Multi-purpose platforms for efficient observations in coastal waters

Abstract

The pressure on coastal seas keeps on increasing (navigation, fisheries, tourism, etc.) and this requires robust observations with adequate coverage. The deployment of wind turbines in shallow waters offers a good example demanding high resolution data in the air column, from the free surface to a height of order 200m. The corresponding structural assessment (loads for fixed towers and loads/motions for floating structures) needs also waves/current/sea level data in the upper part of the water column. To address this challenge a prototype buoy, equipped to measure airflow with a LIDAR and water flow with an acoustic Doppler profiler, has been developed and is here presented. The paper shows the conceptual design and performance of this new buoy as a platform for efficient multi-variable observations. The operation of the buoy is based on batteries and solar cells. The resulting observations have been calibrated with data from an instrumented coastal pier during a pilot deployment off the Badalona coast and a meteo mast off the Dutch coast, covering a number of representative met-ocean events.