This policy brief is based on a conversation with Julia Blocher, Project Lead at the Potsdam Institute for Climate Impact Research, and Andrea Milan, Head of the Mobility Data Lab at the Global Migration Data Analysis Centre of the International Organization for Migration.
Introduction
Rising global temperatures and severe weather events are increasingly factors driving both forced and voluntary migration. Internal Displacement Monitoring Centre (IDMC) statistics show that, of the 46.9 million individuals who moved internally during 2023, 26.4 million did so due to disasters.[1] Weather-related hazards such as floods and storms typically trigger the majority of disasters. However, 2023 saw a one-third reduction in displacements due to these disasters compared to 2022, partly because of the transition from La Niña to El Niño. Despite this decrease, weather-related hazards were still the main driver of displacement (20.3 million), followed by earthquakes and volcanic activity (6.1 million).[2]
Figure 1 — Internal Displacements in 2023: Breakdown by Hazard[3]
While there are many models to predict future displacement caused by climate change, their accuracy is a topic of debate within the field. Nevertheless, with an annual average of more than 20 million new displacements due to weather-related disasters, it is evident that climate-induced displacement is a pressing issue of our time, not just a concern for the distant future. Immediate government action is therefore crucial, as is a better understanding by the international community of the complexities surrounding the relationship between climate change and displacement.
To provide clarity on issues pertaining to climate-induced displacement, this brief addresses the following topics:
- What is climate mobility?
- Distinguishing between voluntary and forced migration.
- Challenges.
- Opportunities for growth.
What Is Climate Mobility?
According to the International Organization for Migration (IOM), climate-induced displacement refers to “the movement of a person or groups of persons who, predominantly for reasons of sudden or progressive change in the environment due to climate change, are obliged to leave their habitual place of residence or choose to do so, either temporarily or permanently, within a State or across an international border.”[4] Countries witnessing rapid population growth and wide exposure to natural disasters are likely to see increases in climate mobility, whether this is forced or voluntary outward migration, and regardless of duration.[5]
Researchers acknowledge that it is difficult to reliably establish a direct causal relationship between climate change and migration. Instead, each migration decision is the result of a nuanced combination of various factors. The Center for Climate and Security describes climate change as a threat-multiplier, whereby warming temperatures have the potential to exacerbate pre-existing threats and other drivers of instability, amplifying certain social, political, and economic discrepancies, all of which contribute to the likelihood of migration.[6] It is critical not to oversimplify the relationship between climate change and migration as direct and causal, because doing so may lead researchers to ignore the sociopolitical and economic conditions that also influence outward migration.
Distinguishing Between Voluntary and Forced Migration
Involuntary or forced migration tends to occur when sudden-onset disasters displace people in a relatively short amount of time and give them few options other than to migrate. These disasters, such as flash floods, cyclones, or hurricanes, generally affect large geographic areas. Disaster displacement is usually internal, and most internally displaced persons (IDPs) can return to their original homes within a year of displacement.[7] Displacement as a result of a sudden onset climate disaster does not usually take people very far and is not necessarily a long-term policy issue.[8]
Importantly, there are ways of mitigating the impact of such disasters, such as building defenses to protect against flooding, reinforcing infrastructure to protect against inclement weather, and investing in early warning systems to increase preparedness. Even so, the ability to prepare for sudden onset climate disasters varies greatly according to geographical context, which is why sudden events can lead to such high numbers of people becoming displaced in short periods of time. Additional risks arise when IDPs must cross international borders and cannot access the same legal status or protection opportunities available to refugees being displaced for reasons other than climate change.
While many policymakers may assume that the majority of climate-driven migration is forced — such as displacement after a flood or tornado — growing evidence illustrates that voluntary migration, which occurs when “migrants knowingly and willingly decide to leave their country and are able to enter another,” may also be affected by climate change.[9] Slow-onset climate change:
- Often occurs over longer periods of time.
- Is much more difficult to identify.
- Potentially leaves individuals more vulnerable than sudden-onset disasters.
The relationship between slow onset climate change and displacement is also less causal than sudden-onset manifestations. For example, rising sea levels can worsen the effects of flooding, land erosion can pollute waters and make soil less fertile, and drought can limit access to drinkable water and result in lower crop yields. Therefore, individuals choosing to migrate in search of better economic opportunities due to a decrease in agricultural productivity after long-term drought have likely been affected by climate change. In some cases, migrants may lack the language to express how climate change influenced their decision to migrate. In other cases, migrants may not attribute their decision to leave their home to climate change, instead viewing their preexisting vulnerabilities as the most pressing factor, even though their situation may not have been as severe without the effects of climate change.[10]
Nonetheless, distinguishing between forced and voluntary types of movements is not always easy. Voluntariness is conceived as a spectrum: On one end of the spectrum, individuals with greater capacities and ambitions to move will do so as they possess greater choice, while on the other end, those with more limited capacities are often left with no choice but to move, becoming involuntarily displaced or forced to migrate.
Challenges
Lack of Accurate Data and Reliable Models
One pressing challenge facing the international community is the lack of accurate data and reliable models to predict where individuals may migrate due to climate change or disasters. Because most current predictive models use data that is not disaggregated by basic factors such as age and sex, the findings are limited.[11] There is also a broader methodological issue — because migration is the outcome of highly context-specific interactions between a number of drivers, classic statistical methods struggle to accommodate this complexity. Without future-facing research that can better anticipate climate-induced displacement, crafting policy to meet the needs of displaced individuals is difficult.
Poor Migration Governance and Lack of Regular Migration Pathways
Another challenge arises from poor migration governance at both domestic and international levels and the lack of regular migration pathways for those displaced by climate change.
- The 1951 Refugee Convention and its 1967 Protocol — which form the backbone of the international system of refugee protection — do not extend legal status to individuals who have fled their home countries due to climate change or environmental disasters. This makes it unlikely that refugees will be able to receive international protection or claim asylum on account of climate disasters.
- At the regional level, several mechanisms and frameworks such as the Cartagena Declaration and the OAU Convention use broader definitions of refugees and displaced peoples who have the right to seek protection. In theory, they provide a higher chance of recognition for individuals displaced by climate change, but it has been difficult to assess their effectiveness in practice.[12]
Even without adequate protection mechanisms, understanding why climate is becoming an increasingly significant factor in migration decisions can influence policymaking and how individuals receive legal protection. The main barrier to expanding these protection mechanisms is the lack of political will due to widespread negative attitudes against migrants, as demonstrated by rising global nativist sentiments, especially in Western countries.[13]
Unequal Effects of Climate Change
The effects of climate change are also not felt equally. A recent report found that food insecurity, which can be amplified by climate change, has a particularly acute effect on marginalized groups, such as women or ethnic minorities.[14] The United Nations estimates that women and girls are 14 times more likely to die than men when extreme weather strikes.[15] Particularly in rural communities, where they have greater domestic responsibilities, women can be more exposed to gender-based violence when their responsibilities increase during times of climate crisis. If droughts plague a farm, women may have to walk further to secure water or spend more time collecting income to provide for their families. Another example is in the agricultural sector where women are frequently the majority of the workforce, but their contributions often go unnoticed.[16] This leads to the exclusion of women from decision-making spheres and their interests being underrepresented in policy formulation.[17]
Considering the socioeconomic strain that women and girls in climate-affected regions face, aid should more directly target women, seeking to alleviate or avoid these adverse outcomes. Moving forward, to reduce and prevent the disproportionate effects of climate change on women and girls, it will be crucial to integrate a gender perspective into both research and development work on climate-induced displacement.[18]
Opportunities for Growth
Despite clear challenges, there are actionable steps policymakers can take to improve the lives of individuals who migrate as a result of climate change. We recommend specific action in four policy areas:
1. Adapt to Climate Displacement by Expanding Regular Migration Pathways
Foreign governments can reframe climate-induced displacement as an adaptation strategy and increase the availability and flexibility of pathways for regular migration.[19]
Examples:
- Tuvalu and Australia signed a bilateral deal guaranteeing a set number of migrants from the small island nation the ability to relocate to the latter. The success of this agreement provides a promising model that other countries can emulate.[20]
- Other nations such as the United States have used temporary protected status for those unable to return home — although it only applies to those already present in the U.S. — and subsidiary protection programs are also present in many European countries.[21]
- A special humanitarian visa in Argentina facilitates the regular admission of individuals from Central America, Mexico, and the Caribbean who are fleeing socio-natural disasters, a type of visa that could be implemented by other countries.[22]
Importantly, individuals do not necessarily define themselves as “climate migrants.” Therefore, safe pathways for migrants need to be expanded overall.
2. Improve Modeling and Data To Predict Migration
Researchers, governments, and other stakeholders can work together to improve modeling and data to understand where and when migration is likely to take place. Despite the current challenges around data and modeling, improvements are happening rapidly and data is becoming better, more available, and more spatially precise. The IOM — a leader in this area — recommends building more advanced datasets based on specific geographic regions, socioeconomic conditions, and community resilience, which will enable modeling to move beyond antiquated worst-case scenario assumptions to more accurately predict human movement. Researchers can look beyond classical statistical methods to build models that reflect the complexity of decision-making surrounding migration. Designing collaboratively with governments may allow models to better incorporate potential policy decisions. These improvements would allow aid agencies, private companies, and governments to respond to migration by advancing and building systems that work for individuals, as well as state and non-state actors.
3. Increase the Role of Diaspora Philanthropy
Non-governmental actors also can play an important role in the policy arena. Diaspora philanthropy is an emerging area of charitable giving in the context of climate change, in which diasporas focus on building resilience projects and investing in areas back home, thereby strengthening communities affected by disasters or slow-onset impacts.[23] By decreasing barriers to sending remittances from family members or acquaintances, financial organizations and governmental actors can further facilitate this trend.
4. Improve Overall Climate Resilience
Enhancing overall climate resilience can enable individuals to choose migration voluntarily, rather than being forced to do so. Climate resilience can be improved through national and international efforts, particularly through climate adaptation funding such as the Green Climate Fund or the Adaptation Fund. The Loss and Damage Fund operationalized at COP28 included the term “human mobility” for the first time — the $700 million pledged so far for that fund shows that some progress is being made.[24]
Conclusion
Individuals will continue to migrate, and as climate change worsens and its effects become more pronounced, they will do so at increasing rates. Whether voluntary or involuntary, climate-induced displacement presents both challenges and opportunities for the international community to ensure cohesion in the face of climate disasters and safety for those who choose to move. Despite current modeling limitations, advances in research point toward the possibility of better predictions in the future. Meanwhile, countries should continue to adopt innovative protection schemes for individuals moving due to climate change. These approaches, paired with diaspora philanthropy and temporary protection mechanisms, present promising examples of how stakeholders at different levels and in various geographic areas can respond to climate-induced displacement.
Notes
[1] Internal Displacement Monitoring Centre (IDMC), 2024 Global Report on Internal Displacement (GRID 2024), accessed May 30, 2024, https://api.internal-displacement.org/sites/default/files/publications/documents/IDMC-GRID-2024-Global-Report-on-Internal-Displacement.pdf.
[2] GRID 2024.
[3] GRID 2024.
[4] “Environmental Migration,” International Organization for Migration (IOM), accessed May 30, 2024, https://environmentalmigration.iom.int/environmental-migration.
[5] Lucy Szaboova and Cristina Colón, “Concepts, Contexts and Categorizations of Climate Mobility,” United Nations International Children’s Emergency Fund (UNICEF), June 2021, https://www.unicef.org/innocenti/reports/concepts-contexts-and-categorizations-climate-mobility.
[6] Sherri Goodman and Pauline Baudu, “Climate Change as a ‘Threat Multiplier’: History, Uses and Future of the Concept,” Center for Climate and Security, January 3, 2023, https://councilonstrategicrisks.org/wp-content/uploads/2023/01/38-CCThreatMultiplier.pdf.
[7] Lawrence Huang, “Climate Migration 101: An Explainer,” Migration Policy Institute, November 16, 2023, https://www.migrationpolicy.org/article/climate-migration-101-explainer#.
[8] Szaboova and Colón.
[9] IOM, “The Global Concept of International Migration: Types of Movements,” accessed May 30, 2024, https://emm.iom.int/handbooks/global-context-international-migration/types-movements-0.
[10] Szaboova and Colón.
[11] Robert Beyer and Andrea Milan, “Climate Change and Human Mobility: Quantitative Evidence on Global Historical Trends and Future Projections,” IOM, June 5, 2023, https://www.iom.int/resources/climate-change-and-human-mobility-quantitative-evidence-global-historical-trends-and-future-projections.
[12] Ana Martín Gil, Pamela Lizette Cruz, Kelsey Norman, and Ivonne Cruz, “How Can We Protect ‘Climate Refugees’?” (Houston: Rice University’s Baker Institute for Public Policy, October 13, 2022), https://doi.org/10.25613/VZ6N-FF86.
[13] Jeffrey Mitchell, “Social Trust and Anti-immigrant Attitudes in Europe: A Longitudinal Multi-Level Analysis,” Frontiers in Sociology no. 6, art. 604884 (2021), https://doi.org/10.3389/fsoc.2021.604884.
[14] Uzra Zeya, “The Intersection between Climate Change, Food Security, Migration and Displacement,” Department of State, November 29, 2022, https://www.state.gov/the-intersection-between-climate-change-food-security-migration-and-displacement/.
[15] United Nations, “Why Women Are Key to Climate Action,” accessed May 30, 2024, https://www.un.org/en/climatechange/science/climate-issues/women#:~:text=When%20extreme%20weather%20disasters%20strike,change%20are%20women%20and%20girls.
[16] EmPower, “Climate Change and Women in Agriculture,” accessed May 30, 2024, https://www.uncclearn.org/wp-content/uploads/library/02-issue-brief_climate-change-and-women-in-agriculture.pdf.
[17] EmPower.
[18] Giovanna Gioli and Milan, “Gender, Migration and (Global) Environmental Change,” in Routledge Handbook of Environmental Displacement and Migration, edited by Robert McLeman and François Gemenne (London: Routledge, 2018), 135–50, https://www.taylorfrancis.com/chapters/edit/10.4324/9781315638843-11/gender-migration-global-environmental-change-giovanna-gioli-andrea-milan.
[19] François Gemenne and Julia Blocher, “How Can Migration Support Adaptation? Different Options to Test the Migration–Adaptation Nexus,” Working Paper Series no. 1/2016, IOM, December 6, 2016, https://publications.iom.int/system/files/pdf/working_paper_series_1.pdf.
[20] Kirsty Needham, “Australia Signs Security, Migration Pact with Pacific’s Tuvalu,” Reuters, November 10, 2023, https://www.reuters.com/world/asia-pacific/australia-offer-climate-refuge-all-residents-tuvalu-report-2023-11-10/.
[21] Diana Roy and Claire Klobucista, “What Is Temporary Protected Status?,” Council on Foreign Relations, September 21, 2023, https://www.cfr.org/backgrounder/what-temporary-protected-status.
[22] Martín Gil, P.L. Cruz, Norman, and I. Cruz.
[23] Kathleen Newland, Aaron Terrazas, and Roberto Munster, Diaspora Philanthropy: Private Giving and Public Policy (Washington, DC: Migration Policy Institute, 2010), https://www.migrationpolicy.org/research/diaspora-philanthropy-private-giving-and-public-policy.
[24] United Nations Climate Change, “COP28 Agreement Signals ‘Beginning of the End’ of the Fossil Fuel Era,” press release, December 13, 2023, https://unfccc.int/news/cop28-agreement-signals-beginning-of-the-end-of-the-fossil-fuel-era.
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