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".[1] Gradual shifts in the environment tend to impact more people than sudden disasters.[2] The majority of climate migrants move internally within their own countries, though a smaller number of climate-displaced people also move across national borders.[3]
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.[4] Climate-related disasters disproportionately affect marginalized populations, who are often facing other structural challenges in climate-vulnerable regions and countries.[4] As a result, climate-related disasters are often described as a threat multiplier that compounds crises over time and space. 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.[5]
Few existing international frameworks and regional and domestic legal regimes provide adequate protection to climate migrants.[4] 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."[6] 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.[7] Estimates on climate-related displacement vary, but all point to an alarming trend. The most common projections estimate around 200 million people will be displaced by climate-related disasters by 2050.[8][9] 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.[10][11]