Pentagon emits more greenhouse gases than Portugal or Sweden, study says

WASHINGTON (FOX 5 DC) - The United States' quest for national security isn't making the world any safer, new research says.

Military operations overseen by the Pentagon emitted about 59 million metric tons of carbon dioxide and other greenhouse gases in 2017, according to a new study by Brown University's Watson Institute of International and Public Affairs.

If the Pentagon alone were a country, it'd be the 55-worst polluting nation in the world, the study says. That's worse than countries including Portugal, Sweden and Denmark.

The study's lead author says the Department of Defense has taken steps to reduce its carbon emissions, such as making its vehicles more efficient and moving to cleaner sources of energy at bases.

But the Pentagon could reduce emissions further by cutting fuel-heavy missions to the Persian Gulf, considering renewable energy development has made access to oil less of a priority, she says.

The Pentagon called climate change "a national security issue" in a January report to Congress.

China is the world's largest emitter of carbon dioxide, followed by the United States.