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Taxation, Representation, and Climate Migration

January 21, 2025


  • In areas losing residents due to climate change, an aging, poorer population will likely struggle to raise public revenue adequate to their needs and may face marginalization due to declining representation.
  • In places seeing climate-driven population instability, it will become harder to administer inclusive elections and fiscal pressures may encourage gentrifying redevelopment.
  • Regions seeing in-migration due to climate change will benefit from new economic and fiscal vitality if they successfully incorporate newcomers.
  • Without policy change, climate migration will likely worsen economic and racial inequality in America. A comprehensive policy research agenda is necessary to address the fiscal and democratic challenges of climate-driven migration.
Juan Jose Muñoz, left, and Elvin Antonio Urbina walk with their belongings through a flooded street in North Tampa, Florida, on Thursday, Oct. 10, 2024, a day after Hurricane Milton crossed Florida’s Gulf Coast.
Juan Jose Muñoz, left, and Elvin Antonio Urbina walk with their belongings through a flooded street in North Tampa, Florida, on Thursday, Oct. 10, 2024, a day after Hurricane Milton crossed Florida’s Gulf Coast. Pedro Portal/Miami Herald

Man-made climate change is already provoking mass migration. As environmental conditions worsen, that trend will accelerate. Within the United States, large regions that are currently heavily populated will become increasingly difficult to live in, and tens of millions of Americans will respond by moving.

After reviewing what we know about climate migration, we turn to the fiscal and electoral implications of that migration within the United States. Political inertia is the primary barrier to climate action—not a lack of scientific data, technological prowess, or national resources. So it is vital to understand how climate change, including climate migration, will alter our political system. At the core of the political system are representation and taxation: the process by which political decision-makers are chosen and the process by which political decisions are funded.

The paper is divided into three parts, examining the electoral and fiscal issues for places losing population due to climate change, places experiencing population instability, and places gaining population. In each of these scenarios, under current conditions, climate migration will likely exacerbate racial and class disparities of wealth and political power. The paper concludes by proposing a research and policy development agenda to better equip the policymakers that will be responding to climate migration.

Climate Migration: A Review

Predictions regarding climate migration are highly tentative, but the best estimates suggest that, globally, climate stressors will lead  over 100 million people to move, often within their own countries, over the next 75 years. As Abrahm Lustgarten has documented in his book “On the Move,” tens of millions of Americans will likely be among the displaced. In fact, the First Street Foundation, which models climate risk, has calculated that climate change-related flood risk has already reduced the U.S. population of the highest-risk areas by 3.2 million.

Climate stresses are being felt in all regions of the country, but some areas are particularly vulnerable. The Southwest is experiencing extreme heat and serious water shortages, and those problems will worsen. Millions of Americans living on the coasts have homes at risk of inundation by sea level rise. Climate change is reducing crop yields, encouraging out-migration from America’s farmlands. The expanding range, frequency, and severity of wildfires, floods, and hurricanes will drive even more Americans from their homes.

One challenge of modeling climate migration patterns is that current trends are not a clear predictor of future behavior. Recent decades have seen relatively low levels of interstate mobility and population booms in places at very high risk of climate disaster. Sun Belt cities are growing faster than cities in other regions. There is, however, some evidence that residential patterns are changing as people consider the risks of climate change in their housing choices, a trend that will accelerate as home insurance becomes increasingly unaffordable or unavailable in high-risk areas. When tipping points occur, neighborhood home values will likely experience cascade effects.

Broadly speaking, climate change is expected to push the U.S. population inland, northward, into cities, and uphill. This is not to suggest most people will abruptly move thousands of miles; most people who move, including those moving in the wake of disaster, go to neighboring communities or nearby states. Climate change will also redistribute populations within localities, particularly in areas where flooding is an increasing risk. Moreover, the movement of people will not be uniform. There will be both gradual movement in response to background conditions like increasing heat, and sudden evacuations in response to specific disasters, like hurricanes.

Studies of previous migrations provide some suggestions about who, faced by ecological disaster, is most likely to move. Among the most mobile are people with fewer ties to the local community: young people and renters. People with greater educational attainment also tend to move more. The elderly and homeowners are more likely to stay (or, in the case of sudden and extreme disasters, more likely to return and rebuild). There is also a partisan divide in exposure to climate risk; Republicans are more inclined to own properties threatened by sea level rise—an apparent consequence of longstanding denial of climate change within the Republican Party.

Wealth both makes it easier to move and easier to remain. Marginalized communities are more likely to live in places exposed to climate pollution and vulnerable to climate disasters but face added difficulties in moving away from or evacuating affected areas. They are also less likely to receive adequate assistance in the aftermath of disaster and are more likely to face difficulties in returning home after evacuation. Climate disasters have therefore exacerbated economic inequality.

Population Decline

As the effects of climate change intensify, some areas of the United States will see their population go into secular decline. Where the climate is becoming especially inhospitable, it is poorer and less urban areas that are most immediately vulnerable to population erosion. Metropolitan areas are more economically vibrant than rural areas, and wealth increases the capacity to fund climate-mitigating infrastructure. Rural areas are also especially dependent on reliable weather; agriculture is, of course, on the front line of climate change.

In some cases, depopulation is occurring in an organized fashion, through what is known as “managed retreat”: the coordinated movement of a community to a new location. Coastal Louisiana’s Isle de Jean Charles was in the process of eroding into the Gulf of Mexico when the community, with a grant from the Department of Housing and Urban Development, resettled on higher ground. In 2023, the Jean Charles Choctaw Nation, whose homeland was on Isle de Jean Charles, filed a complaint alleging that Louisiana’s Office of Community Development violated their civil rights by excluding tribal leaders from decision-making surrounding the retreat after funding had been allocated.

The case of Isle de Jean Charles indicates the vital need for community-directed decision-making in response to climate change—a need no less significant in places where population decline will occur less systematically, through gradual attrition, sudden evacuations, or a combination of the two.

Ensuring the civic rights and self-determination of communities seeing depopulation is especially challenging because those areas will see declining wealth and declining representation. Depopulating areas will experience reduced electoral representation, both within states and nationally, as districts are reapportioned. The political implications of these changes will undoubtedly be quite substantial. Florida has seen its delegation in the House of Representatives grow by about 90% from 15 members in 1980 to 28 today; Michigan, by contrast, lost more than a quarter of its House seats over the same period. It is plausible to imagine climate change reversing, or more than reversing, this shift in apportionment over the decades to come.

Apportionment of the U.S. Senate will not be altered by population shifts, of course. To the extent that climate out-migration occurs in rural states more than urban ones, it would increase the Senate’s rural bias. But it is not obvious whether climate migration will make the Senate more or less representative of the nation as a whole; states particularly exposed to climate stressors include many of the most-populous states (e.g. Florida, Texas, and California) and many of the smallest states (e.g. Delaware, Rhode Island, and Hawaii).

Localities with a declining population may also see substantial change in their partisan balance. These places will likely have a poorer remaining population, both because people with resources will leave and because the local economy will decline. How rising poverty will affect voting patterns is unclear. Democrats have an advantage among lower and lower-middle income voters, but American partisanship is also split along racial and educational lines; white voters without a college degree support the Republican Party about 2-to-1 over the Democratic Party, while three-fifths of Hispanic and over four-fifths of Black voters without college degrees are Democrats. Places experiencing population decline will also likely have an aging population, which usually skews more conservative.

Whatever their partisanship, depopulating areas will see very serious fiscal challenges. The tax base will decline due to falling property values and a shrinking working-age population. These localities will find it harder to borrow but will need additional infrastructure investments to offset the physical damage of disasters and additional services for an older and poorer population coping with an increasingly harsh physical environment. In short, these communities will have more needs but less money to address those needs.

Failure to support people in depopulating places presents a serious risk to political stability and democratic practices. Places experiencing emigration see a rise in support for radical right parties, in part because the remaining voters tend to be more conservative, but also because of reactions to the economic decline associated with population loss. Cuts to public services and housing foreclosure increase support for the far right. 

The political challenges facing depopulating areas are exacerbated by the U.S. tax system, under which local governments are responsible for many public investments and are heavily reliant on property taxes. Places with declining population will see declining home values, undermining the capacity of locales to provide for their remaining citizens. State and national intervention will be necessary to ensure the availability of public services in areas seeing climate out-migration. In addition, as the economy declines, those who remain will require greater protections for their personal welfare. Strengthening federal social insurance protections for the elderly poor is an important component of protecting the people living in depopulating places.

Population Instability

Many places will see population instability in the face of climate change. Most obviously, there will be places that see abrupt population declines in the immediate aftermath of disasters; in the months and years that follow, it will not be clear what fraction of the former population will return. We may also see a rise in seasonal residence patterns, in response to part-year dangers like extreme heat and seasonal storms. As we destabilize the climate system, some places thought to be climate refuges will themselves become disaster areas. Hurricanes, for example, are often perceived as a coastal risk, but 2024’s Hurricane Helene devastated a large swathe of inland North Carolina.

Cities in increasingly inhospitable climates are especially likely to experience instability, as they both bear the brunt of climate change and receive population from high-risk areas. One consequence can be climate gentrification. In Miami, for example, developers of expensive properties have increasingly sought to build in higher elevation areas, raising prices in historically lower-income neighborhoods.

Population instability will have substantial consequences for both taxation and representation. It is difficult to administer an inclusive, voter-friendly election when it is held during or soon after a major disaster—particularly because disasters are especially destabilizing for people from marginalized communities. When people move, they become less likely to vote, both because they must re-register and because they often lose social ties that encourage participation. The effect can linger for years. Disasters make it harder for voters to make it to the polls and differentially disenfranchise marginalized communities.

The short-term effects of disasters on turnout can be mitigated, recent research has shown. It is important to diversify election access by permitting early and absentee voting and publicizing these options ahead of time. Consolidating and changing voting places should be avoided as much as possible. Local elections administrators can create “Continuity of Operations Plans” when preparing for potential disruptions, which reduces pressures on election administrators to create plans after disasters happen. For example, a plan might describe how election officials would proceed in the event of flood damage to voting machines. FEMA also provides emergency management training, which can also help provide training and guidance to election officials in the event of a disaster.  

Over a longer time period, however, climate gentrification can fundamentally alter the politics of a city. In New Orleans, the composition of the voting public changed after Hurricane Katrina; though the city’s total population eventually rebounded, there were substantial declines in the share of population that is Black. In 2007, two years after the hurricane, the city had a majority-white City Council for the first time in decades.

Ensuring that communities can rebuild sustainably, without pricing marginalized communities out of their homes, is one of the most serious challenges of climate change in population-unstable locations. One piece of the solution is a reconsideration of the role of the property tax in local government funding systems. The local fiscal effects of disasters are mitigated, but not eliminated, by federal disaster aid, welfare spending, and private insurance payouts. Rebuilding spurs economic activity and temporarily increases sales tax revenue—and politicians reap a political reward for this recovery. But these investments do not resolve the fundamental inequities built into the American housing and property tax system—inequities that will be exacerbated by climate change.

Already, poorer communities struggle to raise revenue; their challenges will multiply as climate pressure grows. Major hurricanes reduce local revenues, resulting in a decline in public spending, deficits, and lower municipal bond ratings. After a hurricane, municipalities see interest rates on debt that are 1% higher. These revenue challenges will only grow more severe over time. Exposure to future sea level rise raises the costs of long-term municipal borrowing, and disasters have cumulative negative fiscal effects. These fiscal problems are even more serious in communities with large populations of poor or non-white people. 

The need for property tax revenue also encourages governments to greenlight unsafe development for wealthy residents. “The fiscalization of land use,” as urban planners Linda Shi and Andrew M. Varuzzo put it, “has driven and is driving cities to continue building on the waterfront, despite clear evidence that this is a bad idea in the long-term.” There is, they note, an “underlying tension between land-based local government finance and climate change adaptation.” There is equally a tension between our current property tax system and climate justice.

Population Increase

Places less exposed to climate disasters will see their population increase in the years to come. The political character of these communities will be altered, both by the dislocations associated with mass immigration and by the political character of the new arrivals.

Rapid in-migration can result in shortages of essential goods, especially housing, and higher demand for public services. It is plausible that some communities will see both increased need for social assistance, due to the arrival of poorer immigrants, and immigration-induced gentrification, as wealthier incomers price out longstanding residents. But a growing population, and the relocation of industry, can also bring revitalization. Despite political rhetoric to the contrary, most studies find that immigration does not have a long-term negative impact on aggregate wages or unemployment. Places receiving climate migrants in Texas and Florida have not seen rising unemployment rates.

Communities receiving large numbers of climate migrants will experience substantial political change. For one, a large population inflow can markedly change the political composition of a community. Domestic migrants often bring their politics with them to a new part of the country, though they also tend to pick places to live that are politically congruent with their views.

It will take time, however, for migrant Americans to find their political voice. Because of the dislocation and loss of social ties caused by migration, it can be challenging for even internal migrants to involve themselves in the local politics of their adoptive homes. There is some evidence that politicians are less inclined to represent the interests of internal migrants. An important consideration for communities with population instability is to build local institutions that encourage political and social incorporation. An easy first step is to reduce the red-tape barriers to voting by making registration automatic and portable.

This need for social and political incorporation is reinforced by the other political effect of in-migration: the response of longtime residents. People often react to immigration from abroad by supporting xenophobic parties and opposing economic redistribution. Individuals’ opposition to immigration is not well-explained by personal economic considerations, like the risk of losing one’s job to an immigrant. Instead, ethnic prejudice and fear of cultural change are at the heart of anti-immigrant sentiment; concerns about the economy play a secondary role.

Similar dynamics have been found in the response to domestic migration. In the United States, evidence from the Great Migration, Hurricane Katrina, public housing demolition, and even an experiment conducted at train stations suggests that white Americans tend to develop more exclusionary attitudes when people of a different race or ethnicity move near them. There is therefore a serious risk that communities receiving domestic migrants will react with hostility, especially when those newcomers are of a different race or ethnicity or if migrants are perceived as a drain on local resources.

There is a growing literature on how local communities can build the institutional capacity necessary to successfully incorporate migrants. International immigrant resettlement in Europe also provides some insight into how funding from state and central governments can help communities foster meaningful and positive contact between migrants and natives and reduce anti-migrant attitudes. Funding from the federal government could also incentivize a wider array of communities to welcome migrants, another strategy that effectively reduces the likelihood of backlash.

Political leaders will play a key role in either fomenting or mitigating anti-migrant sentiment. As political scientist Daniel Hopkins has noted, “hostile political reactions to neighboring immigrants are most likely when communities undergo sudden influxes of immigrants and when salient national rhetoric reinforces the threat.” But if political leaders can activate their constituents’ prejudices, they can also reduce hostility to immigrants through their rhetoric, their policy decisions, and their political coalition-building.

During the early and mid-20th century, six million Black Americans moved out of the South. Despite the backlash this migration engendered, the Great Migration increased support for civil rights among white Americans. In the northern and western cities, Black Americans became a crucial urban voting bloc and a critical portion of the industrial workforce. Eventually, they achieved an extraordinary political feat: turning the Democratic Party, the party of “Jim Crow” segregation, into the party of civil rights. As we think about climate migration, there is much to learn from the process of political realignment that occurred in the northern Democratic parties and in the union movement.

One immediate issue of migrant incorporation is the costs associated with immigrants’ arrival; unlike places directly hit by disasters, there is not yet a system in place to provide standardized federal support to receiving communities. Another critical issue is interstate portability; when essentials like health insurance are tied to a specific job, or licenses or benefits are administered at a state level, it creates immediate challenges for migrants’ incorporation. A third challenge is the longstanding housing shortage in the United States.

If communities receiving climate migrants can avoid the ill-feeling and scarcity mindset, immigration provides the opportunity for substantial fiscal gains. As long as communities have the resources and the will to incorporate newcomers, population increases should substantially strengthen local government budgets through new economic activity, growth, and therefore tax revenues.

Conclusion

In the coming years, migration within the United States will increase due to climate change. It is vitally important that we plan for the upheavals this migration will entail.

Some places will see declining population. In these areas, an aging, poorer population will likely struggle to raise revenue adequate to their needs and may face marginalization due to low and declining representation and wealth. Other places will see population instability. In these areas, it will become harder to administer inclusive elections. The costs of rebuilding will also create substantial fiscal pressures, which may drive localities to prioritize gentrifying redevelopment. Finally, some regions will see population growth. These areas will need to work to incorporate migrants but should be in the best fiscal shape of the three, as long as resources are available at the outset to welcome migrants. A critical question in all three population scenarios is how to prevent the impact of climate change from worsening inequities of race and class.

More research is needed to incorporate climate resilience and climate justice into our fiscal and electoral systems. This research should include:

  • Better and more granular public data collection on climate risk. Equitably planning for climate change requires more precise climate risk models that can account for social inequality at a local level.
  • Additional research to complement the growing literature on resilient election systems, including best practices for election administration in disaster scenarios and more intra- and inter-state coordination to increase the portability and reduce the administrative burden of voter registration.
  • The development and assessment of pilot programs to reduce the barriers to and costs of mobility for those in especially climate-exposed regions, including by increasing benefit access and portability, with a special focus on the needs of marginalized and poor people.
  • Further rigorous analysis of effective programs to incorporate migrants and the development of funding mechanisms to make these programs scalable.
  • New research on how to support places experiencing outmigration, including ensuring the maintenance of baseline public goods, and increasing protections for the elderly and especially the elderly poor.
  • Further research on reducing political extremism and anti-immigrant sentiment in places with declining population.
  • A fundamental reconsideration of the role of the property tax in local finance and of homeownership in individual wealth accrual. Many of the challenges facing communities in the context of climate migration stem from deep, longstanding inequities in housing and local public goods provision, a system in which the property tax is deeply implicated. More research is needed to explore how fiscal reform could help create inclusive and climate-resilient communities.

No public policy agenda will eliminate the wrenching decisions people will have to make about whether and when to leave their homes. And no mitigation or adaptation strategy is a replacement for ending the economic practices that are destabilizing the global climate. The most essential strategy to address climate migration is to eliminate its cause: to implement the policies necessary to stop global warming, most obviously by replacing fossil fuels with other energy sources. What is more, the policies necessary to decarbonize the economy also raise the public money required to develop new sustainable economic systems and to alleviate the suffering caused by climate change.

But because the climate is already changing, we must simultaneously address the causes and the consequences. New policy research is required to mitigate the electoral and fiscal dislocations that will accompany climate migration. If we are to keep the impacts of climate change from disproportionately harming marginalized communities, and if we are to ensure that those affected by climate change have a voice in climate policymaking, we must tackle the challenge climate change poses to the most fundamental components of our political system—taxation and representation.

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