Climate change is affecting global migration

This post is part of my M.Sc. CCAFS thesis titled “Climate-Related Migration and the Climate-Migration Security Nexus in the Dry Corridor of Central America” in conjuncture with the CGIAR.

Globally, climate change is setting new records for phenomena such as heatwaves, droughts, wild fires, and a increased frequency of natural disasters (e.g., hurricanes, floods) year after year. Consequently, alarmist narratives speaking of hundreds of millions of so-called “climate refugees” in the coming decades have been employed by a variety of actors with different agendas. On the one hand, depictions like this are used to stress the dire need of immediate and effective measures for climate change mitigation. On the other hand, they have also been instrumentalised by many to call for border fortification in an order to limit migration and protect wealth. These narratives of “climate refugees” have been rightfully criticised for their oversimplification of a process as complex as migration and also for depicting those affected by climate change as passive victims without agency while also disregarding other migration drivers which are simultaneously at work, such as conflict and violence, poverty and inequality, or political and social exclusion.

While the notion of climate-related migration remains contested, it is indisputable that climate change does have an effect on migration. Human mobility, the umbrella term referring to all aspects of the movement of people, as also noted in the UNFCCC Paris Agreement, can take on different forms. This includes internal as well as cross-border (international), voluntary and involuntary, and seasonal, temporary or permanent movements. The outcome of who engages in what kind of mobility is highly context-specific, however, some generalisable observations have emerged:

1). Despite the focus of attention is on international migration and more specifically South-North migration, most climate-related migration will be internal. Internal migration, mostly headed toward urban areas, requires less (financial) resources and are less socially and culturally disruptive. Urbanisation rates are particularly high in the Global South, where the overall population is growing rapidly and climate change resilience is comparatively weak. Urban governance systems are often overwhelmed and do not have the capacity to accommodate the basic needs (e.g., shelter, food, employment, security) of rapidly growing populations. Among the results are informal settlements, highly vulnerable against climate impacts, further impoverishment, and conflict.

2). Rather than a direct causal correlation, climate change impacts human mobility outcomes by its impact on a broad range of socioeconomic variables, such as poverty (e.g., by reducing income), inequality (e.g., by deepening gender inequality), and conflict (e.g., by reducing assess and availability of natural resources). Migration is not to be explained monocausally but rather as an result of an interplay between economic, social, political, cultural, and environmental factors. Commonly, climate change exacerbates preexisting vulnerabilities and thus constitutes itself as a “threat multiplier”, which goes on to effect whether and what kind of migration is engaged in and if it can act as an adaptation strategy for households.

3). While slow-onset climate change impacts such as sea level rise, desertification, and land and forest degradation often trigger permanent or long-term relocation, rapid-onset impacts such as storms and floods tend to lead to short-term relocation, allowing for a potential return. However, as climate change further processes, slow-onset impacts unfold, eventually surpassing individual or collective thresholds influencing the decision to migrate. Similarly, rapid-onset impacts are projected to occur far more frequently as well as severely.

4). A common pathway of climate change affecting migration is via the link of agriculture. As climate and weather become more erratic and unpredictable and climate change shortens planting seasons, yields and incomes decline. About 80% of farming around the world is rain-fed and thus highly sensitive. Smallholder farmers depend on farming for their daily income and, in the case of sustenance farming, for their food. A growing number of rural households engage in (seasonal) labour migration, in which one or several household members add to the household income by sending remittances. These serve as a income diversification and informal insurance strategy to limit the impact of climate shocks and are also used to build-up in-situ climate change adaptation. However, a result can also be distress migration. This may the case in instances of severe food insecurity, with a potential consequence being further impoverishment and vulnerability, particularly in cases of irregular migration.

5). Climate change is projected to increase human mobility, however, it simultaneously is projected to increase human immobility. Due to lack of resources and financial capital, also impacted by climate change, populations of climate risk-prone areas might not be able to relocate. This would have severe implications for resource-constrained households, leaving them extremely vulnerable to subsequent climate change impacts, poverty, and food insecurity.

Crucially, important policy documents like the Paris Agreement acknowledge that “the movement of people is intrinsically linked to climate change” Similarly, the UN Compact for Safe, Orderly and Regular Migration emphasises the urgency to reduce involuntary climate-related migration. However, and despite the growing evidence entangling the interrelationship between climate change and migration, on an international level, these good intentions are fare from being matched in practice as there is little interest to give a formal status or legal recognition to those moving for climate-related reasons. It will be essential to include climate-related migration into international and legally-binding documents and to implement migration into climate change policies.

Check out the video below for a visualised summary of the connections between climate change and migration.

Sources & additional information:

• Black, R., Adger, W. N., Arnell, N. W., Dercon, S., Geddes, A., & Thomas, D. (2011). The effect of environmental change on human migration. Global Environmental Change, 21, S3-S11.
• Cai, R., Feng, S., Oppenheimer, M., & Pytlikova, M. (2016). Climate variability and international migration: The importance of the agricultural linkage. Journal of Environmental Economics and Management, 79, 135-151.
• Ferris, E. (2020). Research on climate change and migration where are we and where are we going? Migration Studies, 8(4), 612-625.
• Gemenne, F., & Blocher, J. (2017). How can migration serve adaptation to climate change? Challenges to fleshing out a policy ideal. The Geographical Journal, 183(4), 336-347.
• Maurel, M., & Tuccio, M. (2016). Climate instability, urbanisation and international migration. The Journal of Development Studies, 52(5), 735-752.
• McLeman, R. (2018). Thresholds in climate migration. Population and Environment, 39(4), 319-338.
• McLeman, R., & Gemenne, F. (2018). Routledge handbook of environmental displacement and migration. Routledge London/New York.
• Piguet, E., Pécoud, A., & De Guchteneire, P. (2011). Migration and climate change: An overview. Refugee Survey Quarterly, 30(3), 1-23.
• Rigaud, K. K. d. S., Alex; Jones, Bryan; Bergmann, Jonas; Clement, Viviane; Ober, Kayly; Schewe, Jacob; Adamo, Susana; McCusker, Brent; Heuser, Silke; Midgley, Amelia. (2018). Groundswell: Preparing for Internal Climate Migration.