Climate Change Poses a Widening Threat to National Security

While the report focuses on climate migration overseas, it notes that some Americans are already moving because of the effects of climate change as well. “Even in the United States, one extreme event can result in a relatively high degree of permanent relocation of low-income populations exposed to chronic and worsening conditions over time,” the report says.

In February, Mr. Biden signed an executive order directing the National Security Council to provide options for protecting and resettling people displaced by climate change, as well as how to identify them.

In response, the report released Thursday, which was supposed to be done by August, recommends that the White House “work with Congress to create a new legal pathway for individualized humanitarian protection in the United States for individuals facing serious threats to their life because of climate change.”

The report also calls for setting up a group of staff across government agencies to coordinate American policy on climate migration.

Experts in climate migration said the report could have gone further.

Teevrat Garg, an economics professor at the University of California, San Diego, who specializes in climate migration, welcomed the administration’s attention to the issue. But he said the report could have addressed the deeper question of what the United States and other developed countries owe to climate migrants.

“Much of the carbon emissions driving climate change have come from rich nations but the consequences are being borne disproportionately by the poor,” Dr. Garg said. As a result, wealthy countries have “an obligation to support climate refugees.”

Others were more critical. Kayly Ober, the senior advocate and program manager for the Climate Displacement Program at Refugees International, called the report disappointing — more of a review of the challenges around climate migration than a set of prescriptions for how to address it.

“It’s a huge missed opportunity,” Ms. Ober said. “I think the Biden administration hasn’t quite figured out what they want to do.”