International marine and aviation bunker fuel: trends, ranking of countries and comparison with national CO2 emission

During the last 25 years the average global annual increase was about 0.8% for marine bunkers and about 3.3% for aviation emissions. Annual variations of marine bunker fuel use per country are larger than of aviation fuel use, sometimes more than 50%. However, the distinction between fuel use for domestic and international aviation is more difficult to monitor. The dominant fuel in marine bunker fuel consumption is residual fuel oil ('heavy fuel oil'). The share of diesel oil slowly increased from 11% in 1970 to 20% in 1990. Aviation fuels sold are predominantly jet fuel ('jet kerosene'). The small share of aviation petrol is slowly decreasing: from about 4% in 1970 to 1.3% in 1990.

Carbon dioxide emissions from the combustion of international marine bunker fuels and aviation in 1990 contributed globally about 1.8% and 2.4%, respectively, to the total global anthropogenic emissions (excluding deforestation). However, aviation emissions include an unknown percentage for domestic aviation. When compared with total transport emissions, international transport has a share of 20%. For both marine and aviation bunker fuel, the Top-10 of the highest consumer countries account for about two-thirds of the global total; the Top-25 countries already account for 85% or more of the total CO₂ emissions worldwide.