China, the United States, India, Japan, and Russia are the top five countries emitting the most carbon dioxide. The top five emitters per capita are Qatar, Kuwait, Saudi Arabia, Canada, and the United States.
However, if you look at the top five countries that have produced the most CO2 from 1975 to 2020, you will find Germany and the U.K. on the list, behind the United States, China, and Russia.
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Source: Climate Watch