Occurrence of Freak Waves in near-coast regions of the North Sea and their potential relationship with objective weather types

Rogue waves are a potential threat for both shipping and offshore structures like wind power stations or oil platforms. While individual Rogue waves are short-lived and almost unpredictable, there is a chance to predict the probability of the occurrence of freak waves in conjunction with different weather types. The German Ministry of Transport and digital Infrastructure has tasked its Network of Experts to investigate the possible evolutions of extreme threats for shipping and offshore wind energy plants in the German Bight, the south-eastern part of the North Sea near the German coast.

In this study, we present an analysis from the co-occurrence of freak waves with different weather types in the German Bight in the past (from observations). In addition, we investigate potential changes of the occurrence of freak waves in the future due to a changing climate and changing appearance of the relevant weather types (by use of a coupled Regional Ocean-Atmosphere Climate Model, MPI-OM).

The investigation indicates a connection between the probability of the occurrence of freak waves at different stations and certain weather types. Potentially, this relationship could be used for warning crews of ships or offshore constructions. In a coupled Regional Ocean-Atmosphere Climate Model (MPI-OM) under scenario RCP8.5 we detect an increase of just such weather types, which are correlated with high waves, for the future.