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Table of Contents
Broadband radiation
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. For further information about the measurements, please contact B. Bohn
JOYCE-CF Standard Operation Procedures
- Standard measurements of pyranometer and pyrgeometer are performed with 5 second integration time.
Calibrations and data quality assurance procedures
- Regular instrument calibration performed
- Cross-check with other radiation sensors
Data availability
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 data request sheet and send it to info@joyce.cloud.
Dataset | Temporal resolution | File size | Filename | Remarks |
---|---|---|---|---|
Downwelling shortwave irradiance | 5 seconds | 1 file per day (555 KB) | sups_joy_pyrg00_l1_rlds_v01_YYYYMMDDHHMMSS.nc | available via SAMD |
Downwelling longwave irradiance | 5 seconds | 1 file per day (555 KB) | sups_joy_pyrg00_l1_rlds_v01_YYYYMMDDHHMMSS.nc | available via SAMD |
Link to current observations
Data quicklooks can be found in the JOYCE quicklook archive. Attention, quicklooks are only available several days after the measurement.
Measurement examples
History
Period | Place | Project |
---|---|---|
April 2014 - today | Forschungszentrum Jülich | JOYCE |
Total solar irradiance measurements started in 2006, pyrgeometer measurments in 2011, suntracker measurements in 2014.
Technical Specifications
Parameter | Specification | Remark |
---|---|---|
Frequency | 35.5 ± 0.15 GHz | corresponds to wavelength of 8.5 mm |
Peak power (max) | 25 kW | |
Average power | ~ 24 W | |
Pulse width | 200 ns | adjustable (100, 200, or 400 ns) |
Pulse repetition frequency | 5 kHz | adjustable (5-10 kHz) |
Minimum height | 150 m | full sensitivity above 400 m |
Measuring range | 15 km | adjustable (7.5-30 km) |
Range resolution | 30 m | adjustable (15, 30, or 60 m) |
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 | Metek |