Cut In Pollution From Shipping 'Doubled The Rate Of Global Heating'

The slashing of pollution from shipping in 2020 led to a big "termination shock" that is estimated to have doubled the rate of global heating compared with the long-term average, according to research.

- Damian Carrington

Until 2020, ships used dirty, high-sulphur fuels that produced air pollution. The pollution particles blocked sunlight and helped form more clouds, thereby curbing global heating. But new regulations at the start of 2020 cut the sulphur content of fuels by more than 80%.

The new analysis calculates that the subsequent drop in pollution particles has significantly increased the amount of heat being trapped at the Earth's surface that drives the climate crisis. The researchers said the sudden ending of decades of shipping pollution inadvertently created a geoengineering experiment, revealing new information about its effectiveness and risks.

High ocean surface temperatures smashed records in 2023, alarming experts who have struggled to explain the huge rises. But scientists have mixed views on the role played by the cut in shipping pollution.

Authors of the study say it could be a "pretty substantial" factor. Others say it is only a small factor, and the reasons for the rises in sea and global temperatures remain a mystery.