Climate may force millions to move and U.S. isn't ready, report warns

Global warming may push millions of Americans away from the coast, and the U.S. isn’t prepared for the consequences of such a mass migration, scientists from across the federal government warned on Friday.

“Sea level rise might reshape the U.S. population distribution,” the scientists wrote in a sweeping report on climate change. “The potential need for millions of people and billions of dollars of coastal infrastructure to be relocated in the future creates challenging legal, financial, and equity issues that have not yet been addressed.”

Climate change continues to outpace efforts to adapt

The warning comes in the latest edition of the National Climate Assessment, a compendium of research about the state of climate change released every four years by scientists and other experts from across federal agencies. The assessment finds that climate change continues to outpace efforts to combat it or to adapt to its effects.

The report comes at a time of worsening natural disasters like hurricanes and fires in the U.S., which exceeded a record $300 billion in costs in 2017. Those incidents have highlighted the exposure of vulnerable communities; in October, Brock Long, administrator of the Federal Emergency Management Agency, excoriated coastal communities and states for not doing more to protect their residents from hurricanes.

The prospect and consequences of large-scale migration receive more attention this year than in past editions of the report. In 2014, for example, the section on the Northeast U.S. made no mention of people being forced to move. In the version released on Friday, migration was a large focus.

“Coastal states such as Massachusetts, New Jersey, and New York are anticipated to see large outflows of migrants, a pattern that would stress regional locations further inland,” the authors write. “City leaders hope to avoid forced migration of highly vulnerable populations and the loss of historical and cultural resources.”

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Yet those movements are all but certain to take place, not just in the Northeast but around the country. “In all but the very lowest sea level rise projections, retreat will become an unavoidable option in some areas of the U.S. coastline,” the authors wrote.

Social, legal & economic challenges of migration

The report’s section on coastal states is even more explicit about the social, legal and economic challenges posed by the movement of large numbers of people. “Communities face difficult questions about determining who will pay for current impacts and future adaptation and mitigation strategies and if, how, or when to relocate,” the report warns.

The decision about when and how to flee the effects of climate change depends on emotional factors as well.

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“Coastal communities have ties to their specific land and to each other, as is the case from the bayous of Louisiana, to the beaches of New Jersey, to the sea islands of South Carolina and Georgia,” according to the report. “These ties can impede people’s ability and willingness to move away from impacted areas.”

The federal government has haltingly begun preparing to move whole communities from the coast. In 2016, the Obama administration gave $48 million to Louisiana to move a small village inland. The administration also tried to establish an interagency working group to develop policies to support “managed retreat” from the coast. After Donald Trump became president, the group stopped meeting.

Coastal communities need to do more to prepare

While the timing and speed of climate migration is uncertain, the authors warn that this much is clear: The parts of the country most exposed to climate change haven’t put enough thought or money into preparing for it. They note that coastal communities have been slow to look at preventing development in risky areas, or retreating from those areas.

“The scale of adaptation implementation for some effects and locations seems incommensurate with the projected scale of climate threats,” the authors wrote in the report.

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