Minister's Column

Climate Change and Forced Migration


In February 2010 the US Defense Department reported that “climate-related changes are already being observed in every region of the world” and “will contribute to food and  water scarcity, will increase the spread of disease, and may spur or exacerbate mass migration.” The United Nations Office of Coordination of Humanitarian Affairs estimates that in 2008 “climate-related catastrophes” drove more than 20 million people from their homes. A study by scientists at Columbia University suggests that, if present trends continue unchecked until mid-century, the figure could rise to 200 million or higher.

Climate changes resulting from global warming can have disastrous effects on the livelihood of people in the developing world: 

            -Changes in seasonality of river flow, resulting from glacier shrinkage and diminished winter snowpack, threaten agricultural systems in Asia on which almost one quarter of the world’s inhabitants depend.

            -Disruptions of rainfall patterns resulting from rising temperatures are projected to produce more prolonged dry spells, punctuated by fewer but more intense downpours, a pattern already being observed in Southeast Asia, Mexico and Central America, and sub-Saharan Africa. Agricultural lands in the developing world are currently being lost both to desertification, resulting from droughts, and to increased frequency and severity of flooding.

            -Dangers from rising sea levels are not limited to small island nations. In India alone, a rise of one meter would displace more than 40 million people.

Some of these effects could be reduced by adaptive measures, e.g. promoting more climate-resilient agricultural practices, but the developing countries most directly threatened also have the fewest resources to support adaptation.

Preventing a major humanitarian disaster will require a serious reduction in greenhouse gas emissions through mitigation. 

For more information:

DeSherbinin et al., “Casualties of Climate Change,” Scientific American January 2011, Vol. 304 No.1,

Warner et al., “In Search of Shelter: Mapping the Effects of Climate Change on Human Migration and Displacement,” 

U.S. Department of Defense, 2010 Quadrennial Defense Review, 

European Commission, Environmental Change and Forced Migration Scenarios Project, 

CARE International Climate Change Information


Picture at top is Net migration rates for 2008: positive (blue), negative (orange), stable (green), and no data (gray) (Wikipedia)

*Article written by Guy Quinlan, UU-UNO Climate Advisory Group



Dash, J. (2011). Climate Change and Forced Migration. Retrieved from


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