Solar radiation is measured in the optical range of the electromagnetic spectrum, beginning in the ultraviolett and ending in the near infrared.Distributions of atmospherical parameters like ozone or other trace gasses, pollutants, clouds and further the influence of the radiance are measured. Our group has developed some instruments by theirself. One exaple for such an instrument is the MUDIS (MUltiDIrectionalSpectrometer) in Picture 1.
With this instrument the spectral radiance from many differerent directions can be measured simultanously. The extraordinary advantages is the high temporal and spectral resolution of the radiance, which was singular when the instrument was developed.
In Addition to the development of new measuring systems new methods of quality control were developed. The aim is, to assure a worldwide comparability of radiation measurements at high quality standards. An important measurment tool is the integrating sphere which contains a homogenious radiation field inside.
The periodic quallity assurance by a calibration of the measurement systems includes a characterisation of the properties of the measurement system and complies the rules of the "Network for the Detection of Atmospheric Composition Change" (NDACC; McKenzie et al., 1997) or the World Meteorological Organisation" (WMO; Seckmeyer et al., 2001). Due to this several measurement comparison campaigns were attended by our group where the equipment was compared with the measurement systems of other international research groups.