Climate change is displacing millions, exposing a growing crisis of responsibility, protection, and climate justice. Photo by Li-An Lim on Unsplash
Should climate displacement be treated as a justice issue, not merely a humanitarian one?
Climate change is reshaping how and where people can live. Increased frequency and severity of flooding, wildfire, drought, and land degradation have significant effects on the displacement of people worldwide. Evidence from the United Nations High Commissioner for Refugees (UNHCR) shows that both sudden and slow-onset environmental changes are forcibly displacing millions of people each year, causing a loss of homes, livelihoods, and culture. This raises some key questions: who is responsible for preventing displacement and for protecting those affected? Does responsibility lie not only with the national governments of countries in which displacement occurs, but also with historically high-emitting states whose actions have disproportionately created these conditions? Should climate displacement be treated as a justice issue, not merely a humanitarian one? I argue that climate displacement is driven by both short- and long-term effects of climate change, that current legal protections for climate-displaced communities are insufficient, and that high-emitting states bear significant policy responsibility for adapting to and mitigating climate displacement.
To clarify what I mean by climate displacement, I draw on Ayesha Tandon’s 2024 article in Carbon Brief, which covers developments in climate science and policy. In ‘How does climate change drive human migration?’, Tandon explains that ‘“displacement” is the term used when people are forced to flee their homes—often suddenly—for example when faced with an extreme flood or storm’, while ‘“migration” describes a decision to move in search of a better quality of life, often after years of deteriorating quality of life.’ I believe this distinction is important both politically and legally, as displacement can trigger protection obligations under international law, while migration often does not.
…slow-onset changes that cause lifestyles to become unsustainable can also push people into displacement.
Climate change drives displacement through both sudden disasters and slow-onset environmental degradation. According to the UN, sudden events such as floods and wildfires temporarily displace millions of people each year. But slow-onset changes that cause lifestyles to become unsustainable can also push people into displacement. As Lawrence Huang, Policy Analyst at Migration Policy, writes, climate impacts such as ‘sea-level rise, land degradation, coastal erosion [and] extreme temperature’ can render entire areas, and entire islands, unliveable. These gradual threats amplify existing displacement risks, particularly where institutional, political and socio-economic vulnerabilities already exist. I argue that climate change therefore does not simply catalyse movement; it removes choices and intensifies displacement pressures, which is why both sudden and slow-onset climate displacement must be understood as involuntary.
Historically, sudden disasters often caused temporary displacement, with people moving locally and returning when possible. But the increased frequency and duration of climate-related disasters is making their return increasingly unviable. Meanwhile, slow-onset changes are worsening health inequalities and poverty, degrading ecosystems, and in some cases permanently submerging land, forcing communities into permanent displacement.
The “binary” distinction between sudden extreme events and slow-onset disasters is blurring as each compounds the other. There is an increasing frequency and severity of climate-related catastrophic events, that compound ongoing ecological vulnerability, which in turn makes the damage suffered from each disaster worse. Heatwaves and wildfires, for example, can cause long-term damage to land resilience, leaving communities more vulnerable to future extreme events. Climate displacement is therefore rarely attributable to a single event; instead, I believe, multiple impacts of climate change—both sudden and slow-onset—act on each other as “risk multipliers” that compound the effects on habitats and drivers of displacement.
The World Bank estimates that up to 216 million people could be internally displaced by 2050 under the worst-case warming scenarios, though this figure could fall dramatically with effective mitigation and adaptation policies. I believe that policy choices matter: displacement is not an inevitable tragedy for vulnerable communities, but a failure to act early and adequately will push people into involuntary displacement.
Climate displacement disproportionately affects the world’s most vulnerable populations.
Climate displacement disproportionately affects the world’s most vulnerable populations. The UNHCR writes, ‘Over 70% of refugees and displaced people originate from the most climate-vulnerable countries, including Afghanistan, the Democratic Republic of the Congo and Yemen.’ Communities in these places face deepening challenges from environmental degradation: ‘three-quarters of Africa’s land is deteriorating’, placing displaced communities under serious ecological stress because of reduced access to food, water, and income. These regions contribute least to global emissions yet face the most severe impacts, often compounded by political, institutional, and economic stresses. I believe that examining climate displacement without acknowledging these inequalities risks misattributing responsibility, allowing historically high-emitting states to treat displacement as a problem for affected countries alone.
Climate change is not only increasing the number of displaced people but also making displacement more dangerous. Since 2009, the number of countries experiencing both conflict and disaster-related displacement has tripled. In Brazil’s 2024 floods, over half a million people were displaced, including tens of thousands of refugees already living in highly vulnerable areas. In Africa’s Sahel region, where there are nearly four million displaced people, rising temperatures and land degradation are intensifying competition over food and water, fuelling conflict that further endangers these displaced communities. Climate change can also trap people in place by depleting the resources needed to move, creating “immobile” populations exposed to extreme risk. I argue that when people cannot escape danger on their own, government inaction becomes a form of active harm.
Climate change is creating new challenges for international law by blurring the line between displacement and migration. As Tandon’s definition suggests, displacement traditionally implied sudden forced movement, while migration suggested some degree of choice. Climate change disrupts this distinction: the pressures to move described above may build slowly, but displacement is involuntary without liveable alternatives.
…the pressures to move described above may build slowly, but displacement is involuntary without liveable alternatives.
Despite growing evidence of climate displacement, international law has not kept pace. The 1951 Refugee Convention does not recognise climate-related harms as grounds for refugee status, leaving many displaced communities without formal protection. Although human rights law offers some safeguards through the principle of non-refoulement, preventing return where serious harm is likely, courts have not definitively ruled that returning someone to a climate-disaster zone is unlawful. To me, this legal gap matters, because if climate-displaced people are treated as irregular migrants (i.e. people who do not fulfil the requirements established by the country of destination to enter, stay, or exercise an economic activity) rather than rights-holders, high-emitting states can prioritise deterrence and returns over protections and resettlement. Legal protections must be expanded to protect climate displaced people.
Responsibility for climate displacement cannot be separated from historical emissions. When colonial-era emissions are included, countries such as the UK and the Netherlands rank among the highest cumulative emitters per capita. Justice therefore demands more than emissions reductions; it requires recognition of historical contributions, financial and policy responsibility for adaptation, mobility and protection, and expanded legal protections. Proposed responses include climate finance, such as the UNHCR’s Climate Resilience Fund, or expanded migration pathways, for example the UK’s Displaced Talent Mobility Pilot, although this pathway only accepted already highly skilled individuals. While reparations or relocating can never fully compensate for the loss of home or culture, I argue that refusing to engage with responsibility of support only perpetuates injustice and apathy.
There are emerging examples of more constructive approaches. In November 2023, Australia and Tuvalu announced the Falepili Union treaty, allowing up to 280 Tuvaluans per year to migrate to Australia with access to healthcare, education and employment. About one-fifth of Tuvalu’s population has already left the island permanently. Similar leadership could be shown by the UK and Europe, though current EU approaches remain dominated by deterrence and border militarisation, despite the rapid expansion of free movement for Ukrainian refugees in 2022.
…addressing climate displacement requires recognising historical emissions and taking responsibility for them, expanding legal protections, and creating safe, dignified pathways for movement caused by climate change.
Government inaction on climate change infringes on a wide range of human rights, including the rights to life, dignity, health, food, water, housing, and a clean and sustainable environment. Climate change’s multi-dimensional role in driving displacement forces us to confront difficult questions about responsibility, borders and justice. The evidence shows that displacement is driven by identifiable actions, affects predictably vulnerable populations, and can be reduced through mitigation and adaptation. Yet current responses focus on emergency relief and restrictive border control rather than long-term responsibility-sharing. I think that addressing climate displacement requires recognising historical emissions and taking responsibility for them, expanding legal protections, and creating safe, dignified pathways for movement caused by climate change. Without these changes, I believe that climate displacement will continue to rise, and with it, the human, economic, and moral cost of inaction.
