CO₂ Emissions Embodied in International Migration from 1995 to 2015

Abstract

While present international CO₂ mitigation agreements account for the impact of population composition and structure on emissions, the impact of international migration is overlooked. This study quantifies the CO₂ footprint of international immigrants and reveals their non-negligible impacts on global CO₂ emissions. Results show that the CO₂ footprint of international immigrants has increased from 1.8 gigatonnes (Gt) in 1995 to 2.9 Gt in 2015. In 2015, the U.S. had the largest total and per capita CO₂ emissions caused by international immigrants. Oceania and the Middle East are highlighted for their large portions of immigrant-caused CO₂ emissions in total CO₂ emissions (around 20%). Changes in the population and structure of global migration have kept increasing global CO₂ emissions during 1995-2015, while the reduction of CO₂ emission intensity helped offset global CO₂ emissions. The global CO₂ mitigation targets must consider the effects of global migration. Moreover, demand-side measures need to focus on major immigrant influx nations.