The estimated CO2 emissions of the average immigrant (legal or illegal) in the United States are 18 percent less than those of the average native-born American. However, immigrants in the United States produce an estimated four times more CO2 in the United States as they would have in their countries of origin. U.S. immigrants produce an estimated 637 million metric tons of CO2 emissions annually - equal to Great Britain and Sweden combined.
The estimated 637 million tons of CO2 U.S. immigrants produce annually is 482 million tons more than they would have produced had they remained in their home countries. If the 482-million-ton increase in global CO2 emissions caused by immigration to the United States were a separate country, it would rank 10th in the world in emissions.
The impact of immigration to the United States on global emissions is equal to approximately 5 percent of the increase in annual world-wide CO2 emissions since 1980. Of the CO2 emissions caused by immigrants, 83 percent are estimated to come from legal immigrants and 17 percent from illegal immigrants. Legal immigrants have a much larger impact because they are more numerous than illegal immigrants and because they have higher incomes, and thus higher emissions.
The above figures do not include the impact of children born to immigrants in the United States. If they were included, the impact would be much higher. Assuming no change in U.S. immigration policy, 30 million new legal and illegal immigrants are expected to settle in the United States in the next 20 years. In recent years, increases in U.S. CO2 emissions have been driven entirely by population increases, as per capita emissions have stabilized.
Discussion: Some may be tempted to see this analysis as "blaming immigrants" for what are really America's failures. It is certainly reasonable to argue that Americans could do more to reduce per capita emissions. And it is certainly not our intention to imply that immigrants are particularly responsible for global warming. As we report in this study, the average immigrant produces somewhat less CO2 than the average native-born American. But to simply dismiss the large role that continuing high levels of immigration play in increasing U.S. (and thus worldwide) CO2 emissions is not only intellectually dishonest, it is also counterproductive. One must acknowledge a problem before a solution can be found.
One can still argue for high levels of immigration for any number of other reasons. However, one cannot make the argument for high immigration without at least understanding what it means for global efforts to reduce the emission of greenhouse gases. Some involved in the global-warming issue have recognized immigration's importance. For instance, chief U.S. Climate negotiator and special representative for the United States, Harlan Watson, has acknowledged that high immigration to the United States is thwarting efforts to reduce the nation's emissions. "It's simple arithmetic," said Watson. "If you look at mid-century, Europe will be at 1990 levels of population while ours will be nearing 60 percent above 1990 levels. So population does matter." This research confirms Watson's observation.
The Center for Immigration Studies is an independent research institute that examines the impact of immigration on the United States.
