The displacement of human populations refers to the relocation of large numbers of people from their homes. On this website, we focus on human displacement driven directly or indirectly by non-human or human-caused changes in the physical environment, which create shortages of essential resources. For example, climate change can reduce regional precipitation and convert farmland into desert. Unfortunately, the displacement of human populations is not only caused by environmental changes, but often occurs because of inequitable social and political systems that do not provide people with protection, food, clean water, and healthcare.
Either sudden or long-term changes in Earth’s environment can force or motivate people to leave their homes to preserve their health and well-being. These changes are caused by a variety of factors related to human use of Earth’s resources, climate change, and non-human processes. Some of the reasons for the displacement of human populations include:
Residents walk on a road littered with debris after Super Typhoon Haiyan battered Tacloban city in central Philippines November 10, 2013. Credit: Daria Devyatkina
- Decreases in the availability of freshwater for both drinking and agriculture.
- Decreases in quality, availability, and nutritional value of food.
- Extreme weather events, including droughts when precipitation decreases, and hurricanes that bring high winds and flooding.
- Flooding due to sea level rise.
- Habitat loss from activities such as deforestation.
- Earthquakes, volcanic eruptions, or fires that alter landscapes.
Can you think of additional cause and effect relationships between the displacement of human populations and other parts of the Earth system?
Visit the freshwater quality and availability, food availability and nutrition, and health and diseases pages to explore more connections between the displacement of human populations and global changes.