Climate change and forced migration: Observations, projections and implications

The document examines the complex relationship between anthropogenic climate change and forced migration, arguing that while precise numerical predictions (such as 200 million migrants by 2050) are tentative, the 'carrying capacity' of many regions will be compromised. It distinguishes between slow-onset climate processes and sudden climate events, noting that non-climate drivers like governance and poverty are equally critical. The author outlines three scenarios—'The Good', 'The Bad', and 'The Ugly'—based on IPCC emission storylines, and highlights that the poorest countries will bear the heaviest burden of displacement. The paper concludes that forced climate migrants currently 'fall through the cracks' of international law and national adaptation strategies, which often view migration as a failure of adaptation rather than a tool for it.

• Predicting the exact number of future climate migrants is highly complex and uncertain due to a lack of baseline data, the influence of population growth, and the unpredictability of climate evolution. The widely cited figure of 200 million forced climate migrants by 2050 is described as a 'tentative' prediction based on 'heroic extrapolations'.
• Climate-driven migration is caused by two distinct meteorological drivers: slow-onset 'climate processes' (such as sea-level rise, desertification, and salinisation) and sudden 'climate events' (such as storms, hurricanes, and glacial lake outburst floods).
• Non-climatic factors, including government policy, population growth, and a community's adaptive capacity, are as critical as climate signals in determining vulnerability. A natural hazard only becomes a 'disaster' when a community lacks the resources or planning to weather the event.
• The ability to migrate is not universal but is a function of a household's social and financial capital. The most vulnerable people may be unable to migrate, while those with more resources are more likely to move, often following pre-existing cultural or colonial paths.
• Forced migration negatively impacts development in four primary ways: by straining urban infrastructure, undermining economic growth through 'brain drain', increasing the risk of ethnic and political conflict, and worsening health and education outcomes for migrants.
• There is a significant gap in international law regarding the status of climate-displaced people. They do not fit the 1951 Convention's definition of a 'refugee' (which requires political persecution), and there is strong resistance among developed nations to expand this definition due to the legal obligations it would entail.
• National Adaptation Programmes of Action (NAPA) in least developed countries generally fail to incorporate migration as a policy response, typically viewing it as a 'failure of adaptation' rather than a legitimate adaptive strategy.

APA

Brown, O. (2007). Climate change and forced migration: Observations, projections and implications. International Institute for Sustainable Development. https://www.iisd.org/system/files/publications/climate_forced_migration.pdf

Chicago

Brown, Oli. Climate change and forced migration: Observations, projections and implications. International Institute for Sustainable Development, 2007. https://www.iisd.org/system/files/publications/climate_forced_migration.pdf.

Wikipedia

{{cite report |last1=Brown |first1=Oli |title=Climate change and forced migration: Observations, projections and implications |publisher=International Institute for Sustainable Development |date=2007 |url=https://www.iisd.org/system/files/publications/climate_forced_migration.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{brown2007climate, author = {Brown, Oli}, title = {{Climate change and forced migration: Observations, projections and implications}}, institution = {International Institute for Sustainable Development}, year = {2007}, url = {https://www.iisd.org/system/files/publications/climate_forced_migration.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }