The second extensive field campaign targeted to measurements of properties and runup of ship wakes in Tallinn Bay was organized by the wave engineering team on Pikakari Beach on the western coast of the inner part of Tallinn Bay on 12-30 July 2009. A shorter measurement program was also undertaken on the island of Aegna on 1-3 July 2009.
The water surface time series was sampled at a frequency of 5 Hz with the use of a downward-looking echosounder mounted on a rigid tripod approximately 80 m from the coast where the water depth was about 2.7 m. The results were verified by means of a pressure-sensor-based wave recorder mounted on this tripod about 1.5 m under the sea surface. Wave-induced near-bottom currents in shallow water were recorded by two sets of 3D current meters placed at depths of about 0.5 and 1 m and located about 5 m and 15 m from the coast, respectively. These devices were set to record current velocities at 10 cm from seabed.
Wave runup was recorded with the use of a newly constructed capacity-based electronic ruler. This device sampled the position of the waterline at a frequency of 50 Hz. The process of runup was also video-recorded and the maximum runup heights were also observed visually and recorded manually. The beach profiles were recorded before and after each major wave event.
Additionally, the ships were identified manually, their speed and distance to the study site was measured with the use of a laser range finder. Accompanying studies of wave-induced changes of the optical properties of sea water and measurements of bedload and suspended sediment transport were carried out by scientists from the Marine Systems Institute.
The entire team and several guests (prof. Kevin Parnell, Rolf Värv, among others) took part in the planning and organization of the experiment and performing field measurements (which involved more than 70 person-days spent at site).