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 (UNHCR) 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.Dai, Aiguo. “Drought Under Global Warming: a Review.” Wiley interdisciplinary reviews. Climate change 2, no. 1 (2011): 45–65.Hansen, James, Makiko Sato, Paul Hearty, Reto Ruedy, Maxwell Kelley, Valerie Masson-Delmotte, Gary Russell, et al. “Ice Melt, Sea Level Rise and Superstorms: Evidence from Paleoclimate Data, Climate Modeling, and Modern Observations That 2 °c Global Warming Could Be Dangerous.” Atmospheric chemistry and physics 16, no. 6 (2016): 3761–3812.
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."The Impact of Natural Disasters". Sciencing. Retrieved 24 November 2021. 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.Cissé, G., R. McLeman, H. Adams, P. Aldunce, K. Bowen, D. Campbell-Lendrum, S. Clayton, K.L. Ebi, J. Hess, C. Huang, Q. Liu, G. McGregor, J. Semenza, and M.C. Tirado, 2022: Health, Wellbeing, and the Changing Structure of Communities. In: Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 1041–1170,
Rising sea levels are a frequently addressed concern in environmental discussions. Sea levels are estimated to rise between 90 and 180 centimeters (roughly 3 and 6 feet) 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.Rajkovich, Nicholas B., and Seth H. Holmes, eds. Climate Adaptation and Resilience Across Scales : from Buildings to Cities / Edited by Nicholas B. Rajkovich and Seth H. Holmes. New York, NY: Taylor & Francis, 2022. 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.Smit, Barry, and Olga Pilifosova. "Adaptation to climate change in the context of sustainable development and equity." Sustainable Development 8, no. 9 (2003): 9. 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.Zickgraf C. and N. Perrin. 2016. Immobile and Trapped Populations. The Atlas of Environmental 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'.Warner K and Laczko F. (2008). ‘Migration, Environment and Development: New Directions for Research ’, in Chamie J, Dall’Oglio L (eds.), International Migration and Development, Continuing the Dialogue: Legal and Policy Perspectives, IOM, page 235
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,Stern, N. (Ed.) (2006). The Economics of Climate Change: The Stern Review, Cambridge University Press, Cambridge as well as by NGOs such as Friends of the Earth,Friends of the Earth, 'A Citizen's Guide to Climate Refugees, Fact Sheet Four: Predictions of Climate Refugees to 2050' (FOTE: London), 2007: 10 Greenpeace Germany (Jakobeit and Methmann 2007)Jakobeit, C., and Methmann, C. (2007). Klimafluchtlinge – Die Verleugnete Katastrophe, Greenpeace, Hamburg and Christian Aid;Christian Aid (2007). ‘Human Tide: The Real Migration Crisis ’ (CA: London), page 6 and inter-governmental organisations such as the Council of Europe,Parliamentary Assembly Doc. 11084, 23 October 2006, The Problem of Environmental Refugees: 1 UNESCO, and UNHCR.UNHCR (2002), ‘A critical time for the environment’, Refugees No.127. Geneva. 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.