A new study by Zero Carbon Analytics finds that emissions from international shipping cost the global economy around USD 963 billion between 1990 and 2020. These economic impacts are projected to worsen with continued emissions growth, if business-as-usual continues, and could outweigh the cost of action to reduce emissions in the sector.

The findings come as governments at the UN’s International Maritime Organization (IMO) resume talks on 23 November on adopting the Net-Zero Framework (NZF), a climate policy to cut emissions from ships. Opposition from some IMO member states has centred on the NZF’s implementation costs, overlooking growing negative impacts of shipping emissions on economies.

Some of the world’s biggest economies suffer the greatest absolute damages from emissions. The study finds that international shipping’s share of global emissions has caused the US USD 280.7 billion in damages, China USD 113.5 billion, and Japan USD 66.8 billion. However, the relative damage caused by emissions tends to be highest in low-income countries and in the Middle East. Damages attributable to international shipping emissions reduced the United Arab Emirates’ 2020 GDP by 0.35%, Saudi Arabia’s by 0.34%, Mali’s by 0.32%, and Burkina Faso’s by 0.3%.

The US and Middle Eastern oil-producing states are leading opponents of the NZF, citing concerns over impacts on trade, while bearing some of the highest costs of inaction on shipping emissions.

Implementing the NZF and reducing emissions would help reduce the impacts of climate change, protecting human health and nature. Implementing and acting on the NZF could avoid approximately 14.2 billion tonnes of CO2-equivalent emissions between 2026 and 2050, compared to business-as-usual. In terms of human impact, the NZF could help avoid an additional 1.5 million heat-related deaths by 2100.

International shipping is responsible for around 2% of annual carbon dioxide emissions globally, which IMO member states agreed must reach net-zero by or around 2050, in line with Paris Agreement goals.

“Improved methods allow us to calculate the economic impact of emissions by connecting emissions to temperature increase, and temperature increase to economic damage. This essentially reveals the ‘hidden’ costs countries are paying for emissions – a missing part of the picture for IMO regulators wanting to agree on the best possible policy. Taking these into account can help countries weigh up the actual costs and benefits of working towards net zero in shipping, although it is important to consider that the real costs of future climate damages could be much higher than currently anticipated.” – Victoria Kalyvas, Senior Research Associate, Zero Carbon Analytics

The IMO is set to continue negotiations on the NZF in a technical group (ISWG-GHG-23) on 23-27 November, before discussing adoption in political negotiations (MEPC 85) on 30 November – 4 December.

2026 09 Shipping emissions have already cost the world almost a trillion dollars in damages