Mission Based Ship Design Under Uncertain Arctic Sea Ice Conditions

For the design of an ice-going ship, determining its ice-capability is one of the key design aspects. Excessive ice-capability increases the ship’s acquisition cost and reduces its deadweight capacity. On the other hand, less ice-capability limits its serviceable area and it decreases the probability for the ship to complete its given/expected missions successfully. The ice conditions, which the ship would encounter during its operations, are dependent on its route planning, and they become a basis for the determination of its ice-capability. For the design of an ice-going ship, which is going to be operated under constant operational conditions, static route analysis or use of historical voyage data is sufficient to estimate its required ice-capability. However, if the operational conditions change dynamically, like the Arctic sea ice conditions, a dynamic route analysis is needed. Otherwise, the required ice-capability tends to be over-estimated by the static analysis. Sea ice conditions in the Arctic change dynamically from hour-to-hour. In addition, the forecast of its operational conditions has a high uncertainty due to lack of understanding of the Arctic sea ice. Thus, for the design of a ship for Arctic operation, we carry out transit simulations in a dynamic and stochastic manner in this paper and estimate the required ice-capability from the simulations’ result.