Population migration refers to the movement of people from one place to another. It usually implies that many individuals are leaving a particular area and relocating to a different region or country. Full definition
Lower yields of crops or damage to crops, water stress, food insecurity, malnutrition, poor health and increased risk of population migration are forecast to become more common globally. (www2.unccd.int)
The federal disaster area spanned the size of Great Britain, at least 1,836 people perished and some 1.5 million people were displaced, creating the largest population migration in the U.S. since the dust bowl of the 1930s. (scientificamerican.com)
Disruption by flood and high winds; withdrawal of risk coverage in vulnerable areas by private insurers, potential for population migrations, loss of property (ipcc.ch)