A new report stresses how slowing the speed of cargo ships could have enormous benefits for humans, nature and the environment.
There are no speed cameras on the high seas. Perhaps there should be. Environmental experts suggest that reducing the speed of commercial shipping is the easiest, quickest and most effective way to mitigate the industry’s impact on global warming.
According to environmental organisation Seas At Risk, just a 20 per cent reduction in ship speed would cut carbon dioxide emissions by 24 per cent, since slower ships burn less fuel. Other benefits include less pollution and less harm to marine mammals.
The shipping industry accounts for between two and three per cent of global human-made emissions. Eventually all shipping will convert to sustainable fuel but, until that day comes, it’s crucial that ocean freight finds some way to reduce its carbon footprint.
Seas at Risk believes it has the answer. In November 2019 it commissioned an in-depth report on the benefits of slower commercial shipping. Here are the key findings:
- Carbon dioxide emissions can be reduced by around 13% and 24%, if ships reduce their speed by 10% and 20% respectively.
- A speed reduction of 10% to 20% would reduce the emissions of nitrogen oxide and sulphur dioxide pollutants by 13% and 24% respectively.
- Soot (or black carbon) emissions from ship engines are another harmful pollutant. “A moderate reduction in speed will lead to reduction in black carbon emissions,” says the report. Soot also increases global warming when it settles on snow and ice in the polar regions since it prevents the reflection of sunlight.
- The noise from ship engines is distressing for marine wildlife. A 10% reduction in speed lowers underwater sound energy by 40%, while a 20% reduction lowers it by 67%.
- On certain ocean routes ships collide with and kill marine mammals. The probability of lethal injury is 50% when vessel speeds are reduced by 10%, dropping to 22% when vessel speeds are reduced by 20%.