The effect of changes in wind strength and wave heights on the safety of vessels in shipping

This article investigates whether changes in oceanographic conditions can be filtered out to measure their effect of the overall safety level of ships. The article is based on a unique dataset of 3.2 million observations from 20,729 individual vessels for the time period 1979 to 2007 in the North Atlantic and Arctic region. It combines ship particular information, ship safety inspections, casualties, ship economic cycles and oceanographic data. Standard econometric models are used to measure whether the effect of significant wave height and wind strength towards the probability of casualty can be measured and tests whether it changed over the time period on hand since changes in oceanographic conditions have been confirmed in the literature for the North Atlantic. The results show that the effect of wind strength and significant wave height can be measured towards the probability of casualty although there is no clear seasonal pattern while overall; the probability of casualty is influenced by seasonality with the winter month showing the highest probability of casualty. With respect to changes over time periods, significant wave height shows an increasing effect in January, March, May and October while wind strength show a decreasing effect over time, especially in January, March and May. The results for significant wave height might be relevant for the policy maker such as the International Maritime Organization (IMO) in the context of developing goal based standards for ship constructions or revising common structural rules used for the design of ships.