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radiation [2020/08/31 15:23] – [Principle] bpospichradiation [2021/03/01 11:19] (current) – [Link to current observations] bpospich
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 ===== Principle ===== ===== Principle =====
  
-Two pyranometers (CMP 21), a pyrheliometer (CHP 1) and a pyrgeometer (CGR 4) are used to measure solar shortwave radiation and terrestrial longwave radiation. One pyranometer receives total downward solar irradiance. The other instruments are mounted on a suntracker (SOLYS 2) measuring diffuse downward solar irradiance (shaded pyranometer), direct solar irradiance (pyrheliometer) and terrestrial downward irradiance (shaded pyrgeometer). All instruments were produced and calibrated by Kipp&Zonen B.V., Netherlands.   +Two pyranometers (CMP 21), a pyrheliometer (CHP 1) and a pyrgeometer (CGR 4) are used to measure solar shortwave radiation and terrestrial longwave radiation. One pyranometer receives total downward solar irradiance. The other instruments are mounted on a suntracker (SOLYS 2) measuring diffuse downward solar irradiance (shaded pyranometer), direct solar irradiance (pyrheliometer) and terrestrial downward irradiance (shaded pyrgeometer). All instruments were produced and calibrated by Kipp&Zonen B.V., Netherlands. For further information about the measurements, please contact [[https://www.fz-juelich.de/SharedDocs/Personen/IEK/IEK-8/DE/PhotochemieUndRadikale/bohn_birger.html?|B. Bohn]]
  
-===== 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 ===== ===== JOYCE-CF Standard Operation Procedures =====
  
-  * Standard measurement mode is vertically pointing, 2 second integration time  +  * Standard measurements of pyranometer and pyrgeometer are performed with 5 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 ===== ===== Calibrations and data quality assurance procedures =====
-  * Check with co-located disdrometer to find out reflectivity offsets +  * Regular instrument calibration performed 
-  * Consistency check with other cloud radars+  * Cross-check with other radiation sensors
  
 ===== Data availability ===== ===== Data availability =====
  
-Some of the following data products are provided via Cloudnet [[https://cloudnet.fmi.fi/|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 {{ :joyce_data_request_form.pdf |data request sheet}} and send it to [[mailto:info@joyce.cloud|info@joyce.cloud]]+The following data products are provided via the SAMD database. If you would like to have additional data or recent data that have not been uploaded to SAMD yet, please fill the {{ :joyce_data_request_form.pdf |data request sheet}} and send it to [[mailto:info@joyce.cloud|info@joyce.cloud]].  
    
 ^ Dataset     ^ Temporal resolution       ^ File size          ^ Filename   ^ Remarks    ^ 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   | +Downwelling shortwave irradiance   | seconds    | 1 file per day (555 KB)     | //sups_joy_pyr00_l1_rlds_v01_YYYYMMDDHHMMSS.nc//  | available via SAMD   | 
-Doppler velocity   | 30 seconds    | 1 file per day (30-50 MB)     | //YYYYMMDD_juelich_categorize.nc//  | available via Cloudnet   | +Downwelling longwave irradiance   | seconds    | 1 file per day (555 KB)     | //sups_joy_pyrg00_l1_rlds_v01_YYYYMMDDHHMMSS.nc//  | available via SAMD   | 
-| 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 [[http://gop.meteo.uni-koeln.de/~Hatpro/dataBrowser/dataBrowser2.html?site=TRIPEX-pol&date=-1&UpperLeft=3radar_Ze&UpperRight=3radar_DWR|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. [[http://devcloudnet.fmi.fi/|Link to Cloudnet]] 
  
 ===== Link to current observations ===== ===== Link to current observations =====
  
-Data quicklooks can be found in the [[http://gop.meteo.uni-koeln.de/~hatpro/dataBrowser/dataBrowser2.html?site=JOYCE&date=-1&UpperLeft=Joyrad35_Overview&UpperRight=Joyrad35_wind_ppi|JOYCE quicklook archive]] and in the [[https://guest.metek.de/skripts/animate_hourly_xcrl_skew.html?nic=juel|METEK archive]]+Data quicklooks can be found in the [[http://atmos.meteo.uni-koeln.de/~hatpro/dataBrowser/dataBrowser1.html?site=JOYCE&date=-31&UpperLeft=Radiation_downwelling_fluxes|JOYCE quicklook archive]]. Attention, quicklooks are only available several days after the measurement
  
 ===== Measurement examples ===== ===== Measurement examples =====
  
-{{wiki:examples:200704_jue_l2_radar.png?direct&400|JOYRAD-35_obs}} +{{wiki:examples:20190804_jue_radiation_v00.png?direct&600|Radiation_obs}}
-{{wiki:examples:20200704_joyrad35_wind_profile.png?direct&400|JOYRAD-35_wind}} \\ +
-//Example time series of JOYRAD-35 observations (radar moments / horizontal wind)//+
  
  
  
-{{wiki:examples:20200704_juelich_classification.png?direct&800|Cloudnet_target_classification}} \\ 
-//Example time series of Cloudnet target classification// 
  
- +=====  History =====
- +
-===== JOYRAD-35 History =====+
 ^  Period  ^  Place  ^  Project  ^ ^  Period  ^  Place  ^  Project  ^
-| 2017 |  |  Instrument upgrade | +|  April 2014 - today | Forschungszentrum Jülich | JOYCE |
-| 09/03/2012 - today | [[http://www.fz-juelich.de/|Research Center Jülich]], Germany | JOYCE | +
-| 08/11/2011 - 08/03/2012 | Munich Airport, Germany| iPort campaign | +
-| 03/2011 - 07/11/2011 | [[http://www.fz-juelich.de/|Research Center Jülich]], Germany | JOYCE |+
  
- +Total solar irradiance measurements started in 2006, pyrgeometer measurments in 2011, suntracker measurements in 2014.
-{{:wiki:instruments:joyrad35_07.jpg?direct&600|JOYRAD-35 ©B. Pospichal}} \\ +
-//Cloud radar JOYRAD-35 installed at Jülich//+
  
  
  
 ===== Technical Specifications ===== ===== Technical Specifications =====
-^ Parameter  ^ Specification  ^ Remark + 
-Frequency | 35.5 ± 0.15 GHz  | corresponds to wavelength of 8.5 mm | + Parameter  Specification  Remark 
-Peak power (max) | 25 kW  |  +Total solar irradiance (CMP 21)Secondary standard (WMO)| | 
-Average power | ~ 24 W |  | +Diffuse solar irradiance (CMP 21)| Secondary standard (WMO)| shaded 
-| Pulse width | 200 ns | adjustable (100, 200, or 400 ns | +Direct solar irradiance (CHP 1)| First class (WMO)| tracked 
-| Pulse repetition frequency | 5 kHz adjustable (5-10 kHz) | +Terrestrial irradiance (CGR 4)| Certified calibration shaded 
-| Minimum height | 150 m | full sensitivity above 400 m  +Manufacturer Kipp & Zonen B.V., NL | | 
-Measuring range | 15 km | adjustable (7.5-30 km | +Data logger (CR3000)| 16-bit 5 s time resolution 
-| Range resolution | 30 m adjustable (15, 30, or 60 m) | +| Manufacturer | Campbell Scientific Inc., UK 
-| Antenna beam width | 0.6° | +
-Doppler velocity resolution | 0.025 m/s | depends on FFT length | +
-| Maximum unambiguous velocity | ±20 m/s |  | +
-| Maximum sensitivity at 5 km (integration 0.1 s) | -45 dBZ  +
-Calibration system accuracy ±0.5 dB  +
-Number of gates (with simultaneous stored raw data) | 500  | +
-| Number of averaging spectra | 200 | adjustable (1-32768) +
-| Manufacturer | [[http://www.metek.de/|Metek]] |  +
-                                    |+
radiation.1598880188.txt.gz · Last modified: 2020/08/31 15:23 by bpospich