Development environment

Disasters and Climate Change

Millions are displaced from their homes every year as result of their exposure and vulnerability to a variety of hazards.

An average of 25.3 million displacements have been brought on each year since 2008 by sudden-onset disasters alone.

In 2016, 24.2 million new disaster displacements were brought on by sudden-onset natural hazards in 118 countries disaster displacements – outnumbering new displacement associated with conflict and violence by three to one.

Climate change, in tandem with poverty, inequality, urban population growth, poor land use management and weak governance, is increasing the risk of displacement and its impacts.

In sudden-onset contexts, such as when major earthquakes occur, displacement brings the disruption of normal life and livelihoods and heightened protection concerns for people with specific needs and rendered homeless such as women, children, older people and people with disabilities.  

In slow-onset contexts, displacement signals significant and increasing distress among people pushed beyond their normal coping capacities. A combination of driving factors may include drought-impacts on food insecurity, or the loss of habitable land and viable livelihoods due to desertification, erosion and sea-level rise.

Those affected include not only those who are themselves displaced, but also host families and communities with whom they take refuge, and people who remain behind in unsafe and deteriorating conditions.

The evolution of displacement depends greatly on the context in which it occurs. In some cases, people evacuated are able to return to their homes soon afterwards, while in others safe return is not an option or homes are lost and people may remain displaced for years.

Large-scale displacements may have destabilising effects on both disaster-affected and receiving areas and its complex dynamics add greatly to the challenge of ensuring vulnerable people are adequately assisted and protected.

Protracted displacement in disaster contexts is associated with some of its most profound impacts, such as cultural and community dislocation, psychosocial impacts on mental health and social well-being and loss of livelihoods, and has disproportionate impacts on vulnerable and marginalised members of society.  Knowledge and awareness of such situations, on the other hand, is weak. 

Conflicts are not the only drivers of forced displacement in the modern world. A number of global trends, such as population growth, urbanisation, poverty, food insecurity and water scarcity, together push hundreds of thousands of people to move. Climate change is the main force multiplying the impact of all these trends. Antonio Guterres UN Secretary General

Trends in exposure and vulnerability

(from Global Estimates 2015, and Global Report on Internal Displacement 2016)

The occurrence of displacement mirrors people’s exposure to hazards around the world. Exposure is increasing because ever growing numbers of vulnerable people live in areas prone to hazards.

Two key drivers of exposure and vulnerability are urban population growth in developing countries, and economic growth. The urban population in developing countries has increased by 326 per cent since 1970.

This rapid growth has for the most part been unplanned and poorly governed, leading to high exposure and vulnerability. Middle-income countries bear the brunt of the phenomenon. People in low-income countries are more vulnerable still, but relatively fewer people are exposed to hazards. That said, population projections suggest that exposure will increase in many low-income countries over the coming decades.

Relative to population size, small island states face disproportionately high disaster-related displacement risk. Their mostly low-lying coastal populations tend to be exposed to a range of hazards, particularly cyclones, floods, landslides, earthquakes and tsunamis.

The generally low vulnerability of high-income countries does not mean that they are not affected. This is explained by three factors: All countries are vulnerable to the most extreme hazards; inequality within high-income countries makes displacement a particular concern for relatively poorer people and those subject to discrimination and marginalisation; and effective early warning systems and disaster responses save lives, but increase displacement among survivors.

Our work