Small-scale Variability of Clouds

The variability of clouds and its impact on the atmospheric radiation is examined. This variability strongly influences the accuracy of satellite products and the comparability of ground-based and satellite-borne measurements.

Current Research Topics

  • Radiation measurement network: The variability of the atmospheric radiation is observed during extensive campaigns (e.g. HOPE) by a unique mobile measurement network of 100 pyranometer stations. The data allows conclusions about the variability and other statistical properties of small-scale clouds.
  • Mobile observation of aerosol optical properties: With a multispectral radiometer (GUVis-3511) the spectral, downward, global irradiance at 19 wavelengths between 300nm and 1700nm get observed. The applied dynamic shadowband provides a huge increase of functionality for the radiometer. Thus one can split the downward global irradiance in its direct and diffuse part and observe optical properties of aerosol in the atmosphere with a single sensor.
  • Influence of small-scale variability at radiation effects in clouds: The effect of the small-scale variability at the atmospheric radiation budget get observed by a combination of ground-based and satellite-borne measurements of clouds and radiation. At the foreground stands the quantization of the uncertainties of radiation effects in clouds at bottom and TOA.
  • Radiation enhancement: With high-quality pyranometers and photometer with high temporal resolution the global irradiance get observed. An all-sky camera provides pictures of the whole sky every 15 seconds. This measurements were performed long-time. In dependence of cloud-type, radiation geometry and meteorological influence, the radiation enhancement due to clouds get observed.