The magnitude of storm-surges varies much for different areas on our planet. In addition, the critical levels depend on the type of coast and the slope of the land near the coast. This makes the absolute surge level of little practical value when studying the impact of storm-surges. The return-period or percentiles provide more insight and relate more directly to the impacts.In this project the aim is to extend a previously developed global Delft3D tide model with wind-forcing. This feature is already implemented in Delft3D, so this is not a programming exercise, though minor changes may be required. With input of the wind and pressure from ERA-40 and/or ERA-interim a consistent set of storm-surges over several decades can be obtained from which the return periods can be computed. Subsequently individual events can be rated on this scale.This project requires Msc level experience in hydrodynamic modeling and experience (or much affinity) with Matlab for post-processing.

During severe storms the sea-level at the tide-gauge of Delfzijl in the northern part of the Netherlands, often shows significant oscillations. These oscillations can add up-to 30cm to the high-water level and current operational hydrodynamic models do not predict these. It is generally believed that these are harbour oscillations, caused by sudden fluctuations in air-pressure and wind-speed associated with an unstable stratosphere or cold-front. Since, these oscillations occur only part of the storm surges, this make prediction of high water very inaccurate at in the Ems. The aim of this project is to study possible oscillations in the Ems estuary with a hydrodynamic Delft3D model. Questions relate to the possible modes of the system and their frequencies. Also the potential to forecast the likelihood of the oscillations to occur for a particular storm is of great practical interest. This project requires Msc level experience in hydrodynamic modeling and some experience (or affinity) with Matlab for post-processing and comparing observations to model results.