Dataset Description

The FAAM provided weather radar data are provided in a netCDF file. The file is essentially a low-level represention of the raw ARINC708 data, with the exception of the following:

• Range (nm)

• Tilt (deg)

• Gain (dB)

• Scan angle (deg)

which are all converted from their packed binary representation to floating point or integer values.

A full description of the data format is provided in the FAAM Data Github repository. For convenience, a summary of the data format is provided below.

WxRx NetCDF Specification

Global Attributes

• Conventions: CF-1.9 ACDD-1.3

• acknowledgement: Airborne data was obtained using the BAe-146-301 Atmospheric Research Aircraft [ARA] flown by Airtask Ltd and managed by FAAM Airborne Laboratory, jointly operated by UKRI and the University of Leeds

• comment: <str: derived_from_file>

• creator_address: Building 146, Cranfield University, College Road, Cranfield, Bedford. MK43 0AL. UK.

• creator_email: <str: derived_from_file>

• creator_institution: FAAM Airborne Laboratory

• creator_name: <str: derived_from_file>

• creator_type: institution

• date: <str: derived_from_file>

• date_created: <str: derived_from_file>

• flight_date: <str: derived_from_file>

• flight_number: <str: derived_from_file>

• geospatial_bounds: <str: derived_from_file>

• geospatial_bounds_crs: EPSG:4979

• geospatial_lat_min: <float32: derived_from_file>

• geospatial_lat_units: degree_north

• geospatial_lat_max: <float32: derived_from_file>

• geospatial_lon_min: <float32: derived_from_file>

• geospatial_lon_max: <float32: derived_from_file>

• geospatial_lon_units: degree_east

• geospatial_vertical_min: <float32: derived_from_file>

• geospatial_vertical_max: <float32: derived_from_file>

• geospatial_vertical_units: m

• geospatial_vertical_positive: up

• id: <str: derived_from_file>

• institution: FAAM Airborne Laboratory

• keywords: <str: derived_from_file>

• keywords_vocabulary: Global Change Master Directory (GCMD)

• license: UK Government Open Licence agreement - http://www.nationalarchives.gov.uk/doc/open-government-licence

• metadata_link: <str: derived_from_file>

• naming_authority: uk.ac.faam

• platform: FAAM BAe-146-301 Atmospheric Research Aircraft

• platform_type: aircraft

• project: <str: derived_from_file>

• publisher_email: support@ceda.ac.uk

• publisher_institution: CEDA

• publisher_type: institution

• publisher_url: https://www.ceda.ac.uk

• references: <str: derived_from_file>

• revision_date: <str: derived_from_file>

• revision_number: <int32: derived_from_file>

• source: <str: derived_from_file>

• standard_name_vocabulary: <str: derived_from_file>

• summary: <str: derived_from_file>

• time_coverage_duration: <str: derived_from_file>

• time_coverage_start: <str: derived_from_file>

• time_coverage_end: <str: derived_from_file>

• title: <str: derived_from_file>

• uuid: <str: derived_from_file>

• creator_url: https://www.faam.ac.uk

• processing_software_doi: <str: derived_from_file>

• processing_software_url: https://github.com/FAAM-146/faam-wxrx

• processing_software_version: <str: derived_from_file>

• project_acronym: <str: derived_from_file>

• project_name: <str: derived_from_file>

• project_principal_investigator: <str: derived_from_file>

• project_principal_investigator_email: <str: derived_from_file>

• project_principal_investigator_url: <str: derived_from_file>

Dimensions

• time: unlimited

• bins: 512

Variables

• time

  • datatype: <int32>

  • dimensions: time

  • attributes:

    • _FillValue: -9999

    • coverage_content_type: coordinate

    • frequency: 0

    • long_name: Time of scan line estimated from data size

    • units: seconds since 1970-01-01 00:00:00

    • calendar: gregorian

• control_accept

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Control Acceptance Indicator

    • units: 1

    • valid_max: 3

    • valid_min: 0

• slave

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Slave Indicator

    • units: 1

    • comment: 0=Master, 1=Slave

    • valid_max: 1

    • valid_min: 0

• mode_annunciation

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Mode Annunciation, packed

    • units: 1

    • comment: Each bit represents a mode annunciation. See documentation for details.

    • valid_max: 31

    • valid_min: 0

• faults

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Fault Flags, packed

    • units: 1

    • comment: Each bit represents a fault indication. See documentation for details.

    • valid_max: 127

    • valid_min: 0

• stabilization

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Stabilization Indicator

    • units: 1

    • comment: 0=Off, 1=On

    • valid_max: 1

    • valid_min: 0

• operating_mode

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Operating Mode

    • units: 1

    • valid_max: 7

    • valid_min: 0

• tilt

  • datatype: <float32>

  • dimensions: time

  • attributes:

    • _FillValue: -9999.0

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Radar tilt angle

    • units: degree

    • valid_max: 15.75

    • valid_min: -16.0

• gain

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Gain

    • units: dB

    • comment: A value of 0 indicates maximum gain. A value of 1 indicates calibration.

    • valid_max: 1

    • valid_min: -62

• range

  • datatype: <int16>

  • dimensions: time

  • attributes:

    • _FillValue: -9999

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Range from aircraft

    • units: 1

    • comment: Represents the maximum range bin

    • valid_max: 320

    • valid_min: 5

• data_accept

  • datatype: <int8>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Data Accept Indicator

    • units: 1

    • valid_max: 3

    • valid_min: 0

• scan_angle

  • datatype: <float32>

  • dimensions: time

  • attributes:

    • _FillValue: -128

    • coverage_content_type: auxiliaryInformation

    • frequency: 0

    • long_name: Radar Scan Angle

    • units: 1

    • comment: The scan angle is the angle between the aircraft and the center of the radar beam.

    • valid_max: 359.912109375

    • valid_min: 0

• reflectivity

  • datatype: <int8>

  • dimensions: time, bins

  • attributes:

    • _FillValue: -128

    • coverage_content_type: thematicClassification

    • frequency: 0

    • long_name: Categorized reflectivity data

    • units: 1

    • valid_max: 7

    • valid_min: 0