From Africa to Southeast Asia, from the Caribbean to Bangladesh, millions are already being uprooted by climate change, an accelerating force behind increasingly devastating environmental catastrophes. Some are fleeing rising sea levels, while others desperately escape droughts that transform fertile lands into barren wastelands. By mid-century, this figure could rise to billions, making climate migration one of the defining humanitarian crises of our time.
As we stand on the threshold of a warming planet, the individual stories of those most vulnerable are often lost behind statistics. This crisis exacerbates existing inequalities, with communities in the global south -- those least responsible for the climate crisis -- bearing a disproportionate burden.
Thus, rises an urgent question: How can we transition from reactive crisis management to proactive and equitable solutions for climate migration?
What drives climate migration
While migration is a complex tapestry woven from various threads, the unraveling climate has become a stark and undeniable driver. Climate change, with its intensifying effect -- droughts, floods, and rising seas, profoundly disrupts the very foundations of livelihoods, stripping vulnerable communities of their ability to thrive in place.
For those with limited resources and adaptive capacity -- the "trapped populations" -- climate change becomes a force of displacement, not a choice. The decision to migrate is no longer a matter of aspiration but of survival, shaped by the cruel intersection of climate shocks and pre-existing inequalities in access to credit, education, social networks, legal protections, and Income.
A farmer in Bangladesh, a mother in Chad, or a family in the Pacific -- each experiences this crisis differently, shaped by poverty, governance failures, and environmental degradation.
On a global scale
The scale of climate displacement is staggering. In 2023, disaster displacement reached its third-highest level in a decade, with 46.9 million new internal displacements recorded globally (IDMC, 2024). Weather-related hazards like floods and storms were the primary triggers, displacing 9.8 million and 9.5 million people, respectively.
As of December 31, 2023, at least 7.7 million people in 82 countries and territories were living in internal displacement as a result of disasters that happened not only in 2023, but also in 2022. Bangladesh is one of the top five countries with 1.8 million of new internal displacements due to disasters in 2023 (ibid.).
Projections for the future are even more alarming. The World Bank’s Groundswell report predicts that by 2050 without urgent action, climate change could displace 216 million people within their countries across six regions: Sub-Saharan Africa, South Asia, Latin America, East Asia and the Pacific, North Africa, and Eastern Europe.
Similarly, the IPCC warns that over one billion people globally will face coastal-specific climate hazards by mid-century, with tens to hundreds of millions forced to migrate in coming decades (IOM, 2022; IPCC, 2022).
And these numbers are not just abstract estimates -- they represent the lives, cultures, and histories of people uprooted and forced to abandon their homes. While the emotional toll of climate-induced migration is clear, the economic impacts are equally devastating. The World Bank estimates that by 2050, climate migration could cost the global economy $7 trillion.
Furthermore, climate migration will reshape global demographics and geopolitical landscapes. As people move from vulnerable regions to safer areas, it will create pressures on infrastructure, housing, and social cohesion. In some cases, it may lead to tensions between native populations and incoming migrants, as is already being witnessed in parts of Africa and Europe.
By mid-century, this figure could rise to billions, making climate migration one of the defining humanitarian crises of our time
Bangladesh: A case study
Bangladesh, home to over 170 million people and one of the most densely populated countries on the planet, exemplifies this injustice.
Its position in the low-lying Ganges-Brahmaputra-Meghna delta makes it exceptionally susceptible to a confluence of climate-induced disasters: Rising sea levels, intensified flooding (exacerbated by glacial melt in the Himalayas impacting the river system), salinity intrusion, riverbank erosion, and increasingly frequent and severe cyclones.
The World Risk Report 2023 ranks Bangladesh ninth worldwide in terms of climate disaster risk. The World Bank also projects that by 2050, one in every seven Bangladeshis will be displaced by climate change related disasters.
This vulnerability is compounded by the fact that nearly 80% of Bangladesh’s land is classified as floodplain, with 28% of the population residing along the vulnerable coast. Rising sea levels alone are projected to inundate 17% of the country by 2050, potentially displacing 20 million people and resulting in the loss of 30% of its agricultural land. This loss poses a devastating threat to the over 87% of rural households who rely on agriculture for their livelihoods.
Climate change impacts, including increased flood frequency and intensity, more prolonged droughts, and erratic rainfall patterns, are projected to reduce Bangladesh's total rice production by 7.4% annually until 2050. This degradation of agricultural land directly intensifies livelihood insecurity in rural areas, yet the government currently lacks clear operational policies to support farmers in adapting to these escalating pressures and mitigating these looming insecurities.
As these climate stressors erode rural livelihoods and agricultural stability, migration to urban centers becomes a desperate survival strategy. Four major cities -- Dhaka, Chitttaging, Khulna, and Rajshahi -- have absorbed the majority of these internal migrants, leading to increased infrastructural strain, resource scarcity, overcrowding, and heightened social tensions.
This rapid urbanization is evident in the dramatic increase in population density. World Bank data from 2022 indicates a national average of 1,301 people per square kilometer, compared to 992 in 2000, with Dhaka's density exceeding 20,000 people per square kilometer in that same year.
Within this context, climate-induced migration transcends a purely environmental concern; it represents a profound socioeconomic and policy challenge. Overpopulation in cities, coupled with limited employment opportunities and often exploitative working conditions, forces many climate migrants into precarious low-skilled jobs.
These urban climate migrants face "double insecurity," struggling to secure both employment and affordable housing. This scarcity of decent work further reduces human security, potentially exacerbating tensions between local and migrant populations and increasing urban crime rates.
Mitigation through action
While governments focus on reducing emissions and building climate-resilient infrastructure, they must also plan for the inevitable: Relocating populations from high-risk areas. It is definitely more manageable, cheaper, and has a much higher scope of success -- if it can be done in advance than 10 years later. If we can plan it ahead, it will save the government's money, and it will also be kinder to the people who will have to bear the brunt of the climate crisis.
One of the proposed solutions to the climate migration crisis is managed retreat -- the planned relocation of communities away from vulnerable areas. While this idea holds promise, it is fraught with challenges. For example, the Isle de Jean Charles relocation in Louisiana cost $50 million for just 37 families. However, for developing nations like Bangladesh, the cost of such initiatives is prohibitive without substantial international support.
When it comes to managing retreat, cost isn't the only obstacle to planning mass migrations. Making long-term plans to move entire communities doesn't have much appeal at the ballot box of politicians. All countries rich and poor tend to be more interested in short-term band-aid solutions rather than long-term solutions to this particular issue.
International law and ethical principles establish that the historical polluters have a responsibility to assist climate-vulnerable communities. Climate justice demands that the global north acknowledge its historical contribution for greenhouse gas emissions and provide substantial support to global south countries like Bangladesh with climate finance, capacity-building, and technical expertise for adaptation and displacement management.
Global policy discussions must prioritize these areas, along with the development of effective international migration policy frameworks.
For those with limited resources and adaptive capacity -- the 'trapped populations' -- climate change becomes a force of displacement, not a choice
From reactive to proactive
A just and effective response to climate-induced urban migration in Bangladesh demands a rights-based, climate-just approach. Recognizing the limitations of existing urban planning frameworks in addressing both rapid urbanization in general and climate-induced migration in particular, policymakers must prioritize inclusive urban development through proactive and comprehensive policies that benefit both rural and urban communities. To effectively manage climate migration, governments must implement integrated, equitable, and forward-thinking strategies firmly grounded in the principles of climate justice:
- Equity and inclusion: Urban development policies must prioritize vulnerable groups, including women, children, and those in informal settlements. Climate adaptation funds should be directed to improving housing, water, and sanitation in underserved areas, creating a foundation for resilience. Furthermore, implementing targeted livelihood training programs tailored to the specific skills and needs of climate-displaced populations is crucial for their successful integration into urban economies.
- Participatory governance: Meaningful engagement with affected communities is essential for effective planning and decision-making. Establishing local participatory platforms empowers migrants to actively participate in selecting relocation sites, designing support programs, and shaping urban development initiatives that directly affect their lives. This inclusive approach ensures that policies are responsive to the needs and priorities of those most impacted by displacement.
- Climate-responsive urban planning: Integrating climate projections into urban development planning is paramount for anticipating future population pressures and mitigating environmental risks. This includes developing climate-resilient zoning regulations and contingency funds to support infrastructure upgrades and climate-proofing in high-risk urban areas is also essential for building long-term resilience.
- Rights-based accountability: Protecting the human rights of climate-displaced populations must be a central tenet of all policies and interventions. This includes ensuring access to adequate shelter, healthcare, education, and other fundamental rights. Independent, rights-based audits of relocation and urban development projects are essential for monitoring compliance with international human rights standards and ensuring accountability.
- Decentralizing local governance: While decentralization is a frequently discussed concept in Bangladesh, its implementation remains hindered by political constraints and the central government's reluctance to delegate authority. Without genuine and meaningful fiscal autonomy and decentralized decision-making, local governments cannot effectively address urban climate resilience. Empowering local institutions with financial and administrative autonomy, fostering direct international collaborations, and strategically investing in smaller cities to reduce the strain on major urban hubs are critical steps. Additionally, Flexible labour policies for migrants, addressing root causes of migration, and ensuring legal protections for climate-displaced persons are equally vital.
However, a critical challenge lies in the lack of reliable data. Without accurate and comprehensive data, it is nearly impossible to design or implement effective interventions. This gap is particularly evident in the fragmented efforts of NGOs, where overlapping initiatives often lead to inefficiencies and diluted impact. To address this, it is imperative to establish centralized data dashboards that track and analyze relevant metrics. NGOs working in specific fields need to operate under the umbrella of local governance structures, ensuring their efforts are coordinated and directed toward those most in need.
Beyond statistics
Climate migration is no longer a distant or abstract concern. It is a lived reality for millions worldwide. Urban systems are under immense pressure, rural livelihoods are eroding, and vulnerable populations -- face a cascade of insecurities. This is not merely an infrastructural crisis; it is a profound crisis of justice, equity, and human dignity, demanding a fundamental shift in our approach.
We must move beyond short-term measures and adopt integrated strategies that align climate adaptation, equitable urban development, and robust human rights protections to ensure that displaced populations can rebuild secure, dignified lives.
The time for action is long overdue.
Md Zahurul Al Mamun, Climate Change Researcher and Analyst. Uswatun Mahera Khushi, Assistant Professor, Local Government, and Urban Development, JKKNIU.
