Environment a Growing Driver in Displacement of People

The number of people who are on the move involuntarily worldwide may be as high as 184 million—roughly equivalent to the entire population of Brazil, or one out of every 36 persons on Earth.¹ Among them are 16 million refugees (including 4.6 million Palestinians) and 26 million internally dis­placed people (IDPs—those who, unlike refugees, did not cross an international border).² (See Figures 1 and 2.) Another 12 million people are stateless—they are vulnerable because they lack the protection of citizenship, although they are not necessarily displaced.³ Some 25 million people have been uprooted by natural disasters.⁴ And Christian Aid, a London-based advocacy group, estimates that as many as 105 million people are made homeless by a variety of so-called development projects, including dams, mines, roads, factories, plantations, and wild­life reserves.⁵

Because these estimates come from different sources, the total of 184 million needs to be regarded with some caution. This is especially so because the Christian Aid figure is a rough estimate and may partially overlap with the other categories.

Environmental and resource pressures are increasingly a driver of displacement. They also have an impact on the number of long-term migrants—people who leave voluntarily and live outside their home country for a year or longer—whose numbers rose from 75 million in 1965 to some 200 million in 2005.⁶ In relative terms, however, the number of long-term migrants has remained at roughly 2–3 percent of global population.⁷