Manya Rathore
Research expert covering India
Shipping emissions worldwide - statistics & facts
The global maritime shipping industry was responsible for around two percent of global greenhouse gas emissions (GHG) in 2023. With emissions from this hard-to-abate sector continuing to grow, the industry is now under increasing pressure to decarbonize. But with shipping still heavily reliant on fossil fuels, particularly heavy fuel oil (HFO), significant transformations will be required if the sector is to achieve its goal of net zero by 2050.
The maritime industry is actively pursuing strategies to reduce its impact on the climate. But with fossil fuels still accounting for some 90 percent of the sector’s fuel mix and less than one percent of total global energy transition investment going toward clean shipping in 2024, the sector is currently not on track to achieve net zero by 2050.
Emissions from international shipping
The global volume of seaborne trade more than tripled between 1990 and 2023, to over 12 billion tons loaded. This surge in commerce saw carbon dioxide emissions from international shipping rise some 90 percent during this period, to more than 700 million metric tons (MtCO₂) annually. But GHGs aren’t the only atmospheric pollution linked to shipping. The maritime industry is also a major source of toxic air pollutants, including nitrogen oxides (NOx) and sulfur dioxide (SO2). Nevertheless, SO2 emissions from international shipping have plummeted more than 70 percent since 2019 as a result of the International Maritime Organization (IMO) introducing new regulations on sulfur content in marine fuels.What are the most polluting vessels?
The world’s merchant fleet is made up of many different types of vessels, all of which are significant GHG emitters. The biggest contributors to shipping emissions, though, are container ships. These vessels emit over 200 MtCO2 every year, and make up more than a quarter of annual shipping CO₂ emissions. Climate pollution from these vessels is expected to have soared even further in 2024 as a result of the Red Sea crisis, which has resulted in significant rerouting of maritime traffic around the southern tip of Africa. Emissions from container shipping in the European Union alone are estimated to have risen almost 50 percent year-on-year, with diversions playing a significant role in this increase.Decarbonizing the shipping industry
International Maritime Organization member states have agreed to reach net zero emissions from international shipping by or around mid-century. Alternative fuels like ammonia and hydrogen are considered two of the main decarbonization levers going forward, while the increased adoption of innovative green shipping technology solutions, like high-tech automated wing sails, is also expected to play key roles in mitigation efforts. However, decarbonizing the shipping industry will require substantial investment, with estimates of almost three trillion U.S. dollars needed between 2023 and mid-century.The maritime industry is actively pursuing strategies to reduce its impact on the climate. But with fossil fuels still accounting for some 90 percent of the sector’s fuel mix and less than one percent of total global energy transition investment going toward clean shipping in 2024, the sector is currently not on track to achieve net zero by 2050.
