Awareness has grown of the intimate link between climate change and migration in past years but it remains a complex and contentious issue. In a debate fanned by the media and populist politicians, University of Liège researcher Caroline Zickgraf separates myth from reality. Explaining how our changing environment is making people move, she calls for evidence-based preparation rather than fear-based reactions and crisis responses. As climate change escalates, such understanding is a first step on the way to a much-needed political response.

The global impacts of climate change threaten to reshape the world in a dramatic fashion. From sea level rise, coastal erosion, land degradation, droughts, floods, and temperature increase to intensifying and more frequent storms, any number of detrimental impacts caused by a rapidly warming planet fundamentally changes how and where we live. Sudden-onset events and slow-onset processes combine to damage and destroy homes and assets, decrease crop productivity and biodiversity, forcing people from their lands and livelihoods. While some people are forced to flee in a rapid fashion, others move preemptively or in response to the gradual changes that make living – and earning – in situ ever more difficult, forming a complex spectrum of human mobility related to climate change.

This article intentionally takes a rather wide view of this spectrum, in order to tackle some of the most common questions about how migration and climate change collide – and what should be done about it.

What do we call them?

Discussions on the relationship between migration and climate change often falter at the first step: people do not agree on what to label it and who qualifies for such labeling. In the initial days of raising awareness of the issue, environmental activists and organisations likened the plight to that of conflict asylum seekers and refugees, birthing the terms ‘environmental’ or ‘climate refugees’. In 1985, the first official mention of ‘environmental refugees’ appeared in a UN Environmental Programme report. Undoubtedly, this naming brought with it an urgency in tone ideal for calling attention to a nascent issue (not in occurrence but in visibility). Rather quickly, however, refugee and forced migration (especially legal) experts piped in: simply put, these people are not refugees. The 1951 Geneva Convention Relating to the Status of Refugees makes no mention of environmental disruption or climate change. It is a misnomer but also, many argued, dilutes the meaning of refugee. In 1997, Gaim Kibreab, a refugee studies scholar, stated that the term served to ‘depoliticise the causes of displacement’ so that states would not be obliged to provide asylum.1 Others argued that ‘climate refugee’ diminishes the agency of people and also that it obfuscates the multi-causality of migration, i.e. it is never ‘just’ climate change. Climate change is a threat multiplier; it cannot be isolated from social, political, economic, environmental and demographic migration drivers. Lastly, it places a singular label on an extremely diverse phenomenon.

A back-and-forth ensued and many became gun-shy to use the highly contested ‘climate refugee’. They instead came up with a host of more nuanced, but also diluted, terms (e.g. migration in contexts of environmental change) or specific terms that steered clear of the refugee label (e.g. climate migrants, climate displaced persons, disaster displaced). Several international organisations, NGOs, advocacy groups, and activists plowed on with climate refugee, either unaware of the emerging scientific taboo and/or because they thought the forced nature of movement warranted the refugee label and underscored its humanitarian implications.

So where do we stand today? The short, but admittedly unsatisfying, response is that we have yet to reach any consensus in name or definition. Academics, politicians, activists, and other actors employ many labels, sometimes interchangeably, but there is still a taboo around using climate refugee. This goes hand-in-hand with the fact that there is no consensual definition. In 2007 the International Organization for Migration put forth a rather broad suggestion to cover a range of relationships between environment and migration,2 but that has never been universally adopted. Many a roundtable and panel are convened to rehash these debates, but faced with growing terminological fatigue, many actors now argue that political and humanitarian action do not require a single, agreed upon name or definition. Action is more important than words.

How many?

Much of the discourse on climate and migration is what academics Andrew Baldwin, Chris Methmann and Delf Rothe call ‘futurologies’. That is to say, it’s about what will happen in the future if nothing, or not enough, is done to prevent further climatic change. Perhaps the most evident of this are frequently cited estimates of (potential) future migration. These numbers have been highly influential in the media, but also in political circles. Yet, the quantitative predictions regarding future migration flows vary widely in amount and methodology. Alongside terminology, numbers have become one of the most debated topics in the field. In 2002, Norman Myers warned that as many as 200 million people could be displaced, “overtaken by sea-level rise and coastal flooding, by disruption of monsoon systems and other rainfall regimes, and by droughts of unprecedented severity and duration.”3 Through wide-spread repetition, this highly speculative figure is often taken for fact. However, this and many other past numbers of how many people will move because of climate impacts or environmental disruption were more or less guestimates, often based on a deterministic assumption that if we count the number of people living in a vulnerable area, factor in population growth by 2050, then you’ve got your number of future climate migrants. In some cases, these figures reach 1 billion! As pointed out by scholar François Gemenne, Director of the Hugo Observatory at the University of Liège, the first scientific research center dedicated to the environment-migration nexus, many of the forecasts generated in the 1990s and 2000s were united by common features: they were received with great skepticism by scholars, but welcomed with great interest in media and policy circles.

Scientific assessments are certainly improving, with better modelling techniques and rigorous efforts to project more accurate, evidence-based ranges of population movements. A 2018 World Bank report estimated that – without urgent action – up to 143 million people could become internal climate migrants (moving within their countries) in Sub-Saharan Africa, Latin America and South Asia by 2050. Still, the 2019 Intergovernmental Panel on Climate Change (IPCC) Special Report on Oceans and Cryosphere noted that while there is high agreement that climate change has the potential to drastically alter the size and direction of migration, there is low confidence in quantitative projections of migration. Future migration and displacement that is driven by the impacts of climate change will largely come down to the mitigation and adaptation measures we take.

Importantly, we do not have a global figure for how many people are currently on the move owing (at least in part) to the impacts of climate change and other forms of environmental degradation. What we do know is that disasters are displacing millions worldwide. The Internal Displacement Monitoring Centre estimated that 17.2 million people were internally displaced by disasters in 2018 alone. By way of comparison, 10.8 million were newly displaced by conflicts in the same year. But no global figure accounts specifically for all climate impacts and all types of migration currently underway (including more economic and voluntary forms of migration). Beyond global figures, local, national, and regional data gaps are persistent challenges for actors seeking evidence-based solutions.

Are ‘they’ coming to Europe?

Certainly, numbers can grab people’s attention in a way that ‘it depends’ or ‘it’s complicated’ cannot. However, focusing on figures exclusively obscures the many impacts of climate change on migration that go beyond volume of movement, for instance temporality, agency and distance. Where people do and will go is certainly a critical question for policy response to climate change and migration. Based solely on documentaries and news reports in Western media, one could not be faulted for thinking that people are migrating en masse out of the world’s most vulnerable regions (environmentally and socio-economically) in the Global South, and towards the countries of the Global North. When the Global North steers narratives, it unsurprisingly tends to focus on their particular concerns, i.e. how does this affect ‘us’? From a European perspective, climate migration readily conjures images of overcrowded boats crossing the Mediterranean Sea. A 2010 Museum of London exhibit called ‘London Futures’: ‘Postcards from the Future’ digitally transformed the capital’s landmarks to show what the city could look like in a world of climate change. Drawing on Kenyan and Moroccan influences, two startling images depict Nelson’s Tower and Buckingham Palace surrounded by shantytowns of so-called ‘climate refugees’. This, unsurprisingly, didn’t go over well.

The ‘threats’ of masses of people from developing countries landing on European shores are simply not based on current scientific evidence, and thus do little to promote evidence-based policy decisions rather than fear- (and prejudice-) based reactions. In fact, science suggests that when faced with the impacts of climate change most people tend to migrate within their countries. Internal migration and displacement may indeed lead to international movements, but it is unlikely that those people who are forced or who choose to leave particularly vulnerable climate areas will all be able to make the journey to Europe – nor do they all want to. Migration, and especially international long-distance migration, takes means – such as money, social networks, skills, visas, and even physical ability to move. With climate change impacts, we see an increase in migration out of some areas, but we also see a decrease in out-migration in others. As put forth by a 2011 seminal report on environmental change and migration, the UK Foresight Report, “Environmental change is equally likely to make migration less possible as more probable.” A decrease or stagnation in migration is not necessarily, therefore, something to celebrate. It can denote a growing, and largely invisible, vulnerable population: those that are in danger but unable to get out. When this happens, the humanitarian implications have the potential to be enormous.

Furthermore, climate mobility is not the exclusive ‘problem’ of the Global South. Coastal erosion, flooding, hurricanes and storms are already displacing people in North America and Europe. Although it’s often articulated as an issue for a distant other, with disasters growing in intensity and frequency European populations will also face the consequences. A new modelling tool developed by the Internal Displacement Monitoring Centre estimates an average of 15 000 people will be displaced by floods in Spain annually, in France more than 28 000. Europe needs to prepare and plan for its own internal and intra-continental migration and displacement.

How do we solve climate migration?

The common implicit undertone in media, public and policy debates is that climate-related migration is an inherently bad thing. People forced to move because of the impacts of climate change is by no means a positive outcome of the continued rise of global greenhouse gas emissions. Climate impacts forcing people to flee their lands, livelihoods and assets is a massive challenge facing an increasing portion of the world’s population. However, looking at migration as an inherent problem that needs to be ‘solved’ overlooks the diversity of migration and its benefits. Not all movements related to climate change occur due to force (i.e. displacement). In some cases, (relatively) voluntary migration is just one of a host of adaptation strategies in place to respond to environmental change, whether it is temporary, circular, seasonal or permanent, a strategy which is undertaken by choice and can have positive outcomes. Migration need not be the strategy of last resort.

Pre-emptive, voluntary migration, in fact, can be a part of the solution to adapt to the impacts of climate change, and to help reach the stated goals of the Paris Agreement: to address, avert, and minimise future displacement.4 When crop productivity decreases, or natural resources deplete, people moving away from harm can be beneficial to migrants, to their communities of origin and to their destination communities (whether within their countries or in other countries). At the same time that migrants need to escape physical and economic harm, and ultimately better their living conditions and opportunities, communities of origin can benefit from the financial and social remittances that may result. Such remittances can lead to the construction of more disaster-resilient homes, improve education, assist in local adaptation projects, and decrease dependence on local, natural resource-dependent livelihoods, for example. Destinations can also gain from in-migration when it is well managed and when people are integrated into local societies. They can solve problems of an aging population, i.e. ‘greying’ Europe, boost entrepreneurship and stimulate stagnating economies, and bring new skills and perspectives to local challenges. Ultimately, this can lead to a ‘triple-win’ scenario: for migrants, for communities of origin and for destination communities.

Planning and preparing for migration for sending communities and destination communities is critical to realise and maximise the beneficial potential of migration. Just as disaster risk reduction is preferable to post-hoc disaster responses, facilitating migration in safe, orderly, and regular ways can decrease the risks for displacement and ad hoc and crisis responses in situ. Several Pacific Island governments are developing a range of plans, including international migration and relocation strategies. In the Republic of Kiribati, where two-thirds of its land is less than two meters above sea level, the government developed the ‘Migration with Dignity’ policy. It aims to improve education and skills training for its citizens in order to facilitate voluntary temporary and permanent labor migration to nearby countries like New Zealand as a long-term adaptation measure. In other countries such as Viet Nam, Sierra Leone and Fiji, municipal and national governments are implementing or proposing the planned internal relocation of vulnerable villages and communities, taking a more drastic migration-as-adaptation approach.

Time will tell to what extent a world of climate change will be a world on the move. Climate action – both adaptation and mitigation measures – will undoubtedly shape human mobility dynamics. International policy fora such as the UN Framework Convention for Climate Change (UNFCCC) are increasingly aware of this, as signaled by the creation of such platforms as the Task Force on Displacement, established through the Paris Agreement in 2015, and the Platform on Disaster Displacement. Tackling these issues does not, however, stop at the international level. It requires coherent multi-scalar governance, including bottom-up local policies and programmes catered to local realities.

Preventing displacement and maladaptive migration also demands dialogue and action that stretch across our traditional policy silos: climate, environment, migration, development, etc. At the EU-level, this means coordination across relevant Directorate-Generals, but also coordination between EU and member states. For example, both the EU and its members can make actionable commitments to implement the recent Global Compact for Safe, Orderly and Regular Migration, whose second objective is to address adverse drivers and structural factors that compel people to leave their country of origin, including deteriorating environmental conditions. The EU can also explicitly consider migration within climate financing, its development policies, and the European Neighborhood Policy. EU and member state migration policies should also take climate change into account, for example through bilateral labour mobility agreements with climate-affected countries, or by providing humanitarian visas for displaced populations.

In short, migration policies should address climate change, including the facilitation of migration for the most vulnerable, while environmental policies need also address their impacts on migrants. Such holistic efforts can help protect the displaced, support self-determination, and address the vulnerabilities of those who stay as well as those who go.


1. Kibreab, G. (1997). Environmental Causes and Impact of Refugee Movements: A Critique of the Current Debate. Disasters, 21(1), 20–38. Available at <>.

2. “Environmental migrants are persons or groups of persons who, predominantly for reasons of sudden or progressive change in the environment that adversely affects their lives or living conditions, are obliged to leave their habitual homes, or choose to do so, either temporarily or permanently, and who move either within their country or abroad” (IOM, 2011:33). See <>.

3. Myers, N. (2002). Environmental refugees: A growing phenomenon of the 21st century. Philosophical Transactions of the Royal Society B: Biological Sciences, 357 (1420), 609–613. Available at <>.

4. Decision 1/CP.21, paragraph 49.

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