Still, the United States has the largest per capita emissions in the world: Each person in the United States has a carbon footprint of 17.6 tons (16 metric tons), compared to just 2 tons (1.8 metric tons) for people in India, the study found.till, the United States has the largest per capita emissions in the world: Each person in the United States has a carbon footprint of 17.6 tons (16 metric tons), compared to just 2 tons (1.8 metric tons) for people in India, the study found.