As is well known in science and policy circles, civilization-altering climate change, marked by rising sea levels, floods, droughts, wildfires, and other natural disasters, is no longer a matter of if but when. Mitigation—reducing greenhouse gas emissions —by itself will not be adequate to attenuate some level of warming of the planet and its concomitant effects. If current trends hold, it is unlikely we will succeed in staying below either the 1.5 degree Celsius temperature threshold or even 2.0 degrees. Therefore, we must now also undertake methods of adaptation to ensure human society will be able to survive and thrive on a changing planet. Managed retreat—relocating communities threatened by climate change to more livable regions—is an extreme adaptation strategy that is grudgingly under discussion in an increasing number of locales across the globe.

While climate change will affect virtually everyone, the largely poor and densely populated areas of Latin America, South Asia, and sub-Saharan Africa are right in the cross-hairs. From desertification in Syria to sea-level rise in Madagascar to the cyclone-ravaged shoreline of Bangladesh, many of the countries least prepared to weather the storm, in terms of wealth and resources, will be hardest hit. According to the World Bank, these regions, which constitute more than half of the developing world’s total population, could produce 143 million internal climate migrants by mid-century. The number of cross-border climate refugees could reach as high as 1.2 billion by 2050, according to the Institute for Economics and Peace. Many of these international climate migrants will find their way to the United States.

In fact, one could argue they already have, as thousands massed on the south side of the U.S.-Mexico border flee not only political circumstances in many Latin American countries but in many cases also economic dislocations that have climate change as an important driver. These global flows on all continents create innumerable humanitarian and legal considerations, but in this article we focus on the more overlooked question of domestic climate displacement within the United States, which has its own legal and policy dimensions. One needs to add that flows of climate immigrants at the southern border will need to be addressed in their own context under international and domestic U.S. law, but that is beyond the scope of this article.

While we have already seen the beginnings of climate-induced displacement in the United States, most of the movement so far has been at the individual or household level, which is exceedingly difficult to track. Inevitably, we will experience a mass tide of people relocating great distances as their own communities become unlivable. The handwriting is on the wall for all to see if we dare to look at the latest messages: Forty million residents of the Southwest depend on the dwindling Colorado River, whose rate of drying up has already exceeded projections. The roughly one third of the U.S. population who live near the shore will have to contend with swelling seas. And more and more people are moving into those areas vulnerable to wildfire.

Last year, per Census Bureau data, 3.4 million Americans were displaced by a natural disaster, and 16 percent of them did not return home. That number is alarming, but these resulted from short-term events, not chronic conditions. In subsequent decades, domestic climate displacement will become a greater challenge in terms of numbers and complexity. Perhaps 13 million people in the United States will be displaced by the end of the century, according to Matthew Hauer. In a 2017 article in Nature Climate Change, he predicted that internal climate migration will “reshape the U.S. population distribution, potentially stressing landlocked areas unprepared to accommodate this wave of coastal migrants.”

However, despite the relatively recent attention to managed retreat in the planning processes of the already severely impacted regions around the globe, few in the United States have engaged with the equally thorny question of relocating the internally displaced climate refugees. Where will all these people go, and how will they be integrated into the places where they end up? Answering this important question requires that we begin to seriously focus on the receiving communities—the back end of managed retreat.

There is no strategy, no accepted best practices, no legal framework, and little serious research to prepare receiving communities in the United States for a massive influx of climate refugees. How will legions of displaced resettle and rebuild their lives after being uprooted in the climate crisis? How will receiving communities absorb, not the current limited flow of individuals and households, but the potential relocation of entire communities and towns in the tens of thousands? What role will government (at all levels) play in managing this unprecedented wave of migration, and how does that mandate intersect with the role of private industry, civil society, and other affected stakeholders in receiving communities? What will be the legal, regulatory, and policy implications at each level of scale?

We urgently need to start asking these questions, formulating answers, and testing possible solutions, because sooner or later, domestic climate refugees will be knocking on the door of towns and cities woefully unprepared to accept them. Between flooding, drought, wildfires, hurricanes, and other life-altering events, climate change is no longer a problem of the future, it is here today, and people are moving as a result.

Much ink has been spilled about those forced to relocate, but few are talking about the receiving communities where they will end up. Some researchers and journalists are starting to venture into this terra incognita of the climate discourse. Jake Bittle’s The Great Displacement: Climate Change and the Next American Migration examines the plight of people fleeing the parched fields of Arizona and the flood-prone lowlands of the Carolinas, in one of the few works to explore not just who is migrating, and from where, but the question of where they will land and what will happen to them. A few one-off journalism pieces have profiled towns such as Duluth, Minnesota, and Buffalo as potential “climate havens.” While recent reports by the White House and the Government Accountability Office have considered climate migration as a federal issue, the focus is largely on international-level displacement without actually contributing much in the way of a plan for domestic climate refugees. And Robin Bronen’s excellent law review analysis of the ongoing relocation of an Indigenous community in Newtok, Alaska, makes a clear-eyed plea for a comprehensive governance framework to aid relocating communities. However, she too says little about the implications for receiving communities, and how they might also take part in this framework.

To be clear, these piecemeal studies fall short of a concerted research agenda involving policymakers, experts, and affected stakeholders, much less anything resembling a broad plan of action. Additionally, our understanding of what to do and how to prepare is stymied not only by a lack of research but a lack of precedent. Past episodes of internal displacement within the United States offer no real road map. In the 20th century, the Great Migration of American Blacks from the Jim Crow South to cities in the North, Midwest, and West, and the westward flight of farming communities escaping the Dust Bowl, provide little more than cautionary tales, and certainly no model for how we might prepare receiving communities for the arrival of large populations of climate refugees. These past migrations unfolded in an ad hoc, individualized fashion, rather than under the aegis of a coordinated program. The migrants faced further woe on arrival in their new homes: Black transplants adapting to northern cities encountered entrenched racism and poverty, while migrant farmers traded the dusty, dying Midwest fields for subsistence living in communities that for the most part did not want them.

More recently, the exodus of people from Gulf Coast states following Hurricane Katrina and from Puerto Rico after Hurricane Maria might offer some clues about a way forward, but the applicability of their lessons is limited. For one, except for some patchwork support from aid organizations and the federal government, the movement of people from affected regions was not coordinated; it was a spontaneous disaster response rather than a planned strategy. Furthermore, these disasters were still relatively small-scale and localized compared to the coming sweeping climatological impacts. The timeline remains uncertain, but it is already clear that receiving communities in the United States will have to contend with an incoming flow of people at a drastically larger scale.

The case of Newtok, Alaska, whose population numbers in the hundreds, is also an inadequate template. Battered by erosion and melting permafrost, the community collectively decided to relocate to higher ground nine miles away, in concert with tribal, state, and federal authorities and NGOs that supported the plan. But that 15-year process cannot be described as a success—only 70 people have actually moved and at great expense. And Newtok is just one small town whose residents have the benefit of patience, advance planning, willing relocation (rather than being forced), and the limited assistance of authorities. Furthermore, the receiving community is only nine miles away and was built to accommodate them.

Given the scale and complexity of the potential challenge, it would be a grave mistake to let isolated communities, individuals, and families figure it out on their own, as swaths of the United States become increasingly incompatible with human habitation. There must be structure—rules of the game—to ensure that this gargantuan, unprecedented challenge is addressed justly, safely, and effectively, in a way that considers the needs of the migrants as well as the towns and cities that take them in.

An effective structure requires a coordinated framework of multilevel governance to enable receiving communities to fulfill their role, wittingly or not, as climate havens rather than chaotic way stations for the displaced. Such a framework will engage federal, state, regional, and local municipal authorities, in concert with employers, civil society groups, and other stakeholders.

Public-private partnerships—PPPs—will be key to crafting and executing such a plan. These formal relationships can harness the regulatory authority, mandate, and public funding of governments; the innovation, entrepreneurship, and resources of private industry; and the engagement of on-the-ground stakeholders in receiving communities to build durable, equitable, effective solutions.

One vision for the path forward suggests that a new Silicon Valley can take root in underserved areas whose preferable geography and ample natural resources are supplemented with the provisions of PPPs that can deliver the labor force, infrastructure, innovation, and capital—all rooted in an ethos of sustainability and social justice. These pilot programs could be replicated at scale if successful in the near term. We at Adaptation Leader and other neutral boundary organizations can coordinate experiments at various levels of scale, and across regions, as climate brokers on both the front end of managed retreat and the back end of receiving communities.

Federalism at least gives us a governing architecture to work with, separating powers among federal, state, and local entities. Ascertaining exactly who will be responsible, and for what, will be one of the foremost challenges. Adaptation is local by nature, but we also need the national reach, broad mandate, and vast federal government resources to unite disparate actors under one plan. Any successful approach must include both top-down and bottom-up components, ensuring that all affected, including migrants and the receiving communities, have a seat at the table.

We will also need to consider legal and constitutional questions. International treaties, namely the 1951 United Nations Convention Relating to the Status of Refugees, and its 1967 Protocol Relating to the Status of Refugees, enumerate the rights of refugees globally and defines responsibilities of host countries to civilians fleeing war and persecution. But those escaping climate disasters across borders do not meet the current criteria of refugee status, and the treaties do not govern internally displaced persons. Binding international agreements to address these gaps will help provide the vital legal architecture.

Thus far, we have mostly been talking about voluntary relocation. Is there the possibility that the state may compel Americans to travel to one place or another or forbid them from doing so, impinging on the freedom of movement? Who will move and who will stay? What about voluntary non-migration—already a real issue for some—that is largely livelihood-based? Is government-mandated relocation in the cards?

It is hard to fathom a forced-migration scenario, but it is also hard to fathom the inevitability of a world where millions of fellow citizens can no longer live safely in coastal cities devastated by flooding and hurricanes, or previously secure locales ravaged by drought, fire, and air temperatures the human body cannot withstand. The specter of limiting a constitutional right is likely to be met with serious opposition. Nonetheless, as we consider worst-case scenarios, there may be situations where such limitations on mobility may be warranted—such as when governmental authority can no longer provide for health and safety, when environmental conditions have degraded to the point of danger to human health, or when fragile and critical ecosystems become threatened and must be protected from further use.

The government might also find cause to exercise its power of eminent domain under the Fifth Amendment’s Takings Clause, which forbids “private property be[ing] taken for public use, without just compensation.” Though fraught with ethical considerations, this power has been used to enable large infrastructure projects in the past, notably, for example, the federal interstate highway system, a massive undertaking. Courts have interpreted “public use” flexibly, which means that the state could require mandatory buyouts of climate-endangered residences (a voluntary buyout program has already existed for some time), or invoke eminent domain to seize land in order to construct new residences or entire communities to resettle climate migrants. Potentially, a federally mandated climate displacement and relocation strategy might rely heavily on the use of federally owned lands as designated climate havens for certain populations. While such a strategy might avoid the takings question, it is sure to raise a panoply of other issues of first impression.

Once a governance and policy framework is in place, we can address the specific practical concerns receiving communities will face as they absorb climate diasporas. Practical considerations abound. Are there sufficient natural resources (water, land) to handle a population boom? Can the existing civil infrastructure, housing stock, and public schools accommodate a large population influx or will they buckle under the strain?

There is the prospect of impacts on the local economy. Housing prices may spike as arrivals scramble to find a place to live. Migrants are likely to settle in both urban and rural communities, which present respective challenges and advantages. For example, a report by Raleigh Tacy, Shameika Hanson, and Jessica Poulin, researchers at Antioch University New England, examined the probable effects of the climate diaspora in Vermont, which offers possible havens both urban and country. Rural development, especially when rapid and unregulated, can jeopardize the sensitive local ecology. Additionally, a lack of “zoning to prevent sprawl and promote compact development can lead to land fragmentation, erosion, diminished water quality, and infrastructure overload,” the researchers report.

Another concern is that mass migration is likely to amplify existing fractures in American society as perceived outsiders come into contact with established residents. If the racial, socioeconomic, or demographic makeup of the arrivals is distinct from that of the host community, tension may arise—a pattern described by cultural stress theory—a burden that not only international migrants commonly struggle with as they adapt to a new country. Such challenges have existed before climate change became a driver. Indeed, the term receiving communities was developed pre-climate change, referring to in-migration resulting from all drivers and motivations. Domestic climate migrants may encounter similar tensions as disparate groups unaccustomed to living alongside each other come into close (and perhaps abrupt) contact. Alternatively, harmful, long-standing patterns of racial and ethnic segregation in the places they left behind might recrystallize in their new communities.

Class conflict can also transpire as well-to-do locals may resent, or resist, the settlement of comparatively poorer residents. The opposite scenario is possible as well: a wave of well-heeled climate refugees landing in an economically disadvantaged area can raise the cost of living and spur interclass antagonism, as has been reported recently when, during the Covid-19 pandemic, affluent transplants from urban coastal cities bought up property in less wealthy rural communities in the mountain states.

Concerns about such climate gentrification have been widely reported, including examples in New Orleans, Miami, and the Hudson Valley. Clearly, receiving communities will need to employ an equity lens in their planning processes. As framed by the Georgetown Climate Center’s Managed Retreat Toolkit, this calls for decisionmaking and investments “reflecting—and not displacing—the needs, priorities, and historic and cultural character of current residents and neighborhoods.”

At the same time, we should temper our concerns about the problems receiving communities will face with an optimistic view of how future population flows may present opportunities for growth and revitalizing change, and for remaking marginal towns and moribund cities based on principles of sustainability and social justice.

One plus is that domestic climate refugees (who, for the most part, will speak the same language and share the same general cultural background) may be more easily resettled than foreign-born refugees, despite the vexing class and racial cleavages that exist in American society. But population movements can boost the economies of towns and cities that will benefit from the enlarged labor pool, entrepreneurial initiative, and new ideas that out-of-towners bring. Communities need people to thrive—the arrival of too many people can be overwhelming, but the right amount of inflow can be beneficial.

Sociologist Matthew Hoffman, writing in VT Digger, comments on the Remote Worker Grant Program that offers cash incentives for out-of-state workers to move to Vermont. Noting that population growth can be economically revitalizing, while acknowledging that the state’s land is being developed at an unsustainable rate, Hoffman raises the point that growth must be planned and coordinated, in accord with a principle of compact development, to offset the effects of overdevelopment and destruction of Vermont’s beloved natural landscapes. The same lessons can be applied to climate receiving communities: welcome and perhaps financially subsidize the arrivals not as an act of charity but as a boon to towns and cities, while keeping a lid on wanton development. Social harmony is, like ecology, a delicate balancing act between competing interests, but under the right conditions, can be symbiotic.

The key is to actively manage a new population influx rather than letting the chips fall where they may—another reason to develop a plan now, when time is still on our side. The climate diaspora will be characterized not only by a flow of people but of capital and ideas—ingredients that can power growth. These new inputs can provide the impetus for germinating a thriving new social ecosystem in climate havens—if we do it right.

Recognizing this fact, some forward-looking cities and regions have already started to tenuously explore a future role as a climate haven. Duluth has been touted (in the press and by the mayor) as one such place. Buffalo’s mayor has dubbed New York’s second-largest city as a “climate refuge city.” Many communities, especially in the deindustrialized Northeast and Upper Midwest, that should be relatively insulated from the worst effects of climate change might experience a reversal of their long period of Rust Belt decline by welcoming citizens fleeing inundated coastlines and rapidly warming southern and western states. Slowly, this reality is moving from the cloistered discussions of think tanks and government committees and entering the public consciousness. Letters in local papers are a bellwether for the coming change, as in a December 2022 letter by journalist John Hiner, a lifelong Michigan resident, who writes optimistically of his state’s future role as a climate haven while expressing misgivings about its infrastructure and housing capacity, a problem (or opportunity, depending on how one looks at it) that requires “preparation on a grand scale.”

Preparation is the watchword, and federal, state, and local governments should enact specific policies, and provide necessary resources, to support receiving communities. First, preparatory work is essential—perhaps funded federally but coordinated and implemented locally, to develop cultural competency, assess communities’ capacity for receiving migrants, develop a system of recordkeeping and information sharing (among agencies, groups, and state actors), and bolster social programs that will assist migrants in finding housing, employment, and other social needs.

Welcome centers in receiving communities can provide an identifiable physical location where resources and programs are consolidated under literally one roof, and may also serve as a way station for climate refugees seeking to be settled. For example, Florida officials opened a welcome center at Orlando International Airport where Puerto Rican citizens fleeing Hurricane Maria could be informed about housing, health care, and disaster assistance. A similar program was set up in Houston for Louisiana residents displaced by Hurricane Katrina. However, these centers were created with a short-term outlook as a form of emergency support, rather than a sustainable, long-term response to the much broader and more drawn-out problem that will confront us. Hastily erecting support hubs in the aftermath of one-off disasters will not be adequate for climate change receiving communities. We must lay the groundwork now.

Moreover, we will need to expand federal assistance to states, municipalities, and individuals. Current federal grant programs related to disaster relief are not suited to the projected needs of receiving communities. HUD’s Community Development Block Grant–Disaster Recovery, for example, is tailored to recovery, rather than the secondary impact of migration. However, as Rachel Bogardus Drew and Ayate Temsamani note in a 2023 policy brief on “Preparing Receiving Communities for Climate Migration,” there is some leeway in how these funds can be applied, so shifting from a more reactive, disaster recovery approach to a proactive outlook is prudent; namely, by “hiring staff to develop and manage migrant-specific systems, expanding existing public assistance programs to meet higher demand, and supporting community institutions directly engaged with the migrant population. It could also be used to expand housing options and affordability in receiving communities with tight private markets through the building of more resilient housing that can withstand future harm, thereby stopping the risk cycle for receiving communities facing their own climate impacts.”

Meanwhile, governments should work hard to bolster public transit options, ideally by actually building transit infrastructure (expanding bus lines and routes and constructing mass transit systems), but if that is not feasible, then by subsidizing transit passes for climate refugees. Providing new arrivals a means of conveyance is essential to effective integration with receiving communities. Encouraging mass transit use will also be environmentally preferable and mitigate traffic problems that result from an influx of new motorists.

That last measure highlights an important point within the discussion: preparing receiving communities for the road ahead will work best when guided by an ethos of sustainability—which we define as an integration of environmental protection, responsible economic development, and social justice. Adaptation is not merely a question of moving people from one abode to another, but about changing how we live to ensure our continued survival as a species. After all, we cannot supersede the climate crisis by simply relocating the same ecologically and socially destructive habits that created the problem in the first place.

Launching small-scale pilot projects will be key to assessing which places and approaches are suitable for the job. We should look to prior experiments with “intentional communities,” such as transition towns and eco-villages — particularly those with an ecological outlook or focus on sustainability — for ideas and models we might adopt at a larger scale.

Pilot programs will also depend on pioneering Americans willing to undertake these experiments in the near term, when relocation may not be imminently necessary—and they are, indeed, experiments, many of which may fail. We must innovate, iterate, and undertake a process of trial and error to see what works and use the resulting knowledge to build a framework at scale. And that depends on structures and institutions, such as government and industry, as well as individual actors—the residents themselves—working in concert.

Some first movers (a phrase taken literally here) will be ideologically or philosophically inspired by the prospect of collectively building a new way of life and forming part of the vanguard of a solution to a global problem with existential stakes—just as idealistic, restless, community-minded Americans in the past have picked up their stakes and reconstituted intentional communities based on shared ideals.

If ideological motivation is not sufficient, financial or material incentives may encourage involvement. These could include grants, low-interest loans, or housing vouchers that encourage residents of high-risk zones to put down roots in designated climate havens, not unlike the program of land grants that inspired Americans in the 19th century to venture across the frontier. The federal Department of Housing and Urban Development’s “opportunity zone” initiative, where underserved areas benefit from special tax advantages to spur investment, is another potential model.

The impact of climate displacement may be understood not merely as a “cost” (as staggering as that cost will be) but as an opportunity for economic renaissance in parts of the country in need of fresh blood and new life. Looking further ahead, we might encourage city-to-city programs (the pairing of “sister cities” that facilitate the relocation of residents from one to the other), state-to-state compacts, or region-to-region pipelines.

For example, a city in South Florida threatened by sea-level rise could partner with a destination city in Nebraska or Michigan, forging a path along which people and businesses may be relocated. If private-sector partners were involved in the overall relocation plan then it might be possible to package populations with a dedicated business opportunity for that potential workforce. One of the great misfortunes of displacement is the destruction of long-standing social ties and business ecosystems. To the extent these networks can be reconstituted in receiving communities, it will make adapting to the climate crisis much more palatable.

The coming tide of climate migration within North America will unleash an unprecedented period of social upheaval that will require experimentation, trial and error, and clarity of purpose. To avoid crisis conditions in localities across the country, we need a national strategy where decisionmakers at each level of scale have defined roles. Any such effort will have to be forward-thinking, so that those households that must relocate can do so preemptively and as part of an organized, well-supported, private-public project, rather than waiting until the floodwaters are at one’s door. An organized relocation, supported by a multi-governance approach, is infinitely preferable to a madcap scramble on a mass scale.

Getting there requires a research agenda and pilot projects that test assumptions and approaches and encourage, not hinder, new cross-jurisdictional arrangements. Ongoing interdisciplinary dialogue has already brought together a core group of policymakers and professionals—individuals who have already recognized that a solution depends on transcending our traditional ways of thinking and our respective professional silos. This core group is a laboratory for innovation focused on possible solutions to a civilizational crisis. But there are many more experts—government officials, urban planners, scientists, sustainability-minded businesspeople, etc.—who have been mitigation-oriented when it comes to climate action; now they must also engage in the adaptation discourse to contribute their valuable perspectives.

A cookie-cutter solution will not be adequate to address the varying needs and conditions of different receiving communities. The climate adaptation field will need to help structure the rules of the game for receiving communities, including processes and procedures that are realistic and equitable. We also need to develop the metrics and tools to anticipate and manage the many economic, social, and environmental challenges and opportunities.

With adequate preparation and investment, when the climate creates an acute shock or chronic stress in an area, receiving communities can be prepared to welcome the displaced, and not be concerned that their way of life will collapse as large numbers of transplants rush in—that in fact they will be enriched. No one is promising it will be easy or quick. But it must be done, starting now. TEF