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.

• Direct, diffuse, and total irradiance in 5 spectral bands
• Temporal resolution 15 seconds

• Absolute calibration

Data are available on request, please fill the data request sheet and send it to info@joyce.cloud.

Data quicklooks can be found in the JOYCE quicklook browser.

Example time series of MFRSR spectral irradiances (total, diffuse, and direct) on 6 August 2020 at JOYCE.