Where Will People Go?

Natural disasters and environmental stressors such as rising average temperatures are forcing growing numbers of people in the United States and Europe to relocate. According to the Internal Displacement Monitoring Center (IDMC), the United States accounted for more than 11 million disaster displacements after major hurricanes prompted mass evacuations in 2024, placing the country first globally. Reflecting these trends, a survey from 2021 found that nearly half of Americans planning to move were already taking climate-related risks into account.

While these new mobility patterns have received considerable public attention in the United States, in Europe they have not been as thoroughly discussed. Yet, European countries are seeing similar shifts in mobility. Southern European countries such as Greece and Spain face record-high temperatures and increasingly severe wildfires, while northern countries, including Germany and Poland, are experiencing heavier rainfall and flash floods that are forcing people to leave their homes temporarily or permanently.

Most research and programs designed to address climate-driven migration have focused on the “Global South”, where the overall scale of displacement has been greatest. However, this phenomenon is also becoming increasingly visible in North America and Europe. Given their similar socioeconomic dynamics, policy environments, and environmental risks, cooperation between the United States and Europe can strengthen preparedness, support the modeling of diverse migration scenarios, expand the range of policy responses, and facilitate the transfer of solutions tested in one region but not yet applied in the other.

Cities will be at the center of this transatlantic exchange. Most people moving for weather or environment-related reasons remain within national borders, and roughly 70% settle in cities, accelerating urbanization. Many cities are already grappling with the consequences but lack the resources, capacity, or data needed to assess and plan for the long-term impacts on their communities, including on affordable housing, land use, public and social services, and employment. This lack of preparedness falls hardest on low-income and vulnerable populations. Without adequate protections, these residents will struggle to cope with the health, economic, and social impacts of rapid- and slow-onset weather events. Unmanaged scenarios exacerbate existing inequities through damage to less resilient low-income and social housing, the high costs of reconstruction or relocation, rising insurance premiums in at-risk areas, and increasing property values and “climate gentrification” in places perceived as safe and attractive.

Housing stability and affordability are especially threatened. A 2021 study found that 35 million US homes—nearly one-third of the national housing stock—are at high risk from natural disasters. Public and assisted housing, primarily serving low-income households and people of color, are especially vulnerable due to location, aging infrastructure, and decades of underinvestment. For example, in the United States, the number of affordable housing units at risk from coastal flooding and sea-level rise is expected to more than triple by 2050, reaching nearly 25,000 units. These inequities are compounded when, as is often the case, vulnerable groups resettle in higher-risk areas, increasing the likelihood of repeated displacement.

National support for and cooperation between local and regional governments is critical to effectively monitoring and managing the impacts of climate-driven migration on cities.

However, cities are affected in different ways, and these nuances must be better understood. A 2022 report from the National League of Cities identifies cities experiencing one of three types of impact:

• Vulnerable cities face climate risks and are losing population and tax revenue while struggling to recover and make infrastructure and housing more resilient.
• Recipient cities host short- and long-term migrants from their region while managing their own environmental and socioeconomic stressors.
• Destination cities position themselves as “climate havens” in low-risk areas with high vacancy, welcoming newcomers and pursuing growth.

Most research has focused on the vulnerable cities that are migrants’ starting places. However, as population movement increases, a fuller understanding is needed of how recipient and destination cities are affected. How can these cities prepare for incoming migrants, and how might they harness the economic and social opportunities that new populations can bring in sustainable and equitable ways?

This broader perspective underscores the range of urban, housing, and socioeconomic policies cities must take into account to address the issue proactively. While most local authorities in the United States and Europe do not yet explicitly address climate-related displacement, many already have capacity in areas relevant to effective responses, such as climate adaptation, resilient infrastructure, social inclusion, and integration. The task now is to transfer this knowledge.

As climate-related migration is primarily intraregional, coordinated action among neighboring cities will be key, particularly around data collection and assisted relocation. At the same time, international exchange and peer learning can strengthen local responses. Cities in the United States and Europe, in particular, stand to benefit significantly from sharing experiences and approaches. For example, US cities have more extensive experience with disaster-driven relocation and managed retreat programs, as well as environmental justice frameworks and policies to manage displacement more equitably. Cities such as Duluth, Minnesota and Cleveland, Ohio, as well as regions such as Central Appalachia, are among the first to create dedicated economic and strategic plans to position themselves as “climate havens” ready to welcome new residents and businesses. Further, US city networks such as ICLEI USA have begun to raise awareness about climate migration and support local governments that want to proactively prepare for incoming “climate migrants”.

European cities, in turn, often have more ambitious climate and environmental plans. Their urban, housing, and social policies tend to be more climate-informed, with stronger social safety nets and renter protections for vulnerable groups. Many European coastal cities—particularly in the Netherlands—possess long-term expertise in sea-level rise adaptation and water management, areas where many US coastal cities face significant challenges.

Learning from the strategies and policies of cities facing similar challenges across the Atlantic strengthens understanding of these emerging displacement patterns and their effects on housing, infrastructure, and access to essential services. Pragmatic in outlook and focused on addressing the everyday concerns of their residents, US and European cities are in a strong position to continue—and deepen—transatlantic cooperation around the shared challenges of the 21st century.

The views expressed herein are those solely of the author. GMF as an institution does not take positions.