    optional_prerequisites:
+    - satellite_azimuth_angle
+    - satellite_zenith_angle
+    - solar_azimuth_angle
+    - solar_zenith_angle
+
+composites:
+  natural_color_nocorr:
+    compositor: !!python/name:satpy.composites.GenericCompositor
+    prerequisites:
+    - SWIR1
+    - NIR
+    - VIS
+    standard_name: natural_color
+
+  natural_color:
+    compositor: !!python/name:satpy.composites.GenericCompositor
+    prerequisites:
+    - name: SWIR1
+      modifiers: [sunz_corrected]
+    - name: NIR
+      modifiers: [sunz_corrected]
+    - name: VIS
+      modifiers: [sunz_corrected]
+    standard_name: natural_color

satpy/etc/readers/msi_l1c_earthcare.yaml

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+reader:
+  name: msi_l1c_earthcare
+  short_name: MSI EarthCARE
+  long_name: Multispectral Imager for EarthCARE
+  description: Multispectral Imager for EarthCARE Level 1C (regridded) Reader
+  status: Nominal
+  supports_fsspec: true
+  sensors: [ec_msi]
+  reader: !!python/name:satpy.readers.yaml_reader.FileYAMLReader
+
+
+file_types:
+  msi_l1c_earthcare_rgr:
+    file_reader: !!python/name:satpy.readers.msi_ec_l1c_h5.MSIECL1CFileHandler
+    file_patterns:
+      - '{mission_id:s}_{processing_institute:s}_{sensor_id:s}_{file_id:s}_{proc_level:s}_{start_time:%Y%m%dT%H%M%S}Z_{end_time:%Y%m%dT%H%M%S}Z_{orbit_number:s}{frame_id:s}.h5'
+
+
+datasets:
+# Science measurement datasets
+  VIS:
+    name: VIS
+    sensor: ec_msi
+    wavelength: [0.66, 0.67, 0.68]
+    resolution: 500
+    calibration:
+      reflectance:
+        standard_name: toa_bidirectional_reflectance
+        units: "%"
+      radiance:
+        standard_name: toa_outgoing_radiance
+        units: W m-2 sr-1
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 0
+    coordinates: [longitude, latitude]
+  NIR:
+    name: NIR
+    sensor: ec_msi
+    wavelength: [0.855, 0.865, 0.875]
+    resolution: 500
+    calibration:
+      reflectance:
+        standard_name: toa_bidirectional_reflectance
+        units: "%"
+      radiance:
+        standard_name: toa_outgoing_radiance
+        units: W m-2 sr-1
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 1
+    coordinates: [longitude, latitude]
+  SWIR1:
+    name: SWIR1
+    sensor: ec_msi
+    wavelength: [1.64, 1.67, 1.70]
+    resolution: 500
+    calibration:
+      reflectance:
+        standard_name: toa_bidirectional_reflectance
+        units: "%"
+      radiance:
+        standard_name: toa_outgoing_radiance
+        units: W m-2 sr-1
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 2
+    coordinates: [longitude, latitude]
+  SWIR2:
+    name: SWIR2
+    sensor: ec_msi
+    wavelength: [2.16, 2.21, 2.26]
+    resolution: 500
+    calibration:
+      reflectance:
+        standard_name: toa_bidirectional_reflectance
+        units: "%"
+      radiance:
+        standard_name: toa_outgoing_radiance
+        units: W m-2 sr-1
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 3
+    coordinates: [longitude, latitude]
+  TIR1:
+    name: TIR1
+    sensor: ec_msi
+    wavelength: [8.35, 8.80, 9.25]
+    resolution: 500
+    calibration:
+      brightness_temperature:
+        standard_name: toa_brightness_temperature
+        units: "K"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 4
+    coordinates: [longitude, latitude]
+  TIR2:
+    name: TIR2
+    sensor: ec_msi
+    wavelength: [10.35, 10.80, 11.25]
+    resolution: 500
+    calibration:
+      brightness_temperature:
+        standard_name: toa_brightness_temperature
+        units: "K"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 5
+    coordinates: [longitude, latitude]
+  TIR3:
+    name: TIR3
+    sensor: ec_msi
+    wavelength: [11.55,12.00,12.45]
+    resolution: 500
+    calibration:
+      brightness_temperature:
+        standard_name: toa_brightness_temperature
+        units: "K"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values
+    band_index: 6
+    coordinates: [longitude, latitude]
+
+  # Relative error datasets
+  VIS_rel_error:
+    name: VIS_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_radiance
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 0
+  NIR_rel_error:
+    name: NIR_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_radiance
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 1
+  SWIR1_rel_error:
+    name: SWIR1_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_radiance
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 2
+  SWIR2_rel_error:
+    name: SWIR2_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_radiance
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 3
+  TIR1_rel_error:
+    name: TIR1_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_brightness_temperature
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 4
+  TIR2_rel_error:
+    name: TIR2_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_brightness_temperature
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 5
+  TIR3_rel_error:
+    name: TIR3_rel_error
+    sensor: ec_msi
+    resolution: 500
+    standard_name: relative_error_in_toa_brightness_temperature
+    units: "%"
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/pixel_values_relative_error
+    band_index: 6
+
+# Geolocation data
+  longitude:
+    name: longitude
+    units: degrees_east
+    standard_name: longitude
+    resolution: 500
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/longitude
+  latitude:
+    name: latitude
+    units: degrees_north
+    standard_name: latitude
+    resolution: 500
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/latitude
+  solar_azimuth_angle:
+    name: solar_azimuth_angle
+    units: degree
+    standard_name: solar_azimuth_angle
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/solar_azimuth_angle
+  sensor_azimuth_angle:
+    name: sensor_azimuth_angle
+    units: degree
+    standard_name: sensor_azimuth_angle
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/sensor_azimuth_angle
+  sensor_view_angle:
+    name: sensor_zenith_angle
+    units: degree
+    standard_name: sensor_zenith_angle
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: NonStandard/sensor_view_angle
+  solar_zenith_angle:
+    name: solar_zenith_angle
+    units: degree
+    standard_name: solar_zenith_angle
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: NonStandard/solar_zenith_angle
+
+# Ancillary data
+  land_flag:
+    name: land_water_mask
+    units: 1
+    standard_name: land_water_mask
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/land_flag
+  surface_elevation:
+    name: surface_elevation
+    units: m
+    standard_name: surface_elevation
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: ScienceData/surface_elevation
+  surface_index:
+    name: surface_index
+    units: 1
+    standard_name: surface_index
+    resolution: 500
+    coordinates: [longitude, latitude]
+    file_type: msi_l1c_earthcare_rgr
+    file_key: NonStandard/surface_index

satpy/readers/msi_ec_l1c_h5.py

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+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# Copyright (c) 2024.
+#
+# This file is part of satpy.
+#
+# satpy is free software: you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the Free Software
+# Foundation, either version 3 of the License, or (at your option) any later
+# version.
+#
+# satpy is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# satpy.  If not, see <http://www.gnu.org/licenses/>.
+"""A reader for Level 1C data produced by the MSI instrument aboard EarthCARE."""
+import logging
+
+from satpy.readers.hdf5_utils import HDF5FileHandler
+from satpy.utils import get_legacy_chunk_size
+
+LOG = logging.getLogger(__name__)
+CHUNK_SIZE = get_legacy_chunk_size()
+
+
+class MSIECL1CFileHandler(HDF5FileHandler):
+    """File handler for MSI L1c H5 files."""
+
+    def __init__(self, filename, filename_info, filetype_info):
+        """Init the file handler."""
+        super(MSIECL1CFileHandler, self).__init__(filename,
+                                                  filename_info,
+                                                  filetype_info)
+
+    @property
+    def end_time(self):
+        """Get end time."""
+        return self.filename_info["end_time"]
+
+    @property
+    def start_time(self):
+        """Get start time."""
+        return self.filename_info["start_time"]
+
+    def get_dataset(self, dataset_id, ds_info):
+        """Load data variable and metadata and calibrate if needed."""
+        file_key = ds_info.get("file_key", dataset_id["name"])
+        data = self[file_key]
+
+        # Band data is stored in a 3d array (Band x Along_Track x Across_Track).
+        # This means we have to select a single 2d array for a given band,
+        # and the correct index is given in the reader YAML.
+        band_index = ds_info.get("band_index")
+        if band_index is not None:
+            data = data[band_index]
+
+        # The dataset has incorrect units attribute (due to storing multiple types). Fix it here.
+        data.attrs.update(ds_info)
+        data.attrs.update({"units": ds_info.get("units")})
+
+        # VIS/SWIR data can have radiance or reflectance calibration.
+        if "calibration" in ds_info:
+            if ds_info["calibration"].name == "reflectance":
+                data = self._calibrate(data, band_index)
+            elif ds_info["calibration"].name not in ["radiance", "brightness_temperature"]:
+                raise ValueError(f"Unknown calibration type:{ds_info['calibration'].name}")
+
+        # Rename dimensions, as some have incorrect names (notably the pixel value data).
+        if "dim_1" in data.dims:
+            data = data.rename({"dim_1": "y", "dim_2": "x"})
+
+        # The dimension list is usually a reference to an H5 variable, which is problematic
+        # when making a copy of the data. This sorts out the dimensions and sets them correctly
+        # following the process done in the OMPS reader.
+        if "DIMENSION_LIST" in data.attrs:
+            data.attrs.pop("DIMENSION_LIST")
+            dimensions = self.get_reference(file_key, "DIMENSION_LIST")
+            dim_dict = {}
+            # We have to loop over dimensions to match dim sizes as the pixel data is 3d rather than 2d.
+            for i in range(0, len(data.dims)):
+                c_dim = data.dims[i]
+                for r_dim in dimensions:
+                    if data.shape[i] == r_dim[0].shape[0]:
+                        dim_dict[c_dim] = r_dim[0]
+            data.assign_coords(dim_dict)
+        return data
+
+    def _calibrate(self, data, band_index):
+        """Calibrate the data."""
+        sol_irrad = self["NonStandard/solar_irradiance"]
+
+        return 100 * data / sol_irrad[band_index]