Cargo ships must cut their emissions in half by 2050

Nations most at risk from sea level rise had pushed for the U.N. to set a bigger reduction

cargo ship

BLACK SMOKER  A new international agreement places a cap on greenhouse gas emissions from international cargo ships.

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A new, hard-fought international deal will set limits on greenhouse gas emissions from international shipping for the first time.

Delegates to the United Nations’ International Maritime Organization, or IMO, met for a week in London to hash out the details of the plan. On April 13, more than 170 states agreed to the new road map, which aims to reduce shipping emissions at least 50 percent below 2008 levels by 2050.

Currently, international shipping emissions make up about 2 to 3 percent of global emissions of greenhouse gases, including carbon dioxide and methane. That’s roughly on par with Germany’s annual emissions. And a 2014 IMO report calculated that international shipping emissions were on track to increase 50 to 250 percent by 2050. These emissions were not included in the 2015 Paris climate agreement, the international pact to limit global warming to “well below” 2 degrees Celsius (SN: 1/9/16, p. 6).

Every year, tens of thousands of cargo ships crisscross the ocean, hauling everything from cars to coffee. Such ships largely rely on heavy fuel oil, which both contributes to greenhouse gas emissions and is a public health hazard, containing as much as 1,800 times the sulfur of diesel fuel, says James Corbett, an expert in global shipping at the University of Delaware in Newark.

The new agreement focuses on the carbon emissions. It lays out an initial strategy to reduce emissions by encouraging shipping companies to make their ship designs more energy efficient, use alternative fuels or energy sources and streamline operations so that they consume less energy.

The deal is an important milestone, Corbett says. “Clearly the IMO is moving into the 21st century,” he says. “The main issue that the IMO will continue to have to wrestle with is timing.” The organization, he adds, will need to walk a line between allowing the shipping industry time to adopt and prove new ship technologies — but not allow the industry to delay too long to meet environmental targets.

Shipping industry groups have hailed the new agreement as a landmark deal. Peter Hinchliffe of the International Chamber of Shipping in London called the deal “a Paris Agreement for shipping” in a statement released April 13.

Climate activists, who had hoped for more stringent regulations, had a more muted reaction. Veronica Frank, a Greenpeace International political adviser, told Reuters that the plan was “far from perfect, but the direction is now clear — a phaseout of carbon emissions.”

The plan also falls short of some nations’ hopes. Island nations threatened by sea level rise, such as the Marshall Islands in the western Pacific, have for years urged the IMO to push for a 100 percent emissions reduction by 2050 as the only strategy consistent with the goal of limiting global warming to 1.5 degrees Celsius relative to pre-industrial levels.

Other nations, including members of the European Union, had proposed at least 70 percent reduction in emissions by 2050. “What is on the table is the bare minimum, and it’s not good enough,” Netherlands delegate to the IMO meeting Bas Eickhout told reporters on April 10, after the draft plan was revealed. After the April 13 vote, the EU issued a statement calling the 50 percent reduction “a good starting point.”

Carolyn Gramling is the earth & climate writer. She has bachelor’s degrees in geology and European history and a Ph.D. in marine geochemistry from MIT and the Woods Hole Oceanographic Institution.

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