The Paris climate agreement, signed in 2015, has a big hole. Emissions from international shipping and aviation, by law, do not come under any country’s jurisdiction. That means, unless the shipping and aviation industries get involved, there’s no way to keep climate change in check.
In April 2018, the International Maritime Organization (IMO), which regulates shipping on the high seas, laid out plans to cut emissions from the sector by 50% by 2050, when compared with 2008 levels. To get there, the IMO is considering new rules for the shipping industry, including putting speed limits on ships.
Controlling a car’s speed and acceleration can improve its fuel efficiency. The same is true with ships. Following the 2008 financial crisis, cargo ships slowed down to deal with lower trade volumes and cut costs. A 12% reduction in at-sea average speed, known as “slow steaming,” led to an average reduction of 27% in daily fuel consumption and thus fewer greenhouse-gas emissions.
Today, an open letter signed by the chief executives of 107 shipping companies, including some of the world’s largest like Euronav, the world’s largest listed crude oil tanker company, and French industrial giant Louis Dreyfus Armateurs, came out in support of the proposal to slow down ships to cut carbon emissions. “Effectively addressing climate change is possibly the greatest challenge of our time,” the letter said. “The signatories to this letter unite in stressing the urgent need for shipping to make its appropriate contribution.”
The IMO’s Marine Environment Protection Committee is due to meet later this month in London. It needs to start working on the details of regulations, which would need to be adopted as early as 2020 to put the shipping industry on the track to cut emissions in a meaningful way. (In addition to addressing carbon emissions, the IMO has set out rules to cut the sulfur content of shipping fuels, which will reduce smog-causing pollution.)
“Ships are speeding up again as global demand recovers,” said the execs in the letter. “Should this trend continue, any [greenhouse gas] gains from slow steaming over recent years will disappear.”
What about the effect on trade? It turns out that slower-moving ships won’t have a significant impact, as fewer ships using more of their carrying capacity can meet rising demand for cargo transport. A study (pdf) conducted by the consultancy CE Delft found that cutting ship speeds by 30% reduces the GDP of exporting countries by less than 0.1%.
Lower speeds alone, however, will not be enough to cut shipping emissions in line with the Paris climate agreement. The IMO will also have to find ways of encouraging the use of low-carbon fuels, like natural gas, or zero-carbon options like hydrogen, if it is to meet its 2050 climate goals.
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