Oceanographic monitoring network in the Danish waters

Abstract

The Royal Danish Administration of Navigation and Hydrography (RDANH) is the organisation responsible for navigational safety in the Danish, Faroese and Greenlandic waters. For many years this responsibility has implied: u * hydrographic surveying * establishment and maintainance of lighthouses and buoys for shipping guidance * operation of various radio navigation systems such as Decca, Sylidis, Loran-C and recently DGPS * piloting * organisation of the coastal rescue service In 1990 an additional activity was added with the establishment of a Physical Oceanographic Department responsible for the collection, analysis and distribution of oceanographic data. This activity serves two purposes: firstly to support the Hydrographic Surveying Department with oceanographic data (water level, currents and sound velocity profiles) needed for quality control of their data and secondly to improve the navigational safety in the Danish waters by communicating real time data on water level, current velocity and direction, waves, buoyancy and wind speed and direction. A network of 13 stations water level stations were established in 1991. Measurements are performed every 15 minutes with realtime and data transfer to the cental storage database in Copenhagen via the public data network. In 1995 and early 1996 six oceanographic stations have been established. These stations are equipped to measure current velocity and direction at six depth levels, wind speed and direction and the vertical distribution of temperature and salinity in the water column. The measuring interval is 30 minutes with realtime data transfer to the database. The oceanographic data stored in the database are subsequently quality controlled and can be accessed for other tasks such as environmental monitoring, scientific research, construction work. The oceanographic data are communicated to navigators by the personnel manning the Drogden Lighthouse and the Great Belt and Drogden Vessel Traffic System (VTS) centers. In 1996 the RDANH has also established a Recorded Information Service with the purpose of, serving recreational mariners with oceanographic data. The RDANH has received positive feedback from commercial as well as recreational mariners, regarding the operational, oceanographic service, who are all very satisfied with the availiability of real time data on the oceanographic conditions. The next logical task will be to establish a prediction model of the oceanographic conditions in the Danish Straits. To fulfill this task the RDANH has joined a modellign group established under HELCOM.