Climate-driven migration: an inevitable future?

The number of people exposed to climate risks is rising constantly due to an overall increase in the world’s population and in climate-related risks. Sea-level rise is already causing serious problems for many of the world’s largest conurbations, which are not only located in coastal areas but also experiencing strong population growth. Densely populated deltas of major rivers in low- and medium-income countries are also under pressure from sea rise. Moreover, climate irregularities and gradual changes alike have a particularly strong impact on people who make a living in activities like farming and animal husbandry that depend heavily on weather conditions. 

Increasing exposure to risk goes together with increasing vulnerability due to persistent economic inequalities and relatedly unequal living conditions, particularly in connection with housing and health. Populations living in states with neither a private- or public-sector savings or insurance system have major difficulties coping with unpredictable climate situations, along with life’s other contingencies. 

Extreme events like flooding and cyclones cause substantial human and material losses, as attested by the impacts of tropical cyclone Idai on Mozambique (2019) and the widespread flooding that followed on hurricane Katrina in Louisiana (2005).

In cases of flooding, inhabitants have to move out at least temporarily, but they often find refuge in surrounding areas and return home as soon as they deem it possible to do so. When a cyclone is predicted in the Gulf of Bengal, people flee to shelters constructed for that purpose, returning home as soon as the danger is over. After learning that tropical cyclone Phailin was on its way to the Indian state of Odisha in 2013, approximately 500,000 people left the area, but this did not amount to migration in the strict sense, i.e., long-term moves to relatively distant places. When residents of Búzi in Mozambique were displaced by cyclone Idai, they were rehoused less than 20km from the city, and a considerable number moved back after a few months. Those who remained in the new settlement area were likely to be young men and women seeking independence. When hurricane Katrina made landfall in New Orleans in September 2005, most of the 1.2 million people who had been displaced took refuge either elsewhere in Louisiana or in neighboring states. Some residents—relatively wealthy and with extensive social contacts—were able to anticipate the disaster and leave on their own before it struck. By the end of 2006, over half of the displaced population had returned. And nearly half of those who had not returned wished to do so but lacked the means. Inhabitants’ standard of living, extent of damage, and compensation conditions are major considerations in people’s decisions to return. For example, when flooding occurs in French cities, temporary housing is made available to their inhabitants before residents can return home. 

Persistent drought, such as that experienced in the Horn of Africa, has a quite different effect on mobility. This environmental change, though much more gradual, induces people to move greater distances, while large families who have lost the better part of their resources may give up their livestock and move to urban centers. 

The examples just cited attest to the wide variety of movements and displacements that occur, to the fact that a wide range of inhabitants (from the wealthy to the heavily disadvantaged) are involved, and to the strong likelihood that that those who can hope to restart their activities or who do not really have the means to move away in good conditions will return to the places they were displaced from. 

Migration is generally a planned solution for the wealthy and a last resort for all others, but it is important to be aware that strategies for staying in place are also continuously being developed and modified. 

While many inhabitants of the Brahmaputra River delta in Bangladesh did flee the threat of sea rise by moving to the capital city Dacca or migrating to India, others went no further than areas just outside their home base, settling on newly emerged land.

Years of drought can make living conditions in a given place increasingly difficult, particularly for farmers, but many people are not actually driven to leave. Farmers and livestock owners may try to adapt by diversifying their crops, animals, or activities. Families confronting an extreme weather event often remain in place because a member who has previously migrated to a different area or a city is now in a position to assist them. In some instances, climate events or more gradual environmental changes increase the likelihood of departure, but some studies have also shown the opposite effect: families that find themselves in temporary economic straits—a poor harvest, for example—may not have the means to leave or to help a member migrate, and may therefore prefer to postpone leaving. 

Inhabitants of lesser-developed countries living in areas heavily exposed to climate risks are tempted to reduce those risks by adapting their housing, e.g., building houses out of cement on banked land that have a better chance of coming through cyclones and flooding. In more advanced countries, we observe other ways of adapting, such as raising existing dikes higher to protect against tsunamis. Some dikes are equipped with sensors to verify the condition of buffer zones designed to receive excess storm water and so prevent damage to inhabited areas. Home state support—India in the example of shelters in the Gulf of Bengal, the Netherlands for the long-standing construction and recent reinforcement of dikes—is crucial to the development of these kinds of initiatives and infrastructure. 

Once again, it is important to realize that a substantial proportion of the forced displacements caused by climate-driven disasters are temporary and involve short distances. The numbers of such moves—short-distance and temporary—may therefore shoot up without causing a similar rise in migration. And solutions exist for coping with some of the environmental changes brought about by climate change, be they unpredictable climate-related contingencies or more gradual environmental processes. However, the development and use of such solutions implies awareness that they are possible, concerted work at the regional level, and above all, financial and other resources. This in turn means that for many populations throughout the world, particularly in the global South, the challenge posed by climate change remains immense. 

Contact : Jacques Véron, Valérie Golaz
Online: December 2016
Updated: May 2024

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