The number of people forcibly displaced within their own countries by so-called natural disasters and extreme weather events rose sharply in 2025, according to a study conducted by the University of Hamburg on behalf of environmental organization Greenpeace.
The report found that 13.6 million people were internally displaced by disasters last year, up from 9.9 million in 2024.
The figures are based on data from the Internal Displacement Monitoring Centre (IDMC). Released on Friday, the study argues that climate change is increasing both the frequency and severity of extreme weather events, with countries in the Global South bearing a disproportionate share of the impact.
It also notes that armed conflicts and violence—another major driver of internal displacement—have reached their highest levels since World War II.
At the same time, global funding for humanitarian aid and development cooperation fell by roughly one quarter in 2025, a reduction of approximately $175 billion compared with the previous year.
Against this backdrop, an estimated 82.2 million people worldwide were living away from their homes last year, down slightly from 83.5 million in 2024.
The report highlights Afghanistan as a striking example of the overlapping pressures driving displacement. Melting Himalayan glaciers are threatening the country’s supplies of drinking and irrigation water, while prolonged droughts followed by sudden and severe flooding have repeatedly forced communities to leave their homes.
According to the study, Kabul could become the first major city in the world to run out of potable water in the near future, echoing warnings previously issued by other non-governmental organizations.
