Currently, international shipping emissions make up about 2 to 3 percent of global emissions of greenhouse gases, including carbon dioxide and methane. (sciencenews.org)
The IMO's most recent study on international shipping emissions estimated they could grow between 50 % and 250 % by 2050, under current measures. (carbonbrief.org)
This includes the UK's share of international shipping emissions and an allowance for aviation, which remains outside this budget but must fall within the 2050 goal. (carbonbrief.org)