Ahead of a big green meeting at the International Maritime Organization next week, John Maggs from the Clean Shipping Coalition writes on how getting a global fuel standard and levy over the line will set us up for the future. The international shipping sector provides an outsized and growing contribution to the climate crisis. Slower, more efficient ships can help slash climate emissions, but this will not happen without ambitious regulation. Fortunately, the International Maritime Organization’s (IMO) current revision of the rules around its Carbon Intensity Indicator, a metric for measuring and regulating ships’ carbon emissions provides such an opportunity. Governments are consulting and reviewing evidence on barriers to efficiency and potential solutions, with a final decision on improving the indicator due by January 1 2026. If properly designed, these new rules could address almost half of shipping’s climate impacts and deliver massive ocean health co-benefits. But the outcome is far from certain. The scope of the problem The vast majority of internationally traded goods travel by ship, and these massive ships burn a lot of fuel. As a result, the shipping industry generates around three per cent of all climate emissions globally—a contribution equivalent to that of the whole economy of a country like Germany or Japan. Ships also undermine ocean health. I am not just talking about the environmental harm caused by oil spills when a tanker runs aground or sinks. As we have seen recently in the Black Sea this remains a very serious problem, but ships are also responsible for a myriad of other routine yet damaging operational practices—some legal, some not—that threaten ocean wildlife: oil and chemical discharges, toxic paint coatings, underwater noise pollution, sewage and grey water discharges, and the dumping of plastics, to name just a few. Human health is also threatened, with an estimated 250,000 deaths and millions of childhood asthma cases annually caused by toxic air pollution from fossil-fuel powered shipping. In all these areas, regulation has failed to keep up with the growth of the industry. Sporadic and weak measures mean the problem keeps getting worse. Turning the page? The Carbon Intensity Indicator revision provides the IMO with an important opportunity to address both the climate and ocean health impacts of global shipping and turn the tide on some of these problems. By far the most effective way to reduce ship climate impacts is to slow ships down. A ten per cent speed reduction can lower the emissions of an individual ship’s journey by almost 20%. Even though this will mean, in some cases, using additional ships, there are still large net emission reduction benefits. What’s more, slowing ships down can happen immediately—we don’t need new technology just to take our foot off the gas pedal. We must also look at wind power. In a case of “back to the future,” new high-tech sails can dramatically reduce fuel burn (and thus emissions) on existing ships, and can go even further when new ships are designed from scratch to use wind as their primary means of propulsion. No other transport mode can harness wind power directly in this way – it is shipping’s climate crisis superpower. Most underwater noise pollution is caused by ship propellers, compromising the ability of whales and other marine life to forage and reproduce. Using sails and slowing ships down has a dramatic effect on noise levels, and slower ships are also l