ABSTRACT
The Baltic Sea is composed by 7 zones: Bay of Bothnia, Sea of Bothnia, Gulf of Finland, Gulf of Riga, Central Baltic, South Baltic (coast line), and Western Baltic (Danish waters) (EfficienSea, 2011). All these zones experience different weather and light conditions during winter time. For example, the northern area (Bay of Bothnia) have long periods of darkness, and heavy winter storms which represent the first challenges for the vessels navigating the zone before sea ice is present in the area. In other areas such as central Baltic, Gulf of Finland and South and Western Baltic, the light conditions are not as drastic as in the north, but in these areas, during winter the vessels have to deal with heavy banks of fog constantly (Trafi, 2011). Once the ice is present, the Bay of Bothnia is commonly the first zone which set traffic restrictions during winter. These restrictions specify which are the merchant vessels allowed to navigate the area,
1 INTRODUCTION
Collisions and groundings are the most common accidents in the Baltic Sea, including winter season with or without the presence of ice (Goerlandt, et al., 2012). Even though some specific areas within the Baltic Sea are recognize as relative safe (e.g. the Gulf of Finland), every year approximately 22 to 34 accidents occur in this zone (Kujala, et al., 2009). The collisions and groundings reported are commonly related to human failures which endanger people, environment and the whole transportation system. In the most severe cases these accidents may lead to severe damage (e.g. to the ship structure), compromising ship’s integrity, and exposing people and environment to human casualties and cargo spills. In less serious cases, these accidents may result in only small damages to the hull (Kujala, et al., 2007, Kujala, et al., 2009 and Mazaheri, et al., 2013).
