The phenomenon is well known since long, but concrete numbers are rare: more and more people are forced to relocate permanently from their homes, due to environmental degradation and ecosystem losses.
Projections for 2050, released by the International Organization of Migration in 2008, range from 25 million to one billion people displaced by the consequences only of climate change. Their livelihoods are threatened in many ways: farmers lose arable land due to droughts and other extreme weather events whereas islands and coastal areas are affected by devastating storm tides. As a result, people migrate from environments which no longer guarantee food stability and which no longer are hospitable for human civilization.