Weather Radar pp 235-254 | Cite as

Radar Sensor Synergy for Cloud Studies; Case Study of Water Clouds

  • Herman Russchenberg
  • Reinout Boers
Part of the Physics of Earth and Space Environments book series (EARTH)


Since the middle of the 1990s the use of radar for cloud profiling gained a lot of momentum because of the large need for reliable data to study the role of non-precipitating clouds in the climate system. High-frequency systems especially, for example, at 35 and 94 GHz, corresponding to about 0.9 and 0.3 cm wavelengths, were exploited for their feasibility to measure the structure of non-precipitating clouds. As a result of several experiments and field campaigns, it was soon realised that radar, although very useful, was not sufficient in revealing all the necessary information. It had to be combined with other sensors, like lidars or radiometers. A particular example is the observation of a low-level water cloud. The water droplets at the cloud base are in many cases too small to be detected by radar, and the radar will only measure part of the vertical profile of the cloud. Combination with an optical instrument like a lidar will then fill the gap. The lidar signal, however, is often absorbed before it reaches the cloud top, whereas the radar has no difficulty in observing the cloud particles there. Radar and lidar are in this case truly complementary instruments.


Water Cloud Cloud Droplet Liquid Water Content Cloud Base Drop Size Distribution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Herman Russchenberg
    • 1
  • Reinout Boers
    • 2
  1. 1.Delft University of TechnologyThe Netherlands
  2. 2.Royal Netherlands Meteorological InstituteThe Netherlands

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