Disaster

Exportation

Deterioration

An unintended, catastrophic event triggers human migration

The willful destruction of the environment renders it unfit for human habitation

An incremental deterioration of the environment compels migration as constraints to human survival increase

Sub-Category

Natural

Technological

Development

Ecocide

Pollution

Depletion

Origin

Natural

Anthropogenic

Anthropogenic

Anthropogenic

Anthropogenic

Anthropogenic

Intention of Migration

Unintentional

Unintentional

Intentional

Intentional

Unintentional

Unintentional

Duration

Acute

Acute

Acute

Acute

Gradual

Gradual

General Example

Volcano

Meltdown

Dam Building

Defoliation

Global Warming

Deforestation

Real-World Example

Montserrat

US-TMI

China – 3G

Vietnam

Bangladesh

Ecuador-Amazon

Estimated Number Displaced

7000

144,000

1.3 million

7 Million*

15 million

115,000