SEMINAR: OI Seminar Series - Ulrich Flachsenberger

Title: Origin of offshore Infra-gravity Waves during Storm Events, Geographe Bay, South-West Australia Abstract: Due to their long wave character, infra-gravity waves are found to be responsible for many different phenomena in coastal zones. Within harbours, long waves became apparent as the primary factor to determine the intensity of horizontal water motions. Especially when a harbour basin is periodically forced at its resonance frequency, large oscillations inside the harbour can be produced. Certain harbours worldwide including the harbours of Geraldton, Two Rocks, Bunbury and Esperance along the south and west coasts of Western Australia experience harbour oscillation problems. Such harbours are affected by unacceptable ship movements through to damages at the system vessel-mooring-berth what finally poses a lack of reliability for harbour operations and its facilities [RABINOVICH, 2009]. Infra-gravity waves also influence sand transport processes on beaches (KULARATNE and PATTIARATCHI, 2006) The current state of research is that infra-gravity waves are usually generated by groups of waves traveling shorewards. However, the source of infra-gravity waves is not well understood, although some might be generated during storm events [HOLTHUIJSEN, 2007]. In particular this Research should respond to the following key questions: When does infra-gravity waves do occur at Geographe Bay? What can be seen as the origin of these long waves? What major correlations can be found in this context?

CV brief: Ulrich holds the degree of civil engineering/University of applied Science Coburg. After working for consulting engineers and a coastal protection administration he joined University of Rostock for a Master course focusing on Coastal Engineering. Ulrich's general interests are in the field of waves.