The Cryogenic Solar Absolute Radiometer (CSAR) along with the Monitor to Measure the Integral Transmittance of Windows (MITRA) is expected to become the new World Radiometeric Reference (WRR) for . . .

The Precision Spectroradiometer (PSR) has been developed to eventually replace current filter based sun-photometers. A continuous measurement range of 320-1040 nm, allows AOD and trace gas values to be determined.

Infrared Integrating Sphere Radiometer (IRIS) has been developed as a new reference radiometer to measure downward longwave irradiance. IRIS is calibrated relative to the PMOD/WRC blackbody cavity . . .

A second generation of Precision Filter Radiometers (PFR) was developed at PMOD/WRC to secure the continuous operation of the GAW-PFR and other networks for the foreseeable future.

The growing interest in night-time observ-ations of AOD has led to the development of a lunar Precision Filter Radiometer (PFR) at PMOD/WRC. In addition to the retrieval of nocturnal AOD . . .

One of the main objectives of the European Brewer Network (EUBREWNET; COST Action ES1207) is the retrieval of AOD in the UV spectral range. A UV PFR has been developed by PMOD/WRC and . . .