High-resolution radar wave and current measurements in highly inhomogeneous coastal areas

Coastal waters are characterised by complex wave fields that are influenced by inhomogeneous bathymetries, and changing tidal and wind induced currents. The understanding of these interactions has gained more interest over the last years especially for port entrances and close to shore shipping activities. In contrast to in-situ measurements, remote sensing techniques have the advantage to provide area covering data of several parameters (waves, currents and bathymetry), observed at the same time. The wave and current monitoring system WaMoS II is a remote sensing system based on a nautical X-Band radar generally used for navigation and ship traffic control. Nautical radar are designed to monitor the sea surface continuously over a relative large area (~ 10km2 ) with high spatial (~7.5m) and temporal resolution (~2s). In recent years more focus was put on retrieving current and wave data at that high resolution on an operational basis. In this paper a brief introduction into the high resolution current and water depth measurement principle of WaMoS II will be given. A data comparison will be shown from the South Coast of New Zealand. This site is characterised by strong prevailing tidal currents as well as very inhomogeneous, wave and current fields.