Investigation of Unexpected Sea-States

It is assumed that dangerous and unexpected sea-states may occur if the sea conditions are fairly rough. It is therefore of concern to meteo centers to include sea-state related parameters in marine weather forecast when they exceed a certain threshold. To select appropriate parameters that can point at dangerous wave events, the sea-state at the time and location of shipping accidents reported as being due to bad weather by the Lloyd’s Marine Information Service (LMIS) were extracted from the ECMWF ERA-40 archive. The analysis of these wave parameters reveals the occurrence of apparently rather low sea-states (e.g. H_m0 < 4 m). To test the findings against the related oceanographic features, wave climatology was computed. The present study aims at finding a possible correlation between wave climate and shipping incidents to identify warning criteria.