Paper presented at the 28th Arctic and Marine Oilspill Program (AMOP) Technical Seminar, 7-9 June 2005, Calgary, Canada
The number of oil spills from tanker ships has decreased significantly over the last 30 years. In fact the average number of spills per annum in the 1970s was approximately 3 times that for the 80s and 90s and more than 6 times the number so far for this decade. This is despite a steady increase in seaborne oil trade since 1985. This paper examines trends in tanker oil spills worldwide over the 10 year period from 1995 to 2004 and analyses potential influences on spill volumes and frequencies for incidents of 3 different spill size classes. Factors that are used to identify trends include: Causes i.e. the primary operation or accidental event in progress at the time of the incident; location in terms of the countries where spills frequently occur; oil type (crude, bunkers, fuel cargo, white products); shipping legislations. It is difficult to identify any one factor which contributes to the decline in overall volume and frequency of spills, rather it is considered to be the result of a range of initiatives taken by governments and the shipping industry.