New Science paper outlines climate coalition

Heavy industries such as steel, aluminum, cement and fertilizer produce the materials on which modern economies depend. They also produce roughly one-fifth of global greenhouse gas emissions. Yet countries often hesitate to make these industries pay for their pollution, fearing that production and jobs will move abroad.

A new paper in Science by researchers affiliated with the Global Climate Policy Project at Harvard and MIT proposes a novel solution: a climate coalition in which willing countries set minimum carbon prices for these four sectors and charge comparable fees on imports from countries outside the group. Lower-income members could begin with lower prices and receive financing and technical support, making participation fairer and more politically feasible.

Using plant-level data and a global trade model, the authors estimate that an initial coalition of advanced and emerging economies could cut annual emissions by about 750 million metric tons of carbon dioxide equivalent – roughly 1.5 percent of all global greenhouse gas emissions. These are near-term gains based on cooperation, not on unproven technology. Output in member economies would fall by just 2 percent, so little production moves abroad. In addition, either a common carbon price or one scaled to national income could raise approximately $186 billion a year for member countries.

This research helped inform the Open Coalition on Compliance Carbon Markets, launched at COP30 in Belém last year.

The findings suggest that coordinated action on a handful of heavily traded materials could deliver meaningful near-term climate gains without requiring every country to agree at once.