Climate migration
Climate migration is a subset of climate-related mobility that refers to movement driven by the impact of sudden or gradual climate-exacerbated disasters, such as "abnormally heavy rainfalls, prolonged droughts, desertification, environmental degradation, or sea-level rise and cyclones". Gradual shifts in the environment tend to impact more people than sudden disasters. The majority of climate migrants move internally within their own countries, though a smaller number of climate-displaced people also move across national borders.
Climate change gives rise to migration on a large, global scale. The United Nations High Commissioner for Refugees estimates that an average of 20 million people are forcibly displaced to other areas in countries all over the world by weather-related events every year. Climate-related disasters disproportionately affect marginalized populations, who are often facing other structural challenges in climate-vulnerable regions and countries. The 2021 White House Report on the Impact of Climate Change on Migration underscored the multifaceted impacts of climate change and climate-related migration, ranging from destabilizing vulnerable and marginalized communities, exacerbating resource scarcity, to igniting political tension.
Few existing international frameworks and regional and domestic legal regimes provide adequate protection to climate migrants. However, as the UN Dispatch noted, "people who have been uprooted because of climate change exist all over the world — even if the international community has been slow to recognize them as such." As a result, climate migration has been described as "the world's silent crisis", contrasting its global pervasiveness with its lack of recognition and investigation. Estimates on climate-related displacement vary, but all point to an alarming trend. Some projections estimate that around 200 million people will be displaced by climate-related disasters by 2050. Some even estimate up to 1 billion migrants by 2050, but these take ecological threats, including conflict and civil unrest as well as disasters, into account.
Causes
Climate migrants refer to those who engage in movement driven by the impact of sudden or gradual climate change, such as "abnormally heavy rainfalls, prolonged droughts, desertification, environmental degradation, or sea-level rise and cyclones". The intensification of natural disasters caused by climate change, has the potential to impact many populations, leading to a significant number of climate migrants. Over the past 50 years, the frequency of disasters has increased by a factor of 5. In addition to more frequent and severe disasters, global warming-induced rising temperatures will lead to more prevalent droughts and snow and ice melting, resulting in higher sea levels.Gradual shifts in the environment tend to impact more people than sudden disasters. Between 1979 and 2008, storms impacted 718 million individuals, whereas droughts affected approximately 1.6 billion. Sudden climatic events like severe storms and natural disasters may destroy critical infrastructure, flood neighborhoods, disrupt transit systems, overburden medical centers, cause food and water shortages, destabilize energy plants, and jeopardize human health and well-being. These events can severely harm communities, making recovery a challenging process. Gradual impacts, such as famines, droughts, and other resource shortages and economic damages brought about by climate change may cause conflict, political instability, climate gentrification, and accumulated negative health effects due to exposure to unhealthy environments. Droughts and slowly rising temperatures, have more mixed effects, but are more likely to lead to longer-term changes.
Rising sea levels are a frequently addressed concern in environmental discussions. Sea levels are estimated to rise between 90 and 180 centimeters by 2100. This means that, progressively, land areas will become submerged. To put it in perspective, on average each year, the sea level has risen 3.7 mm. These data reveal significant threats to coastal cities and ecosystems, potentially displacing many humans.
Climate justice and adaptation
There are several ways of looking at migration and environmental change. Migration can be a human rights issue or a security issue. The human rights framing suggests developing protection frameworks for migrants. Increased border security may be an implication of treating migration as a national security issue. It is possible to combine both approaches, taking national concerns into account in accordance with human rights.Climate adaptation projects in preparation for climate hazards and as a response to climate change may increase the climate resilience of communities. However, these projects may inadvertently contribute to climate gentrification—a process where actions to address climate risks lead to the displacement of lower-socioeconomic groups by wealthier communities. Inner coastal cities and areas at higher elevations, traditionally occupied by less affluent populations, are now becoming more desirable due to increasing risks like sea level rise and extreme weather events affecting lower-lying wealthy waterfront properties.
By bolstering resilience, such projects may reduce the degree of migration people feel compelled to undertake due to climate-related challenges. Varying levels of investment are made in supporting the adaptation, resilience, and mobility of neighborhoods, municipalities, and nations in the face of climate change and consequent environmental migration. This is especially important to consider since small island states, rural populations, people of color, low-income communities, the elderly, people with disabilities, coastal urban populations, food and housing insecure households, and developing countries are especially vulnerable to the worst effects of the climate crisis and therefore to environmental migration. Just as individuals and countries do not contribute equally to climate change, they also do not experience the negative effects of the crisis equally. Both short- and long-term impacts of climate change bring under-prepared communities environmental harm and exacerbate existing inequities. People with livelihoods tied to the environment, like those in agriculture, fisheries, and coast-dependent businesses, are also at risk of relocation or job loss due to climate change. If communities cannot adapt adequately, migration might emerge as the primary response.
Climate migrants may migrate internally within their own country or to another country in response to climate change. Most climate migration is internal, meaning movement occurs within an individual's own country, and they do not cross international borders. In 2022 alone, weather-related events led to nearly 32 million internal displacements. In poor countries where individuals are more vulnerable to disasters due to inadequate climate adaptation, individuals will also often lack resources for long-distance migration.
In some cases, climate change constrains migration and people may lose the means to migrate, leading to a net decrease in migration. The migration that does take place is seen as voluntary and economically motivated. In some cases climate change could also exacerbate economic insecurity or political instability as causes for migration beyond temperatures and extreme weather events. Who moves and who stays when affected by climate change often falls along lines of race and class, as mobility requires some amount of wealth.
Global statistics
In 1990, the Intergovernmental Panel on Climate Change declared that the greatest single consequence of climate change could be migration, 'with millions of people displaced by shoreline erosion, coastal flooding and severe drought'.The most common projection is that the world will have 150–200 million people displaced by climate change by 2050. Variations of this claim have been made in influential reports on climate change by the IPCC and the Stern Review on the Economics of Climate Change, as well as by NGOs such as Friends of the Earth, Greenpeace Germany and Christian Aid; and inter-governmental organisations such as the Council of Europe, UNESCO, and UNHCR. There has even been an estimate as high as 1.2 billion attributing climate migration to ecological threats, including conflict and civil unrest. This acknowledges that such ecological challenges might instigate conflicts, such as regions disputing over water access. Other reports with more conservative estimates focus solely on the direct effects of climate.
Predictions on climate-induced migration often reflect the population in at-risk regions rather than the actual expected number of migrants, and not considering adaptation strategies or varying levels of vulnerability. However, Hein de Haas has argued that to link the climate change issue "with the specter of mass migration is a dangerous practice based on myth rather than fact. The use of apocalyptic migration forecasts to support the case for urgent action on climate change is not only intellectually dishonest, but also puts the credibility of those using this argument - as well as the broader case for climate change action - seriously at risk". He argued that while "climate change is unlikely to cause mass migration" this also overlooks the fact that the implications of environmental adversity are most severe for the most vulnerable populations who lack the means to move out.
According to the United Nations High Commissioner for Refugees, by the end of 2023, over 117 million people worldwide were forcibly displaced, with 68.3 million remaining internally displaced within their own countries. A significant proportion of these displacements are linked to environmental and climate-related factors. The Internal Displacement Monitoring Centre reported that 7.7 million people were living in internal displacement specifically due to disasters in 2023, highlighting the growing role of climate-related events in driving migration.
Furthermore, the IDMC's 2024 Global Report on Internal Displacement highlights that, as of the end of 2023, 7.7 million people across 82 countries and territories were living in internal displacement specifically due to disasters, including those related to climate change.
While climate-related migration is often framed as a remote issue, extreme weather events are already forcing people out of their homes in many parts of the world. In 2021, storms, floods, landslides, wildfires and droughts triggered 23,7 million internal displacements, according to the Internal Displacement Monitoring Centre. This makes up for 60% of all internal displacements that year.