Would a global tax on shipping’s carbon output hurt developing economies?

Analysis by Clarksons Research and commissioned by a shipowners group has found that a levy that is much higher than $100 per tonne of CO2 would likely be viewed by some countries as having a disproportionally negative impact on some trades.

But the full range of carbon levy levels — up to $400 per tonne — that are under consideration at the International Maritime Organization would have a more modest impact on the cost of delivered cargo, a measure that is more relevant to the impact on the economies of member...