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Cloud radar JOYRAD-35

Cloud radar JOYRAD-35 installed at Jülich

Principle

JOYRAD-35 is a scanning Doppler cloud radar MIRA-35 manufactured by METEK GmbH. It is installed at the Forschungszentrum Jülich as part of JOYCE. The radar transmits a linearly polarized signal at 35.5 GHz (Ka-Band) and receives co- and cross-polarized signals simultaneously. In this way, vertical profiles of reflectivity, Doppler velocity, Doppler spectral width and of linear depolarization ratio are detected from 150 m to 15 km above ground. Given these measurements, information on the macrophysical (cloud boundaries, type of cloud particles) and microphysical (e.g., liquid and ice water content) properties of the detected cloud can be derived. The radar has full 3D-scanning possibilities for the entire upper hemisphere.

Measurement modes

Vertically pointing observations with integration times up to 1 seconds.
Full azimuth/elevation scanning capability for horizontal variability of clouds as well as 3D wind vectors in clouds

JOYCE-CF Standard Operation Procedures

Standard measurement mode is vertically pointing, 2 second integration time
Every 30 minutes one azimuth scan at 83° elevation angle with 6° azimuth resolution (duration ~2 minutes) for horizontal wind within clouds and the boundary layer (if sufficient insects are present)

Calibrations and data quality assurance procedures

Check with co-located disdrometer to find out reflectivity offsets
Consistency check with other cloud radars

Data availability

Some of the following data products are provided via Cloudnet ACTRIS cloudnet website with a temporal resolution of 30 seconds. If you would like to have additional data with better resolution or raw Doppler spectra please fill the data request sheet and send it to info@joyce.cloud

Dataset	Temporal resolution	File size	Filename	Remarks
Radar reflectivity factor	30 seconds	1 file per day (30-50 MB)	YYYYMMDD_juelich_categorize.nc	available via Cloudnet
Doppler velocity	30 seconds	1 file per day (30-50 MB)	YYYYMMDD_juelich_categorize.nc	available via Cloudnet
Spectral width	30 seconds	1 file per day (30-50 MB)	YYYYMMDD_juelich_categorize.nc	available via Cloudnet
Linear depolarization ratio	30 seconds	1 file per day (30-50 MB)	YYYYMMDD_juelich_categorize.nc	available via Cloudnet
Profiles of horizontal wind	30 minutes	1 file per day (30-50 MB)	YYYYMMDD_joyrad35_wind_profile.nc
Radar moments	2 seconds	variable size (up to 30 MB/hour in case of thick clouds)	YYYYMMDD_HHMM.mmclx.gz	zipped NetCDF file
Doppler spectra, Radar moments	2 seconds	variable size (up to 2 GB/hour in case of thick clouds)	YYYYMMDD_HHMM.znc	NetCDF file
Doppler spectra	2 seconds	variable size (up to 1 GB/hour in case of thick clouds)	YYYYMMDD_HHMM.zspc	Binary file

Composite products using data from JOYRAD-35

Dual-wavelength ratio Ka/X-Band and Ka/W-Band Link to Quicklooks
Cloudnet target classification uses Radar moments data from JOYRAD-35. Combined with microwave radiometer and ceilometer observation, clouds are characterized by their geometrical extent as well as their microphysical properties. Link to Cloudnet

Link to current observations

Data quicklooks can be found in the JOYCE quicklook archive and in the METEK archive

Measurement examples

Example time series of JOYRAD-35 observations (radar moments / horizontal wind)

Example time series of Cloudnet target classification

JOYRAD-35 History

Period	Place	Project
2017		Instrument upgrade
09/03/2012 - today	Research Center Jülich, Germany	JOYCE
08/11/2011 - 08/03/2012	Munich Airport, Germany	iPort campaign
03/2011 - 07/11/2011	Research Center Jülich, Germany	JOYCE