International marine bunker emissions have returned to 1990 levels, mainly because of a large decrease (52 per cent) in marine bunker emissions reported by the United States of America since 1998.
国际海运舱载燃料排放量回落到1990年的水平，主要由于自1998年以来美国报告的海运舱载燃料排放量大幅减少(52%)。