Shipping was excluded from the Paris climate agreement adopted under a United Nations framework in 2015, with governments entrusting the International Maritime Organization to come up with a consensus on carbon reduction measures from ocean going vessels.
IMO Secretary-General Kitack Lim has said shipping will do its part to contribute to the Paris accord, but the regulator has been criticized of moving slowly, leaving open the potential for regional regulators like the European Union to move first to enforce their own rules.
Shipping contributed about 3.1 percent of total annual carbon dioxide, or CO2, emissions in the period from 2007 to 2012, according to an IMO study. But vessel emissions are projected to increase by between 50 percent and 250 percent by 2050 as global trade grows and carriers add capacity if no action is taken.
The debate has deep political fault lines, with many mainly developing countries arguing that strict emission standards will hurt their economies.
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