While many were disappointed by the lack of major breakthroughs at COP26, the recent U.N. climate talks, significant progress was made in beginning to clean up shipping emissions on global trade routes.

As reported by the Washington Post, the United States, Japan, Germany, Britain, France, and others — 22 countries in all — signed the Clydebank Declaration for Green Shipping Corridors, a new framework for reducing carbon dioxide and other greenhouse gas emissions from shipping. The signatories commit to establishing “zero-emission maritime routes” for ships using clean marine fuels such as methanol or ammonia.

They plan to establish six of these green corridors by 2025 and scale up further by “supporting the establishment of more routes, longer routes and/or having more ships on the same routes,” according to the declaration.

Jan Stockbruegger writing in the Washington Post comments that the Clydebank declaration is far from perfect. The declaration is not a binding treaty, and it lacks compliance mechanisms and clear investment and energy-reduction targets.

Yet environmental organizations view this announcement as a major milestone for the decarbonization of the maritime industry. Dan Hubbell of Ocean Conservancy notes that the declaration “will help pave the way for eliminating emissions from ports and shipping here in the U.S. and internationally.”

The signatory countries will cooperate with the marine industry to invest in clean port infrastructure and to set up comprehensive programs for green shipping activities. They will also develop regulatory frameworks and incentives to mobilize demand for zero-emission vessels on specific routes. This includes the Asia-Europe container route, which currently generates more emissions than any other shipping route. The hope is that green shipping corridors will then create spillover effects and help catalyze the decarbonization of global maritime supply chains.

Shipping is the most fuel-efficient means of global transportation, but the sector also contributes roughly 3% or 1,056 million tons of greenhouse gas (GHG) emissions annually – a figure that rivals the emissions of Germany.