The TRR 181 seminar is held by Dr. Yaron Toledo (Tel-Aviv University) on
Infra-gravity waves generation and evolution - an attempt to acquire a more wholesome understanding from theoretical, modelling and field measurements perspectives
at Universität Hamburg, on January 27 at 11 am, Bundesstr. 53, Room 002 (ground floor).
Infra-gravity waves are waves that lie outside of the wind-wave spectral regime. They are related to longer wave periods of few tens to few hundreds of seconds. Even though their wave heights are an order of magnitude lower than the ones in the wind wave spectral peak, their comparably large wavelengths (O(1-10km) depending on the bottom depth) can largely influence marine conditions due to basin resonances, harbor agitations and their influence on beach morphology. Infra-gravity waves are too long to be generated directly by the wind (hence their name) and are currently believed to be generated solely via triad interactions as part of the nonlinear wave shoaling process in the near-shore region.
An on-going investigation of infra-gravity waves will be discussed and inspected in a wholesome manner combining theoretical, modelling and field campaign perspectives. It will describe a new physical mechanism for their nonlinear generation in deep water, and their linear and nonlinear shoaling processes on the continental shelf, and on the near-shore region. A multi-instrument field campaign (using ADCPs, a wave buoy, pressure gauges, wave staves and an X-band radar) for investigating their evolution will also be discussed. The campaign combines measurements in the Levantine basin off the continental shelf, right outside Haifa bay, inside the bay and within the Haifa port. The campaign's plan will be presented and some preliminary results will be discussed.