First Paragraph
Oceanographic research using HF radar techniques started in Germany in 1980 by adopting NOAA’s CODAR (Coastal Ocean Dynamics Applications Radar), which has originally been introduced by Barrick et al. in 1977. In Germany, the CODAR has been modified and used during several experiments since 1981. From 1985 to 1992, the University of Hamburg CODAR has been extended for shipborne operation. The first experiment has been carried out on board the German icebreaker Polarstern, which most of the time has been sailing within the ice, far away from open water. The main result of this experiment was that the attenuation of ice-covered sea reduces the performance and working range extremely. Good measurements have only been possible with the ship sailing at the ice edge or in open water. However, this application did not need an icebreaker, so the following experiments have been carried out using the University of Hamburg R/V Valdivia.