Multi-Filter Rotating Shadowband Radiometer (MFRSR)
MFRSR installed at Jülich
The Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at one broadband channel and at six narrowband channels, i. e. at 415, 500, 615, 673, 870, and 940 nm. Direct irradiance is subsequently calculated from the diffuse and global measured components. Each MFRSR measurement sequence includes measurements at four different shadowband positions: 1) at nadir (home position), 2) at the first side-band position, 3) sun-blocked, 4) at the second side-band position. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. From the MFRSR measurements, the aerosol optical depth at the wavelengths 415, 500, 615, 673 and 870 nm as well as the Angstrom exponent can be derived. For single-layer “horizontally homogeneous” liquid clouds, layer cloud optical depth and effective radius can also be retrieved.
JOYCE-CF Standard Operation Procedures
Direct, diffuse, and total irradiance in 5 spectral bands
Temporal resolution 15 seconds
Calibration and data quality control
Data are available on request, please fill the data request sheet and send it to email@example.com.
| Dataset || Temporal resolution || File size || Filename || Remarks
| Radiances || 15 seconds || 1 file per day (~1.5 MB) || DayYYYYMMDD.txt ||
Link to current observations
Example time series of MFRSR spectral irradiances (total, diffuse, and direct) on 6 August 2020 at JOYCE.
| Parameter || Specification
| Wavelengths || Silicon broadband pyranometer, 415, 500, 615, 673, 870, 940 nm
| FWHM bandwidth || 10 nm
| Cosine response || Better than 5% for 0 - 80° zenith angle; better than 1% with corrections
| Temporal Resolution || 15 s
| Weight || 4.55 kg
| Power Consumption || 110/220 VAC, 50/60 Hz (50 watts maximum)
| Manufacturer || YES Inc.