Fossil fuel combustion is the dominant source of global sulfur dioxide (SO₂) emissions. With rapid globalization, the expansion of international fuel trade may have profound impacts on SO₂ emissions due to the mixing and the spatial reallocation of fuels with varied quality (e.g., sulfur contents), which has not been clearly addressed. Here, by introducing international fuel trade and three additional counterfactual scenarios, we first assessed the impacts of fuel trade on global SO₂ emissions for the period 1980–2030. It was estimated that in 2014 international fuel trade caused an increase in global SO₂ emissions from hard coal and oil consumption by 4% and 71%, respectively, with stronger influences found for individual countries. By changing the fuel trade choice, global SO₂ emissions attributable to fuel trade would be reduced by 78%. We also showed that such effects of fuel trade on SO₂ emissions continuously increased from 1980 to 2014 and will keep increasing in the foreseeable future due to more frequent fuel trading under globalization.

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国际燃料贸易对全球二氧化硫排放量的影响

化石燃料燃烧是全球二氧化硫（SO ₂）排放的主要来源。随着全球化的迅速发展，由于质量（例如硫含量）不同的燃料的混合和空间重新分配，国际燃料贸易的扩大可能会对SO ₂排放产生深远影响，这一点尚未得到明确解决。在这里，通过介绍国际燃料贸易和另外三个反事实情景，我们首先评估了1980-2030年间燃料贸易对全球SO ₂排放的影响。据估计，2014年国际燃料贸易导致全球SO ₂的增加。硬煤和石油消耗的排放分别增加了4％和71％，对各个国家的影响更大。通过改变燃料贸易的选择，可归因于燃料贸易的全球SO ₂排放量将减少78％。我们还表明，从1980年到2014年，燃料贸易对SO ₂排放的这种影响持续增加，并且在可预见的将来，由于全球化下燃料贸易的日益频繁，这种影响将继续增加。